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In this study, rare earth (RE) Ce is used to modify the interaction between atoms in 7CrSiMnMoV die steel castings. The tensile properties are performed, and strengthening mechanism are analyzed by investigated fracture surface, and microstructure by optical microscopy (OM) and scanning electron microscope‐energy dispersive spectrometer (SEM‐EDS). And ab initio molecular dynamics (AIMD) is used to simulate the effect of the Ce element on the local atomic structure of the FeCeC system alloy steel. The results indicate the strength can increase from 722.55 to 1074.27 MPa, and the elongation can increase from 24.86% to 44.22% with a RE Ce concentration of 0.009%. It is attributed to that doping of Ce can inhibit the formation of network eutectic cementite, refine the lamellar spacing of pearlite, and even form granular cementite and martensite structures. AIMD simulation results show that C atoms tend to be surrounded by Fe, and the strong chemical bonds of FeC make the Fe‐centered C more stable with an increase in RE Ce concentration. And doping Ce can introduce new local topological and chemical orderings such that the FeCFe triplets predominantly form small and big angles shifting from near 75° and 136° to 47° and 81°, respectively. [ABSTRACT FROM AUTHOR]

The electrification of automotive is growing rapidly, resulting in an increased need for aluminum alloys with high electrical conductivity. The core element of the electric vehicle, besides the batteries, is an electric motor, which replaces the internal combustion engines of a traditional gasoline vehicle. These applications require both high strength and high electrical conductivity. This paper presents the development of a new Al-Fe-Ni aluminum alloy that provides a good combination of mechanical properties and electrical conductivity. The alloy is well suited for high-pressure vacuum die casting (HPVDC). The as-cast microstructures, mechanical properties and electrical conductivity were studied for alloys with different Fe/Ni combination. The relationship between the microstructure and properties is analyzed, and the strengthening mechanisms of the studied alloy are discussed. Based on the experimental results, the new alloy demonstrates excellent potential for electric vehicle applications produced by high-pressure vacuum die casting. [ABSTRACT FROM AUTHOR]

Alloy wheels must meet rigorous durability and safety tests to meet structural demand during use. The use of aluminum (Al) alloyed with silicon (Si) stands out due to the good relationship between density and strength and also its esthetic appeal, which is made possible by the suitable alloy machinability. The use of A356 alloy processed through low-pressure die casting and T6 heat treatment comes from the need for suitable mechanical properties and ease of large-scale cyclic processing. The wheel sector's high competitiveness demands accelerated development with less time-to-market and better performance. The use of numerical cast simulations helps predict the thermal and microstructural parameters of the alloy resulting from the solidification process inside a metallic mold. Understanding the solidification thermal parameters is of great importance for predicting either the phase morphologies or the dendritic length-scale of the casting, since these features have a direct impact on the alloy's strength. The present study aims to develop a computational simulation tool using commercial casting software to predict the tensile properties of as-cast and heat-treated automotive wheels. To achieve this objective, directional solidification (DS) experiments with the A356 alloy were carried out in order to determine equations relating the solidification time and cooling rate along the casting. The generated casting by the DS was further divided into parts, heat-treated and untreated, and each half part was examined for both tensile testing and the determination of secondary dendrite arm spacing (λ2). This allowed the development of key experimental equations relating λ2 with solidification time and tensile properties with λ2. In the end, a coupled simulation tool underwent testing using real tensile test data from wheels before and after T6 treatment. This testing involved two methods of correlating tensile properties with λ2: Hall-Petch-type (HP) and Ludvig model approaches. The HP model more accurately represents the strength data from various wheel regions, with a small average error of approximately 5.6% for ultimate strength. [ABSTRACT FROM AUTHOR]

In this study, the vacuum-assisted high-pressure die casting (VHPDC) process was used to produce 3-mm thin-walled AlSi9Cu3 alloy. The thermal and mechanical properties of the material were investigated using differential scanning calorimetry (DSC), a universal testing machine, a laser flash analyzer (LFA), and a thermal mechanical analyzer (TMA). A preliminary determination of the aging and solution temperature range was conducted via DSC. The thermal expansion of the as-cast (F) samples after heating to 480 °C for 6 h was measured using TMA, and further verified after heat treatment of the solution at 480 °C for 30 min through tensile testing. The thermal expansion dimension and thermal conductivity changes from 25 to 300 °C in the as-cast (F), T5, and T6 states were measured via TMA and LFA. The heat treatment process parameters of thin-walled die castings could be determined by combining the thermal analysis (DSC and TMA) and mechanical tensile test results. Furthermore, the heat treatment at 200 °C for 4 h and 480 °C for 30 min combined with 200 °C for 4 h achieved improved mechanical properties (tensile strength Rm ≥ 320 MPa), good dimensional stability and the thermal conductivity at 150 °C was higher than 150 W/(m °C). [ABSTRACT FROM AUTHOR]

The effects on phase equilibria of La and Fe additions to the Al–Ce–Ni-based alloy system are explored under high-pressure die casting conditions. The addition of La to Al–Ce–Ni-based alloy system only reacts with Ce synergistically to promote the formation of the Al11(Ce,La)3 intermetallic phase as predicted by CALculation of PHAse Diagrams (CALPHAD) and verified experimentally. High Fe additions react with Ni to form the Al9FeNi intermetallic phase, which is an additional eutectic former. The targeted co-precipitation type eutectic morphology is achieved in the alloys studied. Additional coarse particles of Al11(Ce,La)3, present in the alloys studied and not predicted by CALPHAD, are attributed to possible inclusions of Ce and La oxide, present in the mischmetal feedstock used. Both alloys exhibit exceptional mechanical stability after 10 hours at 400 °C due to the stability of the phases formed during solidification. The alloy with high Fe additions possessed better mechanical properties after heat treatment based on the higher eutectic content and more substantial improvement to the morphology of secondary phases after treatment. [ABSTRACT FROM AUTHOR]

The present study investigates the structure-property relationship of gravity die-cast and rheocast in situ processed 1wt%TiB2/Al-3.5Mg-0.15Sc-0.075Zr composites. The reinforcement was synthesized via the reaction of fluoride salts (K2TiF6 and KBF4) in the melt at 750 °C for an hour. The cooling slope technique was used for rheocasting, wherein the melt (pouring temperature of 700 °C) was allowed to flow over the cooling slope at an angle of 60°. Thereafter, all samples (gravity die cast and rheocast) were aged at 300 °C for 5 h. Microstructural characterization, hardness measurements, tensile tests, and fractography were necessary supplements to this investigation. The results obtained from this investigation infer: (a) The presence of nano-TiB2 particles increases the ductility (15%) of the gravity die-cast specimens; (b) rheocasting increases the strength of the specimen due to transformation from dendritic to equiaxed dendritic morphology and uniform particle distribution (reduced agglomeration). (c) Rheocast and aged specimens show maximum strength and adequate ductility due to the combined effects of structure refinement, reduced agglomeration, and the formation of fine precipitates. [ABSTRACT FROM AUTHOR]

