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The 18th International Conference on Aluminium Alloys (ICAA18) was held in Toyama, Japan from September 4 to 8, 2022, and the special issue entitled "Aluminium and Its Alloys for Zero Carbon Society" was published on Materials Transactions in February 2023 (Vol. 64, No. 2). The biennial conference covered a wide range of current trends in aluminium research; e.g. "modeling and simulation", "casting, solidification, recycling and refining", "additive manufacturing", "foams and composite materials", "mechanical properties and advanced processing", "thermomechanical processing, texture and recrystallization", "heat treatment, phase transformation and precipitation", "corrosion and surface treatments", "joining, emerging processes and multi material" and "advanced characterization". This article briefly reviews selected papers from the conference with significant experimental outcome and discussion on aluminium alloys. The author hopes that these papers are useful for all the researchers who develop next-generation technologies and materials concerning aluminium alloys. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Aluminum-doped paper (AP)-based flexible heater chips are proposed. • The AP heater chips are used as a low-voltage thermal igniter for nanoscale energetic materials (nEMs). • Fully integrated compact systems with remote and selective ignition (RSI) capabilities for nEMs are developed. • The RSI systems are demonstrated to ignite nEMs wirelessly and selectively with a smartphone. Abstract Development of low-voltage driven multifunctional thermal igniters for nanoscale energetic materials (nEMs) is important for extending the application of nEMs to various thermal engineering fields. In this study, highly flexible heater chips capable of generating a sufficient amount of heat to ignite nEMs at a low voltage are demonstrated by incorporating a patterned aluminum-doped paper (AP) with polymeric substrates. A combination of automatic paper cutting and single-step ultraviolet polymer curing techniques helps in the fabrication of various designs of flexible AP heater chips in a simple and low-cost manner. Based on the AP heater chips, three models of flexible thermal igniters are designed to develop new functions such as selective ignition and sequential ignition in a single chip and successfully operated at low voltages. Two types of compact ignition systems are fabricated by fully integrating the arrayed AP igniters, circuit modules, and portable batteries in a three-dimensional printed single package and on a flexible circuit board. The systems are successfully demonstrated to ignite nEMs wirelessly and selectively with a smartphone. [ABSTRACT FROM AUTHOR]

Al–Cu-based casting alloys have very high strength, but improper heat treatment will create a material susceptible to stress corrosion failure. A review of this problem is provided and discussed regarding a recent study of A205-T7 alloy castings. [ABSTRACT FROM AUTHOR]

The August 2024 issue of the Journal of Materials Science features a cover paper titled "Stabilized CsPbBr3 quantum dots in flower-like LYH matrix for high-performance white light-emitting diodes" by Yanrui Yang and colleagues at Fuyang Normal University in China. The paper explores the production and properties of these materials, with a focus on their luminescence data. The paper is part of the "Chemical routes to materials" Topical Collection, but could also be relevant to the "Electronic materials" Topical Collection. The article is freely accessible online through the SharedIt link provided. The publisher, Springer Nature, maintains a neutral stance on jurisdictional claims and institutional affiliations. [Extracted from the article]

The June 2024 cover image of the Journal of Materials Science features a paper by Liss et al. titled "Recrystallization of bulk nanostructured magnesium alloy AZ31 after severe plastic deformation: an in situ diffraction study." The image is an artistic representation of nanostructured magnesium alloy AZ31 undergoing heating, showcasing the process of recrystallization in reciprocal space. The paper is part of a Special Issue on "Processing Bulk Nanostructured Materials," which includes a total of 28 articles covering various aspects of severe plastic deformation (SPD) in the processing of bulk nanostructured materials. The Special Issue aims to highlight the enduring significance and resilience of research in this field. Both the paper and the preface of the Special Issue have SharedIt links for easy sharing with readers. [Extracted from the article]

The contact angle (CA) of a water droplet on the polished aluminum surfaces is usually between 60° and 90°. This paper discusses a tuned bulk micro-manufacturing approach for transforming the surface topology of aluminum simultaneously at the micro- and nano-length scales, thereby significantly influencing its wetting characteristics. The approach is cheap, easy to implement, and scalable. The treated aluminum surfaces appeared like roughly polished surfaces at the macroscale and were found to be robust and non-toxic. They exhibited a paper towel effect by showing extreme surface wettability (CA of zero) to many industrial liquids, i.e., wetting on these surfaces is only a function of the surface roughness but not the fluid type. This extreme wetting ability to multiple liquids (or ultra-omniphilicity) was generated by sequentially creating a sub-surface micro- and nano-cavity architecture with nano-cavities within the embryos of micro-cavities interconnected by a network of micro-grooves. [ABSTRACT FROM AUTHOR]