In the high-pressure die casting method (HPDC), the determination of the cast-mold interface heat transfer coefficient (IHTC) is important for improving the part quality. This value varies depending on the casting temperature, mold temperature, injection pressure, injection velocity, mold design and various parameters. In this study, the IHTC and heat flux values during high-pressure die casting were determined using A384 alloy. In this direction, time-dependent temperature data were experimentally recorded with 18 thermocouples positioned on the mold and casting part, and the IHTC and heat flux were calculated with the program using the finite difference method. Studies were repeated depending on different injection pressure (80, 160 bar), injection velocity (1.5, 2.5 m/s), mold temperature (373, 453, 533 K) and casting temperature (973, 1033 K) parameters. In addition to experimental studies, ANSYS Fluent was used to simulate the HPDC process. Thus, simulations were carried out using the same parameters as in the experimental studies, and the results of the IHTC and heat flux values were determined. As a result of the studies, it was observed that increasing the injection pressure, injection second phase velocity, and casting temperature led to an increase in both the IHTC value and the heat flux. On the other hand, increasing the mold temperature had an inverse effect on these values and caused them to decrease. In addition to the aforementioned process parameters, it was shown through experimental studies that the IHTC and heat flux values increased when vacuum application was used. [ABSTRACT FROM AUTHOR]

The microstructure and mechanical properties of Mg–5Zn–2Gd–0.6Zr under different processes (permanent mold casting, semi-solid metal (SSM) die casting, and T6 heat treatment after SSM die casting) were investigated using SEM, XRD and tensile mechanical tests. The results demonstrated that Mg–5Zn–2Gd–0.6Zr alloy was composed of α-Mg, quasicrystal I phase (Mg3Zn6Gd) and W phase (Mg3Zn3Gd2). Compared to permanent casting specimens, the microstructure and mechanical properties of Mg–5Zn–2Gd–0.6Zr alloy could be significantly improved by the SSM die casting process, where non-dendrite and spheroidal crystal structures were formed. After SSM die casting, the second phase exhibited a continuous reticular morphology and precipitated along the grain boundaries. The average grain size was 56.4 μm with a shape factor of 0.81. As a result, the mechanical properties were remarkably reinforced, with a tensile strength of 233 MPa and an elongation rate of 9.8%. After T6 heat treatment, the second phase changed from continuous network morphology to fine particle-like dispersed distribution around the grain boundaries. Due to the improved microstructure, the mechanical properties were further enhanced, with a tensile strength of 277 MPa and an elongation rate of 7.1%. [ABSTRACT FROM AUTHOR]

High-pressure die casting (HPDC) is a permanent mold-based production technology that facilitates the casting of near net shape components from nonferrous alloys. The pressure and temperature conditions within the cavity impact the cast product quality during and after the conclusion of the die filling process. Die surface cavity sensors can deliver information describing the conditions at the die-casting interface. They are associated with high costs and limited service lifetimes below the achievable total cycle count of the die inserts and therefore ill-suited for industrial use cases. In this work, the suitability of long short-term memory (LSTM) recurrent neural networks (RNN) for substituting physical cavity temperature and pressure sensors virtually after the production ramp-up or at the end of the sensor service life is investigated. Training LSTMs with data of 233 casting cycles with different process parameters provides networks which are then applied to 99 further cycles. The prediction accuracy is investigated for different time interval lengths in the solidification and cooling phase. For longer time intervals, the cavity pressure prediction deteriorates, potentially due to a highly individual and hardly ascertainable buildup of casting distortion and internal stresses. Overall, however, the accuracy of the developed LSTMs is excellent for the cavity temperatures and good for the cavity pressures. [ABSTRACT FROM AUTHOR]

Traditional statistical models present limitations in capturing the complexity of advanced manufacturing processes. To address this challenge, the integration of the iteratively weighted least squares (IWLS) method in the training of a backpropagation neural network (BPNN) model is proposed. This combination allows for the application of generalized linear model (GLM) statistical inference, forming a hybrid learning approach that enhances both predictive accuracy and model interpretability. The hybrid approach provides robust statistical support, identifying critical factors in manufacturing processes and offering a comprehensive tool for model evaluation and an in-depth understanding of process dynamics. The applicability of the method is demonstrated through the analysis of two manufacturing processes and identifying their key factors. The results of the deviance analysis and hypothesis testing highlight metal temperature and solidification time as crucial factors in the die casting process and input voltage as a crucial factor in the TIG welding process. This method underscores its practical value by improving efficiency and competitiveness in the manufacturing industry, providing detailed and accurate evaluations of process factors. [ABSTRACT FROM AUTHOR]

In order to effectively reduce energy consumption and increase range mile, new energy vehicles represented by Tesla have greatly aroused the application of integrated magnesium (Mg) alloy die casting technology in automobiles. Previously, the application of Mg alloys in automobiles, especially in automotive cockpit components, is quite extensive, while it has almost disappeared for a period of time due to its relatively high cost, causing a certain degree of information loss in the application technology of Mg alloy parts in automobiles. The rapid development of automotive technology has led to a higher requirement for the automotive components compared with those traditional one. Therefore, whatever the components themselves, or the Mg alloy materials and die casting process have to face an increasing challenge, needing to be upgraded. In addition, owing to its high integration characteristics, the application of Mg alloy die casting technology in large-sized and thin-walled automotive parts has inherent advantages and needs to be expanded urgently. Indeed, it necessitates exploring advance Mg alloys and new product structures and optimizing die casting processes. This article summarizes and analyzes the development status of thin-walled and large-sized die casting Mg alloy parts in passenger car cockpit and corresponding material selection methods, die casting processes as well as mold design techniques. Furthermore, this work will aid researchers in establishing a comprehensive understanding of the manufacture of thin-walled and large-sized die casting Mg alloy parts in automobile cockpit. It will also assist them in developing new Mg alloys with improved comprehensive performance and new processes to meet the high requirements for die casting automotive components. [ABSTRACT FROM AUTHOR]

The growth of the automotive industry and increased efforts to reduce the environmental impact of transportation require the use of more and more aluminium components in the production of new cars. The process of high-pressure die casting of aluminium makes it possible to meet the goals, but it requires the use of coolants based on oil and wax emulsions that are difficult to dispose of. A method for demulsification of real wastewater samples from the high pressure die casting process was developed and evaluated. The optimal parameters for conducting the separation process were determined, and the changes occurring in the emulsion being separated were analysed. [ABSTRACT FROM AUTHOR]

The EN AB-46000 alloy castings are widely used in automotive industry due to their relative good strength combined with a low density and an excellent conductivity. Porosity of EN AB-46000 alloys is one of the most important defects, responsible for the low strength and poor plastic properties of castings as well as their tightness. Quantitative porosity measurement were performed using quantitative metallography and image analysis methods using ImageJ. The study shows that such parameters of high-pressure die casting are the piston speed in the second casting phase and the final pressure increase in the pressing phase. It has been shown that the appropriate selection of these parameters can significantly reduce the porosity of castings made of alloy EN AB-46000. [ABSTRACT FROM AUTHOR]