The May 2024 issue of the Journal of Materials Science features a cover paper titled "Role of stacking fault energy in confined layer slip in nanolaminated Cu" by Ji et al. The paper explores the deformation of metallic nanolaminates and acknowledges the contribution of Professor Hussein Zbib. The issue is dedicated to honoring Professor Zbib's memory and was conceived by Guest Editors Tariq Khraishi, Georges Ayoub, Sinisa Mesarovic, and Mutasem Shehadeh. The paper includes references to previous work but does not mention any measurements of the intrinsic stacking fault energy. The corresponding author is Professor Shuozhi Xu from the University of Oklahoma, and the last author is Professor I.J. Beyerlein, who has a background in research and was born in Los Alamos. The paper is freely accessible through the SharedIt link provided. [Extracted from the article]

Milling force during machining process has strong time-varying and multi-frequency characteristic, which is easy to cause tool vibration, wear, and cutting chatter, and even lead the machining accuracy of parts to be out of tolerance. The paper proposed a milling force prediction method for a general helix cutter during peripheral milling. In this model, the geometric parameters of milling cutter are parametric defined, and then an analytical instantaneous uncut chip thickness (IUCT) model is presented with taking cutter runout (offset and inclination) and geometric entity shape of workpiece into account. A series of milling experiments using aluminum alloy were carried out with six kinds of milling cutters in a high-speed machining center. The analysis results show that the predicted value of milling force can better reflect the change trend of the actual measured one, and well prove the validity of the presented method. Furthermore, the influences of milling parameters, cutter runout, milling type, cutter tooth number, and unequal spacing angle on the time domain and frequency domain excitation characteristics of milling force are systematically analyzed, which can provide useful guidance for the tool design and machining parameter selection in the future. [ABSTRACT FROM AUTHOR]

The article presents the results and process analysis of the face milling of aluminium alloy 2017A with the CoroMill 490 tool on an AVIA VMC 800 vertical milling centre. The study analysed the effects of the cutting speed, the feed rate, the actual number of teeth involved in the process, the minimum thickness of the cut layer (hmin), and the relative displacement in the tool-workpiece system D(ξ) on the surface roughness parameter Ra. To measure relative displacement, an original bench was used with an XL-80 laser interferometer. The analysis of relative displacement and surface roughness allowed these factors to be correlated with each other. The purpose of this article is to determine the stable operating ranges of the CoroMill 490-050Q22-08M milling head with respect to the value of the generated relative displacement w during the face-milling process and to determine its influence on surface roughness. The research methodology presented in this paper and the cutting tests carried out allowed the determination of the optimum operating parameters of the CoroMill 490-050Q22-08M tool during the face milling of aluminium alloy 2017A, which are vc 300 m/m and fz—0.14 mm/tooth. Working with the defined cutting parameters allows all the cutting inserts in the tool body to be involved in shaping the geometrical structure of the surface, while maintaining a low vibration level D(ξ) > 1 µm, a low value of the parameter hmin > 1.5 µm, and the desired value of the parameter Ra > 0.2 µm [ABSTRACT FROM AUTHOR]

This document is a summary of a special issue of the journal "Materials" focused on the topic of surface engineering for wear, corrosion, and erosion prevention in metallic and ceramic materials. The special issue includes twelve scientific papers covering various aspects of the operational performance and properties of metallic and ceramic materials. The papers discuss topics such as the effects of peening treatments, corrosion resistance, tribological behavior, and wear improvement through microstructural modification and the deposition of wear-resistant coatings. The special issue received significant interest from authors and readers, leading to the announcement of a second volume on the same topic. The summary acknowledges the need for experimental data in surface engineering to understand the wear and performance of engineering materials. [Extracted from the article]

This document is a special issue of the journal "Materials" that focuses on the recent progress in the structure transition, processing, characterization, and applications of metallic materials. The issue includes research papers on various topics such as the development of dispersion-strengthened copper alloys, the characterization of carbide precipitation in steel, the effect of magnetic fields on aluminum bronze, and the enhancement of impact toughness in cast iron through heat treatment. The issue aims to provide comprehensive and up-to-date information for researchers, engineers, and industry experts in the field of metallic materials. [Extracted from the article]

The February 2024 issue of the Journal of Materials Science features a cover paper titled "Enhancing the impact property of high-entropy alloys with graphene layers: a molecular dynamics study" by Qing-Xiang Pei et al. The paper explores the use of molecular dynamics simulations to study the impact of a projectile on a high-entropy alloy (HEA) containing layers of graphene. The authors highlight the broad interest in their research, as it appeals not only to the modeling community but also to other communities interested in the materials being modeled. The paper provides valuable insights into the behavior of composite materials and includes figures illustrating the preparation of the model material and the interaction between a projectile and the HEA. The article is freely accessible through the SharedIt link provided, and the corresponding authors can be contacted for access to the data. The publisher, Springer Nature, maintains a neutral stance on jurisdictional claims and institutional affiliations. [Extracted from the article]