In this work, we intended to study the effect of heat treatments (T5 and flash T6) on blistering, mechanical properties and microstructure for different parts produced by vacuum-assisted HPDC. These parts were produced with primary and secondary aluminium alloys (AlSi10MnMg alloy and AlSi10Mg(Fe) alloy, respectively). The parts presented blisters for all combinations of temperature (between 360 °C and 520 °C) and stage times (15 and 30 min) of solution heat treatments. However, when subjected to the T5 heat treatment, blisters were no longer visible. With this heat treatment, there was an increase in yield strength of 64% for both aluminium alloys and an increase in UTS of 31% in AlSi10Mg(Fe) alloy and of 24% in AlSi10MnMg alloy, when compared to the mechanical properties in the as-cast state. However, there was a decrease in ductility. The AlSi10Mg(Fe) alloy presented a lot of contaminations (especially iron), which impaired the mechanical properties compared to the primary aluminium alloy, AlSi10MnMg. [ABSTRACT FROM AUTHOR]

This study systematically analyzed the effect of design conditions on filling behavior and product characteristics when forming thin plates of magnesium alloy (AZ91D) of 0.5 mm or less using the die casting method. As a research method, a casting analysis simulation program was used to predict filling and solidification behavior under various process conditions. The molten metal injection temperature (610~670 °C), mold temperature (160~220 °C), and cooling water temperature (10~55 °C) were selected as key variables, and an analysis was performed for a total of five conditions. A simulation was conducted to analyze the charging speed distribution, location of oxides and bubbles, and solidification pattern. As a result of the study, the flow of molten metal in the low and high-speed sections of the plunger, uniformity of product thickness, and supply conditions of the molten metal were confirmed to be major factors. It is important to manage the molten metal injection temperature at an appropriate level to minimize product defects. Based on these conditions, a prototype was manufactured, the microstructure was observed, and a fine and uniform grain structure was observed in most areas. In mechanical property evaluation, superior physical properties were secured compared to existing bulk materials. [ABSTRACT FROM AUTHOR]

Against the backdrop of climate policy goals and the EU's aim for a resource-efficient economy, the foundry industry must rethink product range, energy consumption, and production technologies. Light metal casting, which is performed through processes like gravity die casting and high-pressure die casting, requires effective thermal management, which is crucial for optimising mould filling, solidification, cycle times, and part quality. Against this background, this study presents the development and characterisation of a cooling system that completely dispenses with energy-intensive heating/cooling devices. The system is based on a mask shape combined with internal spray cooling. This paper shows the simulation workflow for developing the mould mask and the design of the cooling system and compares the performance with conventional temperature control using channels. In the tests, an 82% higher cooling rate was achieved with Cool-Spray than with conventional temperature control, which was approx. 2.5 mm below the cavity surface. In addition to the more dynamic temperature control, the potential for process control was utilised, and the component quality of the test part was significantly improved compared to conventional temperature control. [ABSTRACT FROM AUTHOR]

In recent years, Non-Heat Treatable High Pressure Die Casting Al alloys (NHT-HPDC Al alloys) have been proposed and developed for integrated die casting in the automotive industry. These alloys exhibit excellent castability and can achieve sufficient mechanical properties without the need for heat treatment. Despite their industrial significance, there is a lack of an updated and comprehensive description of such alloys. The insufficient availability of literature and the absence of a systematic design mentality have hindered their development. Therefore, this study reviews several aspects of NHT-HPDC Al alloys. Firstly, the NHT-HPDC Al alloys are divided into Al-Si, Al-Mg-Si and Al-Fe-Mg alloys, with the NHT-HPDC Al-Si alloys being the mainstream. The solidification behaviors of NHT-HPDC Al-Si-(Cu)-(Mg) alloys are discussed using phase diagram analyses. Secondly, the manipulation of critical phases is discussed, including: (i) impurity phase: Fe-rich phase (the neutralization treatment); (ii) strengthening phases: Eutectic Si phase (the modification treatment)/main alloying elements regulating phases/trace alloying elements regulating phases/ceramic particles. Thirdly, the typical three regions of NHT-HPDC Al-Si components and their formation mechanisms are identified and reviewed. Then, the influence of vacuum assistance and intensification pressure to the general quality of NHT-HPDC Al-Si components is comprehensively discussed. Finally, future challenges for NHT-HPDC Al-Si alloys are also proposed. [ABSTRACT FROM AUTHOR]

The wear and degradation of tools applied in the high-pressure die casting of Al alloys induce significant financial losses. The formation of failures on the surface of mold parts caused by erosion, thermal fatigue, corrosion, and soldering negatively affects the surface quality of castings. In this study, the lifetime of inserts protected by physical-vapor-deposited coatings (TiN, TiAlN, and CrAlSiN) is examined under real manufacturing conditions while considering requirements for the castings' surface quality (maximum average roughness Ra) defined by the customer. The goal was to identify the most suitable solution for HPDC in the foundry organization. After the deposition of PVD coatings on the inserts, the hardness (HRC) values increased from two to five depending on the coating used, and also the surface roughness was higher in the case of all inserts (Ra values increased from 0.24 to 0.36 µm). The lifetime of all PVD-coated inserts was higher compared to the uncoated insert. The highest lifetime was achieved by the application of a TiN coating, when 15,000 shots were achieved until the inserts' wear negatively affected (increased) the surface roughness of castings, considering the customer requirements for the maximum Ra value. SEM analysis was used to identify examples of wear and degradation on the surface of the TiN coated insert. [ABSTRACT FROM AUTHOR]

In this study, the microstructure, hardness, tensile strength, and dry wear properties of the cast AlSi10Mg alloy as well as the effects of processing parameters on the oxidation behavior of this alloy were investigated. In this context, AlSi10Mg (wt%) alloy was produced by gravity die casting method, and then, air cooling, quenching, and T6 treatment were applied. The microstructure of the alloy was investigated using an optical microscope, SEM, and EDS. Additionally, thermogravimetric analysis (TGA) was used to determine the effect of processing parameters on the oxidation behavior of the samples. The friction and wear properties of the alloy were investigated using a ball-on-disk wear test device. It was founded that the as-cast AlSi10Mg alloy's microstructure contained phases of α(Al), Si, and β-Mg2Si. It has been observed that the microstructure of the cast AlSi10Mg alloy gradually turns into a spherical form when quenching and air-cooling heat treatments are applied. Also, T6 heat treatment led to further spheroidization of Si particles, formation of β-Mg2Si precipitates, and elimination of the Chinese script morphology of the β-Mg2Si phase. It was observed that the yield strength of the AlSi10Mg alloy in the as-cast state decreased negligibly compared to the air-cooled state, while there was an increase of up to 70% in the aging-treated condition. The results show that the tensile strength of the as-cast AlSi10Mg alloy increased by 115% after aging. Additionally, it was found that the AlSi10Mg alloy's wear resistance increased with the aging process. [ABSTRACT FROM AUTHOR]

Rotary transfer machines are widely used in different industrial sectors. A rich literature concerning their design and optimisation is available, but mainly dedicated to integrated machining systems. This machine architecture is also implemented in the aluminium gravity die casting technology where the specificity of the casting process needs an appropriate design. In particular, the constraints related to processing times and the rigidity of the production sequence impose a specific approach to schedule the production for achieving an optimal cycle time. We approach this problem with an optimisation perspective: first we propose a mixed-integer linear programming formulation for defining the sequencing and scheduling of the machine in order to obtain a specified production with minimum makespan, and discuss strategies for enumerating the variables of the formulation. Second, we describe a heuristic algorithm as an alternative to the solution of the formulation through a general-purpose solver. Eventually, we present extensive computational experiments on a set of instances generated from real data, comparing these alternative approaches. [ABSTRACT FROM AUTHOR]

In the fields of plastic injection molding and die metal casting, drilling cooling channels into the molds had, until recently, been the only way to form a cooling channel within these molds. With the advent of selective laser melting (SLM), conformal cooling channels have been designed and manufactured to follow the shape of the mold. However, it is challenging to fabricate millimeter-scale channels by SLM due to manufacturing limitations. Unmelt powders and unsupported surfaces result in high roughness and clog of channels, especially when the diameter is less than 2 mm. This work aims to show how the diameters and roughness of 1- to 4-mm-scale cooling channels made by SLM affect their cooling performance. A chemical etching process was used to polish the internal surface of the cooling channels. The etching results in this research show that low-concentration (6% by mass) hydrochloric acid can effectively reduce the roughness of aluminum channels manufactured using a selective laser melting printer. Temperature data was collected and analyzed to show how the diameter roughness of the channel affects heat transfer. It was found that reduced roughness can improve the heat transfer performance for the 2-mm cooling channel. However, with the increase of the pressure and diameter, the heat transfer improvement by etching was reduced. The untreated cooling channels outperformed the etched ones for the 3-mm cooling channels under a high inlet pressure. [ABSTRACT FROM AUTHOR]

The objective of the present investigation is to synthesise and characterise the Cu-Al-Ag shape memory alloys with minor Mn addition. Synthesis of Cu-Al-Ag-Mn SMA was done by induction furnace and gravity die casting, with constant Ag/Mn ratio (5% Ag and 2% Mn), the aluminium composition is varied from 8% to 14%. The as-cast sample will be further subjected to thermo-mechanical treatment to produce a sheet which exhibits shape memory effect. This study is to determine the influence of Al content on shape memory characteristics, microstructure, and phase transformation temperatures. The phase fraction of β'1 increased from 56% to 67% along with subsequent reduction of γ1' phase fraction from 23% to 17%, which is essential for improvement of shape memory properties with increase of aluminium constituent. X-ray diffraction revealed that the crystalline size decreased 79 to 32 nm and lattice strains increased from 0.24% to 0.69% with increase of Aluminium. With an increase in aluminium content, the martensite transformation temperature decreased from 386°C to 246°C, and the shape memory effect increased from 81 to 90% strain recovery. The ability to control shape memory characteristics by changing Al composition will improve the scope for this alloy in various shape memory applications. [ABSTRACT FROM AUTHOR]

RTV 10A silicone rubber composites have many applications in forming many medical products and one of the recent applications is for orthotic insoles. This is because the RTV silicon rubber has excellent flexibility, elasticity, and resistance against splitting. However, these mechanical properties still need improvement when applied in certain medical applications. One way to improve mechanical properties is by adding talc. The process of mixing silicon rubber with talc requires special techniques to prevent the formation of porosity that may lead to unexpected mechanical properties. This porosity occurs due to trapped air during the mixing process or pouring into molds. Efforts to eliminate this porosity include vacuum die casting (VDC) techniques. This study presents the mechanical properties improvement of RTV 10A silicon rubber composite with the addition of using 30% talc. The objective is to achieve a more convenient orthotic insole to reduce the pain in human foot joints during walking due to planar stress. This study aims to reduce the porosity and minimize the trapped air by adding 30% talc into RTV 10A silicone rubber composite using VDC. In the experiment, the pressure variation was determined at -0.04 MPa, -0.06 MPa, -0.08 MPa, and -0.1 MPa through a mold size of 45 mm in diameter and thickness of 7 mm. Fluidity, density, porosity, and hardness were tested during the experiment. The results show that by decreasing vacuum pressure, the density and the hardness increase. This is because the size and distribution of porosity are decreased and more homogeny. Furthermore, it also produces higher fluidity. However, the porosity of the specimen after vacuum casting is not partially filled. [ABSTRACT FROM AUTHOR]

PURPOSE: To compare and evaluate vertical displacement, lateral displacement and pressure during peri implant tissue displacement using 3 different displacement methods. MATERIALS AND METHODS: Ten single piece implants were placed and provisional crowns were given. After a period of six months, primary impressions were made and casts were poured. Over these casts, custom trays were fabricated (n=40). A Pre displacement impression was followed by Mechanical (G cuff), Chemical (astringent retraction paste) and Chemicomechanical (knitted retraction cord) displacement in a gap of seven days. Pressure measurements were made using customized pressure sensitive periodontal probe. Impressions were made and the forty die stone casts obtained were scanned and analysed to measure the vertical and lateral displacement. The statistical analysis was done using Kruskal Wallis test followed by Post Hoc analysis - Scheffe’s method. RESULTS: The highest vertical displacement was seen in Chemicomechanical (knitted retraction cord) followed by Mechanical (G-cuff) and Chemical (astringent retraction paste). The highest lateral displacement was seen in Mechanical (G cuff) followed by Chemico-mechanical (knitted retraction cord) and Chemical (astringent retraction paste). Least pressure was seen with chemical (astringent retraction paste) method followed by mechanical (G cuff) and chemico – mechanical (knitted retraction cord) method. CONCLUSION: Lateral peri implant displacement is more predictable than vertical peri implant displacement. All the methods tested showed pressure within acceptable limits during displacement procedures. Chemical (Astringent retraction paste) method produced desirable displacement with least pressure to the surrounding tissues. [ABSTRACT FROM AUTHOR]

The continuous industrial development that occurs worldwide generates the need to develop new materials with increasingly higher functional properties. This need also applies to the basic material for electricity purposes, which is copper. In this article, we carry out studies on the influence of various alloying elements such as Mg, In, Si, Nb, Hf, Sb, Ni, Al, Fe, Zr, Cr, Zn, P, Ag, Sc, Pb, Sn, Co, Ti, Mn, Te and Bi on the electrical and mechanical properties of ETP-grade copper. The research involves producing copper alloys using the gravity die casting method with alloy additions of 0.1 wt.%, 0.3 wt.% and 0.5 wt.%. All resulting materials are cold-worked to produce wires, which are subsequently homogenized and annealed. The materials produced in this manner undergo testing to determine their specific electrical conductivity, tensile strength, yield strength, elongation and Vickers hardness (HV10 scale). [ABSTRACT FROM AUTHOR]

The low-pressure die casting (LPDC) process was experimentally and numerically studied to produce AlSi7Mg0.3 components such as steering knuckles. Steering knuckles are important safety components in the context of a vehicle's suspension system, serving as the mechanical interface that facilitates the articulation of the steering to control the front wheel's orientation, while simultaneously bearing the vertical load imposed by the vehicle's weight. This work focuses on the development of a numerical model in ProCAST®, replicating the production of the aforementioned part. The model analyses parameters such as the filling dynamics, solidification process, and presence of shrinkage porosities. For the purpose of evaluating the quality of the castings, six parts were produced and characterised, both mechanically (tensile and hardness tests) and microstructurally (porosity and optical microscopy analysis). When correlating simulation results with the available experimental data, it is possible to conclude that the usage of the LPDC process is a viable alternative to the use of steels and other metals for the production of very high-quality castings while using lighter alloys such as aluminium and magnesium in more demanding applications. [ABSTRACT FROM AUTHOR]

Magnesium-based multicomponent alloys with different compositions, namely Mg60Al20Zn5Cu10Mn5 (Mg60 alloy), Mg70Al15Zn5Cu5Mn5 (Mg70 alloy), and Mg80Al5Cu5Mn5Zn5 (Mg 80) alloys, were prepared using the disintegrated melt deposition technique. The DMD technique is a distinctive method that merges the benefits from gravity die casting and spray forming. This approach facilitates high solidification rates, process yields, and reduced metal wastage, resulting in materials with a fine microstructure and minimal porosity. Their potential as biodegradable materials was assessed through corrosion in different simulated body fluids (SBFs), microstructure, and cytotoxicity tests. It was observed that the Mg60 alloy exhibited low corrosion rates (~× 10−5 mm/year) in all SBF solutions, with a minor amount of corrosive products, and cracks were observed. This can be attributed to the formation of the Mg32(AlZn)49 phase and to its stability due to Mg(OH)2 film, leading to excellent corrosion resistance when compared to the Mg70 and M80 alloys. Conversely, the Mg80 alloy exhibited high corrosion rates, along with more surface degradation and cracks, due to active intermetallic phases, such as Al6Mn, Al2CuMg, and Al2Cu phases. The order of corrosion resistance for the Mg alloy was found to be ASS > HBSS > ABP > PBS. Further, in vitro cytotoxicity studies were carried out using MDA-MB-231 tumor cells. By comparing all three alloys, in terms of proliferation and vitality, the Mg80 alloy emerged as a promising material for implants, with potential antitumor activity. [ABSTRACT FROM AUTHOR]

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This study presents the development and process integration of an alternative demoulding system for high-pressure die casting. The system is aimed at the removal of large structural castings, which are becoming increasingly popular in the industry under the terms mega- and gigacasting. The development differs from conventional systems in the fact that it completely avoids ejectors and realises the demoulding via the principle of vacuum suction cups. Preliminary tests were carried out in which various established materials for vacuum cups were initially identified and the suitability of the selected cup concept was investigated by varying influencing variables from the high-pressure die casting. These tests showed that a suction pad material combination of an elastomer with a thermal barrier and an aramid felt on the surface provides the best results under the given process boundary conditions. Based on this, a multi-segmented vacuum mask with contour adaptation to the casting to be removed was developed. This vacuum mask is used to build up the holding force between the casting and the removal device. The necessary removal force is applied via pneumatic cylinders. The functional capability of the concept and the system integration was verified by experiments on a real die-casting mould for test specimens. The shrinkage and demoulding process can be successfully modelled in the simulation and the real measured demoulding force is only approx. 15% higher than in the simulation. During demoulding in the high-pressure die-casting process, vacuums of up to 88.7% were achieved at temperatures up to 395 °C. [ABSTRACT FROM AUTHOR]

The European Green Deal poses a two-pronged challenge for the automotive industry: migrating to solutions based on light structures, requiring lightweight concepts and light materials, while at the same time avoiding dependence on the importation of these advanced materials. Aluminium alloys are lightweight and cost-effective materials that can successfully meet the requirements of many structural applications; however, their production requires bauxite and other Critical Raw Materials (CRMs), such as Si and Mg. Aluminium alloys are fully recyclable, but scrap is usually contaminated and its use is related to an increment of impurities, tramp elements and undesired inclusions. Traditionally, the use of secondary alloys has been restricted to low-performance applications. The present work analyses the effect that the use of scrap has on the quantity of inclusions present in the alloy and on other properties relevant for material processing. This study was carried out using common alloys associated with three of the most common aluminium processes used in the car manufacturing industry: high-pressure die casting (HPDC) (AB-43500), extrusion (6063) and sheet metal forming (5754 and 6181). The reference alloys were mixed with different levels of scrap (0, 20, 40, 60, 80 and 100%), with an aim to keep the chemical composition as unaffected as possible. The inclusion level of the alloy was characterized using the Prefil Footprinter® test. In addition, the obtained materials, after being cast in an open mould, were subjected to metallographic characterization. Relevant properties were measured to assess the processability of the alloys for the corresponding transforming process using the flowability test for the HPDC alloy and high-temperature compression for the extrusion alloys. The results obtained suggest that the number of inclusions present in the melt highly increase with the amount of scrap used to produce the alloy. These inclusions are also related to a significant loss of flowability, but do not have a noticeable impact on microstructure. [ABSTRACT FROM AUTHOR]

The demand for lightweight and cost-effective heat sinks is increasing. A typical method for economically manufacturing complex-shape heat sinks is die casting. To reduce the weight of the die-cast heat sinks, thinning the fins and base is common practice. We experimented with casting heat sinks using Al-25%Si in a conventional die casting machine with the aim of economically producing thinner fins and bases. Compared with the aluminum alloy used in conventional die casting, Al-25%Si has superior fluidity, which is proven to be very useful for reducing the thickness of the fins and base. As a result, we successfully reduced the heat sink weight using Al-25%Si and a conventional die casting machine. To investigate the properties of the produced Al-25%Si thin fin heat sink, we compared the effects of fin thickness, fin height, number of fins, and base thickness on heat dissipation and weight reduction. Additionally, we compared the weight and heat dissipation properties with those of a commercial heat sink and found that our Al-25%Si heat sink maintains the same heat dissipation performance but for 35% lower weight. [ABSTRACT FROM AUTHOR]

Die casting has many advantages, such as high precision, mass production, and excellent recyclability. However, gas defects in the product have become a problem. One countermeasure to this problem is to design the injection input of the plunger appropriately. Recently, CFD has been used to design plunger injection inputs, and by combining with optimization techniques, auto-design of plunger injection inputs has been possible. However, CFD is difficult to apply because of the high cost of CFD resources, the need to resource IT engineers, and the time required for its auto-design. Therefore, we propose a new injection input design method based on an algebraic approach, enabling anyone to design a plunger injection input that prevents gas defects with ease and at a low cost. Simulation and experimental results verified the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Detection and characterization of hidden defects, impurities, and damages in homogeneous materials like aluminum die casting materials, as well as composite materials like Fiber–Metal Laminates (FML), is still a challenge. This work discusses methods and challenges in data-driven modeling of automated damage and defect detectors using measured X-ray single- and multi-projection images. Three main issues are identified: Data and feature variance, data feature labeling (for supervised machine learning), and the missing ground truth. It will be shown that simulation of synthetic measuring data can deliver a ground truth dataset and accurate labeling for data-driven modeling, but it cannot be used directly to predict defects in manufacturing processes. Noise has a significant impact on the feature detection and will be discussed. Data-driven feature detectors are implemented with semantic pixel Convolutional Neural Networks. Experimental data are measured with different devices: A low-quality and low-cost (Low-Q) X-ray radiography, a typical industrial mid-quality X-ray radiography and Computed Tomography (CT) system, and a state-of-the-art high-quality μ-CT device. The goals of this work are the training of robust and generalized data-driven ML feature detectors with synthetic data only and the transition from CT to single-projection radiography imaging and analysis. Although, as the title implies, the primary task is pore characterization in aluminum high-pressure die-cast materials, but the methods and results are not limited to this use case. [ABSTRACT FROM AUTHOR]

With an inherent lowest density and distinct solubility with enhanced mechanical behavior reason, the magnesium alloy composite is extensively used in the auto and aero sectors. The processing of magnesium alloy found micro‐cracks and voids between the oxidation spot, which fails properties. Through the sulfur hexafluoride (SF6) atmosphere, the AZ91D alloy hybrid nanocomposites are synthesized with 10 wt% alumina (Al2O3) and 0, 3, 6, and 9 wt% of silicon carbide (SiC) nanoparticles via a liquid state process with 400 rpm stir speed followed by vacuum die casting. The effect of SiC actions on physical behavior, microstructural formation, and mechanical properties of AZ91D/10 wt%Al2O3, AZ91D/10 wt%Al2O3/3 wt% SiC, AZ91D/10 wt% Al2O3/6 wt% SiC, and AZ91D/10 wt% Al2O3/9 wt% SiC composites are studied and its results compared with cast AZ91D alloy. Due to the actions of SiC in AZ91D/10 wt%Al2O3, the composite density conforms to the rule of mixture, and the void and micro‐cracks are limited (less than 1%) by the impact of the casting process, as evidenced in the microstructural illustration. An effect of 10 wt% Al2O3 and 9 wt% SiC contents in AZ91D facilitates maximum tensile strength of 181 MPa, improved elongation percentage of 2.2%, optimum hardness of 85HV, and superior impact toughness of 21.8 J/mm2, which is higher than the all other compositions. [ABSTRACT FROM AUTHOR]

Conventional cooling channels used in die casting molds exhibit significant drawbacks, resulting in extended cooling times for cast parts. Issues such as the formation of dirt, limescale, and corrosion substantially diminish the thermal efficiency of these channels, leading to challenges in achieving uniform cooling and potential quality issues. In response to these challenges, this study proposes Topology Optimization as a novel approach. It involves designing cooling structures through Topology Optimization to replace traditional cooling channels, incorporating both Discrete and Gaussian boundary conditions to optimize thermal efficiency. Additionally, Structural Topology Optimization is employed to ensure structural integrity, preventing deformation or yielding under high loads during the die casting process. Numerical analysis revealed superior thermal performance compared to conventional channels, particularly when subjected to Discrete and Gaussian boundary conditions. Furthermore, the application of the latter establishes conformal cooling and minimizes temperature gradients in the casting, reducing casting defects such as shrinkage porosity. These findings highlight the efficacy of Topology Optimization in addressing the challenges of traditional cooling methods, with wide-ranging implications for manufacturing processes utilizing permanent molds for shaping materials. [ABSTRACT FROM AUTHOR]

Many practical high-pressure die casting process (HPDCP) optimization problems are multi-objective optimization ones that optimize multiple quality attributes of castings, simultaneously. This paper proposed a new HPDCP optimization method for improving volume of shrinkage porosity (VSP) and air entrainment (AE) using Taguchi-based ProCAST simulation and multi-attribute decision-making (MADM)-based overall quality index. Taguchi orthogonal array was used to design ProCAST simulation experiment. MADM was used to convert multiple quality attributes into a single overall quality index (OQI). Taguchi optimization method was used to determine the optimal HPDCP parameters to maximize the OQI. By using the proposed method, this paper determined the optimal HPDCP parameters such as pouring temperature (PT), filling rate in shot sleeve (FR), piston velocity (PV) and preheating mold temperature (PMT) for improving the VSP and AE in carburetor housing with aluminum alloy AlSi9Cu1Mg. The optimal HPDCP parameters were PT of 640 °C, FR of 40%, PV of 6.5 m/s, and PMT of 150 °C. The PT was the most effective HPDCP parameter for improving the VSP and AE, and the next were FR, PV, and PMT. The proposed method could be actively applied to not only HPDCP but also other casting processes and other manufacturing processes. [ABSTRACT FROM AUTHOR]

• Gd addition to the Mg-4Al-5RE alloys produced by various casting methods can refine the grains and modify the morphology of the acicular Al11RE3 phase to the short rod-like. • Gd addition increases the impact toughness due to the lower tendency of the modified second phases toward crack initiation. • The fine-grained HPDC alloys have an inconsistent strain rate sensitivity during the impact event. • The fine-grained HPDC alloys have excellent impact toughness but show an insufficient plastic deformation capacity. This work investigated the microstructure and impact behavior of Mg-4Al-5RE-xGd (RE represents La-Ce mischmetal; x = 0, 0.2, 0.7 wt.%) alloys cast by high-pressure die casting (HPDC), permanent mold casting (PMC), and sand casting (SC) techniques. The results indicated that with increasing Gd content, the grain sizes of the HPDC alloy had a slight change, but the grains of the PMC and SC alloys were significantly refined. Besides, the acicular Al 11 RE 3 phase was modified into the short-rod shape under the three casting conditions. The impact toughness of the studied alloy was mainly dominated by the absorbed energy during the crack initiation. With increasing Gd content, the impact toughness of the studied alloy monotonically increased due to the lower tendency of the modified second phase toward crack initiation. The impact stress was higher than the tensile stress, exhibiting a strain rate sensitivity for the mechanical response; however, the HPDC alloy had an inconsistent strain rate sensitivity during the impact event due to the transformation of the deformation mechanism from twinning to slip with increasing strain. Abundant dimples covered the fracture surface of the fine-grained HPDC alloys, indicating a typical ductile fracture. Nevertheless, due to the deficient {10 1 ¯ 2} twinning activity and the suppressed grain boundary sliding during the impact event, the HPDC alloys showed insufficient plastic deformation capacity. [ABSTRACT FROM AUTHOR]

This study optimized the integrated die-casting of an aluminum alloy longitudinal beam and tower component using no heat-treated aluminum alloy. Leveraging material properties and part geometry, a pouring system was designed and refined through mold flow analysis. This optimized the velocity, temperature distribution, and air entrapment to reduce defects like shrinkage porosity. The optimized pouring parameters were 695 °C melt temperature, 210 °C initial mold temperature, and 4.9 m/s shot speed. This reduced shrinkage porosity by 10.4% versus the original design. Die-casting trials with the optimized pouring system produced defect-free castings. The critical load-bearing section of the die casting had a yield strength of 184 MPa and elongation of 10.9%, which can meet the production requirements. In summary, based on the optimization of pouring system by mold flow analysis, by developing the integrated die casting process for aluminum alloy, not only are the defects eliminated, but also the castings with sufficient mechanical properties are produced. [ABSTRACT FROM AUTHOR]

High-pressure die casting (HPDC) components exhibit unique sandwich microstructural features along the thickness direction, thereby displaying solute distribution patterns distinct from those of components produced through alternative casting methods. Considering the notable influence of solute atoms on thermal conductivity, relying solely on the local microstructure to characterize the thermal conductivity of HPDC components is an incomplete approach. This work investigated the effect of thickness-dependent sandwich microstructure on the thermal conductivity of an HPDC model alloy (Mg–4Sm–2Al). The results reveal that the volume fractions of distinct layers (TSkin/T, TCore/T and TSB/T) remain constant as plate thickness increases. Nevertheless, the solute atom concentration within the skin layer gradually decreases as plate thickness increases, a phenomenon attributed to the reduced solidification rate, which allows sufficient time for solute atom precipitation. Intriguingly, within the core layer, solute atom concentration follows a nonlinear pattern, decreasing and then increasing. The varied distributions of externally solidified crystals (ESCs) are primarily responsible for this paradoxical increase. As plate thickness increases, the ESCs transform from a clustered core distribution to a uniform through-thickness distribution, progressively altering the solidification behavior of the alloy. Concurrently, an effective model for the sandwich microstructure that considers interactions among solute atoms within the α-Mg matrix is proposed. This model successfully characterizes the thermal conductivity of HPDC alloys and finds application in Mg–Sm–Al system alloys, with a relative error of less than 15 pct between the predicted and experimental results. [ABSTRACT FROM AUTHOR]

With the unique class, the reinforcements play a precious role during the composite fabrication, expanding the specific properties. The novel research intensively enhances the micro-structural and mechanical behaviour of magnesium alloy (AZ63/3 wt% boron nitride) nanocomposite featured 2, 4, and 6 wt% of nano-size silicon carbide (SiC) particles via liquid state vacuum stir cast route. The exposure of SiC and BN on composite density, voids contribution, changes in AZ91D microstructure, impact toughness, hardness, and stress-strain individuality of AZ63 alloy nanocomposite is evaluated with ASTM policy. The composite composed with 3 wt% BN and 6 wt% SiC proved their identity. It showed the lower contribution of voids-free homogenous dispersion particle results in a maximum impact strength of 14.7J/mm2, hardness of 74HV, and superb tensile strength of 247MPa. This optimum behaviour will be recommended for automotive roof frame applications. [ABSTRACT FROM AUTHOR]

This research paper examines the effect of different solution heat treatments parameters (temperature and time) on Al–3.39%Cu–2.26%Mg (wt%) alloy's microstructure, thermal, mechanical and corrosion properties. 5754 alloy and Al–Cu alloy are used to make Al–3.39%Cu–2.26%Mg (wt%) by gravity die casting. Solution heat treatment at different temperature and time (500 °C-10 min, 500 °C-4h, 530 °C-10 min and 530 °C-2h). As-cast Al–Cu–Mg alloy have α-phase and eutectic phase. After solution heat treatment and aging, precipitates phases is observed in microstructure. X-ray diffraction analysis results have shown that a precipitate phase [S phase (Al2CuMg)] gets formed in as-cast conditions but undergoes dissolution during the solution heat treatment process. As-cast Al–Cu–Mg alloy has a Brinell hardness value of 77.2 HB. As-cast alloy has S (Al2CuMg) precipitate phase increases hardness by precipitation strengthening. After solution heat treatment and aging, Brinell hardness reduces. After solution heat treatment (500 °C for 4 h) and aging (200 °C for 5 h), Brinell hardness values becomes 63.6 HB (− 17.6% decrease). Corrosion resistance improves after the solution heat treatment due to the dissolution of the precipitate phase, forming an almost single-phase solid solution. The as-cast alloy exhibits a peak compressive stress of 494.2 MPa, which increases after solution heat treatment and water quenching to 572.7 MPa (without aging). After aging, peak compressive stress decreases to 508.4 MPa. Failure strain for the as-cast alloy is 39.6%, reducing to 31.1% after solution heat treatment and water quenching. It again increases to 43.1% after aging. [ABSTRACT FROM AUTHOR]

• Identification of the most influencing factor (Mn) for the sludge yield in Mg-Al alloys. • Intermetallic size in the sludge determined primarily by the holding temperature as well as the Al and Mn contents. • Establishment of sludge factors for Mg alloys with multivariate linear regression analyses; and. • Sludge factor equations making the sludge yield and intermetallic size in Mg-Al alloys predictable, which can avoid sludge buildup in holding crucibles, hard spots in cast components, reduced fluidity of liquid metal to flow into a die during casting. Intermetallic formation in sludge during magnesium (Mg) melting, holding and high pressure die casting practices is a very important issue. But, very often it is overlooked by academia, original equipment manufacturers (OEM), metal ingot producers and even die casters. The aim of this study was to minimize the intermetallic formation in Mg sludge via the optimization of the chemistry and process parameters. The Al 8 Mn 5 intermetallic particles were identified by the microstructure analysis based on the Al and Mn ratio. The design of experiment (DOE) technique, Taguchi method, was employed to minimize the intermetallic formation in the sludge of Mg alloys with various chemical compositions of Al, Mn, Fe, and different process parameters, holding temperature and holding time. The sludge yield (SY) and intermetallic size (IS) was selected as two responses. The optimum combination of the levels in terms of minimizing the intermetallic formation were 9 wt.% Al, 0.15 wt.%Mn, 0.001 wt.% (10 ppm) Fe, 690 °C for the holding temperature and holding at 30 mins for the holding time, respectively. The best combination for smallest intermetallic size were 9 wt.% Al, 0.15 wt.%Mn, 0.001 wt.% (10 ppm) Fe, 630 °C for the holding temperature and holding at 60 mins for the holding time, respectively. Three groups of sludge factors, Chemical Sludge (CSF), Physical Sludge (PSF) and Comprehensive Sludge Factors (and CPSF) were established for prediction of sludge yields and intermetallic sizes in Al-containing Mg alloys. The CPSF with five independent variables including both chemical elements and process parameters gave high accuracy in prediction, as the prediction of the PSF with only the two processing parameters of the melt holding temperature and time showed a relatively large deviation from the experimental data. The Chemical Sludge Factor was primarily designed for small ingot producers and die casters with a limited melting and holding capacity, of which process parameters could be fixed easily. The Physical Sludge Factor could be used for mass production with a single type of Mg alloy, in which the chemistry fluctuation might be negligible. In large Mg casting suppliers with multiple melting and holding furnaces and a number of Mg alloys in production, the Comprehensive Sludge Factor should be implemented to diminish the sludge formation. [ABSTRACT FROM AUTHOR]

High-pressure die casting (HPDC) has been extensively used to manufacture aluminum alloy heat dissipation components in the fields of vehicles, electronics, and communication. With the increasing demand for HPDC heat dissipation components, the thermal conductivity of die-cast aluminum alloys is paid more attention. In this paper, a comprehensive review of the research progress on the thermal conductivity of HPDC aluminum alloys is provided. First of all, we introduce the general heat transport mechanism in aluminum alloys, including electrical transport and phonon transport. Secondly, we summarize several common die-cast aluminum alloy systems utilized for heat dissipation components, such as an Al–Si alloy system and silicon-free aluminum alloy systems, along with the corresponding composition optimizations for these alloy systems. Thirdly, the effect of processing parameters, which are significant for the HPDC process, on the thermal conductivity of HPDC aluminum alloys is discussed. Moreover, some heat treatment strategies for enhancing the thermal conductivity of die-cast aluminum alloys are briefly discussed. Apart from experimental findings, a range of theoretical models used to calculate the thermal conductivity of die-cast aluminum alloys are also summarized. This review aims to guide the development of new high-thermal-conductivity die-cast aluminum alloys. [ABSTRACT FROM AUTHOR]

The space simulation manufacture of Ti61.1Co28.1Al10.8 alloy from three original states including superheated liquid, undercooled liquid, and semi-solid alloy was accomplished by electromagnetic levitation coupled with die casting (EML-DC) technique. The microscopic segregation was eliminated through remarkable solute trapping under the effects of electromagnetic stirring, microgravity processing and rapid die casting. The hierarchical microstructures with both phase constitution difference and grain size gradient were formed due to the high pressure and rapid quenching by die casting. Furthermore, the efficient modulation of this hierarchical microstructure was achieved by adjusting the original states of alloy before die casting. The hierarchical microstructures displayed gradient micromechanical properties. The ultrafine ternary eutectics at the surface region exhibited high elastic recovery, whereas the microstructures composed of primary TiCo dendrites and TiCo + (βTi) eutectics at the middle region showed lower elasticity but higher hardness. [ABSTRACT FROM AUTHOR]

To enhance the performance of ultra-high voltage power fittings in severe weather conditions without altering their current structure, the high-strength and toughness aluminum alloys were rationally selected to study the optimization of the die-casting process. This approach aims to improve the overall longevity and function of the power fittings in extreme climates. First of all, the propose of this study is to use the material's strength–toughness product (STP) concept to evaluate the material stability of the power fitting impact resistance and fatigue toughness in order to determine the appropriate material selection. Secondly, the location of the mold's sprue and gate was optimized through finite element simulation to prevent gas volume and flow defects during the casting process. This improves the material's toughness and anti-fatigue failure characteristics of the product. Then, vacuum equipment and a vacuum valve auxiliary system were added based on the existing die-casting machine, and the mold structure was optimized to enable the vacuum die-casting process. Finally, a water-based boron nitride environmentally friendly mold release agent was used to solve demolding difficulties with an A356 aluminum alloy and improve mold lubrication and surface quality. The production of quad-bundled spacers using A356 and vacuum die casting has resulted in parts with a tensile strength of at least 250 MPa and an elongation of no less than 7%. This improvement has laid a foundation for enhancing the operational reliability of existing overhead transmission line fittings. [ABSTRACT FROM AUTHOR]

Using 3D scanning, coordinate measuring machine, and roughness measurements we evaluated and compared zinc alloy castings produced in conventionally and additively manufactured shaped mould parts. Tests were conducted on castings from new shaped parts and subsequently after approximately every 100,000 shots. Castings from conventional parts had higher dimensional stability, but both types showed decreasing dimensional deviations over time. Castings from new additively manufactured parts had higher roughness initially, but this improved with use. Overall, there were no significant issues, and the benefits of additive-shaped parts prevailed. However, more testing is needed for a final recommendation for use in real operating conditions, requiring hundreds of thousands more shots. [ABSTRACT FROM AUTHOR]

The article deals with the use of computed tomography, an advanced method for evaluating the quality of aluminium castings. Casting quality is a key factor in ensuring safety and reliability in industrial applications. Computed tomography is a comprehensive method allowing a three-dimensional, high-resolution view of the internal structure of materials. The main focus of this paper is the study of BRACKET REAR aluminium castings, manufactured in two-piece moulds using a high-pressure die-casting technology. In this paper, four castings have been analysed which are produced in one cycle. The focus is on the problem of porosity and open stagnation in the castings. A numerical simulation has also been used to illustrate the occurrence of porosity, which can be used to determine both the occurrence of porosity and the occurrence of unfilled volume. The experimental part of the paper describes the methods used to evaluate the BRACKET REAR castings. The numerical simulation was performed in ProCAST 18.0 to determine the occurrence of porosity in the castings under study. The evaluation of computed tomography was performed in myVGL 3.0 2023 software to analyse the internal defects in the castings. The evaluation focused on assessing internal defects and their subsequent effect on the functionality of the final casting. [ABSTRACT FROM AUTHOR]

Life Cycle Assessment (LCA) is a potent tool for evaluating the ecological consequences of various products and processes. However, with a plethora of LCA software tools (ST) available, selecting the most appropriate tool for a specific application can be quite challenging. This research paper aims to compare two popular LCA Tools, GaBi- a commercial software, and openLCA- an open-source, for a traditional tool manufacturing case study. The comparison considers factors such as userfriendliness, user support, modelling capability, cost, flexibility, comprehensiveness, and functionality. Impact categories representing human health, ecosystem, and resource consumption were chosen. The case study evaluated the Cradle-togate manufacturing of a turbine die made by traditional machining processes and used as a wax injection moulding die for investment casting. The study found that aluminum production and manufacturing were the highest contributors to total environmental impact due to electricity consumption and aluminium waste. The results indicate that each ST has unique features and capabilities suitable for specific applications. We calculated relative deviations as the ratio of maximum to minimum calculated impacts for comparison. Ozone depletion (22.57) and freshwater eutrophication (4.2) had the highest variation. Significant deviations in human toxicity (3.16) were observed using the ReCiPe, while climate change (1.58 and 1.66) was accurately assessed by both CML and ReCiPe. GaBi is found to be the most user-friendly and efficient tool for beginners, with great modelling capability and flexibility to handle complex systems, while openLCA is the most comprehensive tool for analyzing complex systems, grants functionality, and is freely available suggested for experienced users. This research paper provides a comprehensive evaluation of LCA ST for traditional tool manufacturing applications, which can help manufacturers make informed decisions in selecting the most suitable ST for their LCA needs. [ABSTRACT FROM AUTHOR]

This industrial research focuses on the implementation and development of a productive process for an automotive structural component (Shock tower) manufactured by a high-pressure die casting (HPDC) process made of aluminum alloy AuralTM-5. This aluminum alloy has been considered in diverse automotive and aerospace components that do not require heat treatment due to its mechanical properties as cast material (F temper). On the other hand, AuralTM-5 has been designed for processing as HPDC because it is an alloy with good fluidity, making it ideal for large castings with thin-wall thicknesses, like safety structural components such as rails, supports, rocker panels, suspension crossmembers, and shock towers. The mechanical properties that were evaluated for the evaluated components were yield strength, ultimate tensile strength, and elongation. Eight samples were taken from different areas of each produced shock tower for evaluating and verifying the homogeneity of each casting. The samples were evaluated from the first hours after they were manufactured by casting until eight weeks after being produced. This was performed to understand the behavior of the alloy during its natural aging process. Two groups of samples were obtained. One set of components was heat-treated by a water quench process after the castings' extraction and the other set of components was not quenched. Results demonstrated that both sets of components, quenched and not quenched, achieved the expected values for the AuralTM-5 of yield strength ≥ 110 MPa, ultimate tensile strength ≥ 240 MPa, and elongation ≥ 8%. Additionally, this is very important for industry since by not treating the structural components by quenching, there are savings in terms of infrastructure and energy consumption, together with benefits in the environmental aspect by avoiding CO2 emissions and being sustainable. [ABSTRACT FROM AUTHOR]