The solid-liquid interfacial energy is reported as 0.163 [[11]] for Al-Cu alloys with Cu concentrations between 35 and 40wt.%, and 0.172 J/m SP 2 sp [[12]] for an Al-6.4wt.%Ni alloy. The surface tension value of 1.29 N/m is for pure copper at its melting temperature of 1085°C [[5]]; not even the value for the surface tension of pure Al or an Al alloy. Keywords: Dendrite coarsening EN Dendrite coarsening 35 39 5 02/01/22 20220101 NES 220101 Recently, Correa et al. [[1]] conducted experiments on the relationship between solidification parameters, including solidification time I t SB s sb i and secondary dendrite arm spacing I SB 2 sb , i for an Al-3wt.%Cu-3wt.%Ni alloy. [Extracted from the article]

Purpose: The paper aims to produce aluminium welds in the solid state with good specifications and the least amount of welding defects by using the friction stir welding method (FSW) and different tool pin profiles and welding parameters. The research investigated the mechanical characteristics and microstructure of a friction stir welded dissimilar aluminium alloy (2024-T3 to 7075-0) through thickness produced by varying welding settings and three different FSW tool pin shapes. Design/methodology/approach: The objective is to obtain the welds with the least amount of welding defects in the solid state by using the friction stir welding method (FSW), designing the tool pin profiles, and changing the rotation speeds. Findings: According to tensile strength and micro-hardness tests, tool rotation of 2000 rpm and square pin profile were the best compared to other working parameters. The greatest hardness and highest tensile strength of FSWed dissimilar aluminium joints have been 144 HV and 215 MPa, respectively, when using the square pin profile at a tool rotation speed of 2000 rpm. The hardness and tensile strength of FSWed dissimilar aluminium alloy joints increase with the tool rotation speed. Microstructural observations of the FSWed dissimilar aluminium joints using a square pin profile at the tool rotation speed of 2000 rpm exhibited the weld zone's high weld quality. Additionally, there were no defects in the weld zone. The fracture surface of the FSWed joint indicated a ductile fracture type. Research limitations/implications: With many regions on either side of the weld with varied compositions, microstructures, and characteristics, the resulting welds of dissimilar alloys might result in unsatisfactory weld joints. Practical implications: The weld zone's exceptional weld quality was demonstrated by microstructural investigations of the FSWed dissimilar aluminium connections utilising a square pin profile at a tool rotation speed of 2000 rpm and feed rate of 20 mm per minute. Application in aerospace, shipbuilding and marine, railway, construction, electrical industries, and land transportation. Originality/value: The original value of the paper is the production of welds from dissimilar aluminium alloy (2024-T3 to 7075-0) with the least amount of welding defects by changing the tool pin profiles and tool rotation speeds using the friction stir welding method. [ABSTRACT FROM AUTHOR]

Featured Application: Towing systems are largely used in the automotive industry. They must respect some requirements defined by the standards. These important systems for cars are studied in this paper in order to improve safety in transportation. The authors present the possibility to use other materials for towbars and formulate a series of practical recommendations obtained as a result of extended studies on towing systems. This paper aims, in the context of the need to reduce the weight and price of vehicles, to present theoretical and experimental results regarding towing systems made of alternative materials (fibrous composite materials and aluminum alloys). The study of the main element of the whole system, namely towbar research, was stressed, presenting comparative results. The FEM will be used to obtain the stress and strain field in the towball and the towing system. The experimental tests validate the theoretical results obtained. This paper studies five towing systems made by different materials and finally presents a series of practical recommendations, useful in the industry, regarding the improvement of the analyzed models. [ABSTRACT FROM AUTHOR]

Featured Application: This paper develops an innovative post-weld composite treatment process, which can significantly improve the formability of aluminum alloy tailor welded blanks compared with the traditional single post-weld treatment method. The mechanical properties and cross-sectional geometric dimensions of the fusion zone (FZ), heat affected zone (HAZ), and base metal (BM) of 6xxx series aluminum alloys are inconsistent after filler wire welding, which reduces the formability of aluminum alloy tailor welded blanks (TWBs). This paper proposes a post-weld cold rolling-solution heat treatment (PWCR-SHT) composite process, and the effects of weld excess metal, plastic deformation, and SHT on the formability of aluminum alloy TWBs are studied. The results show that the PWCR-SHT composite process eliminates the weld excess metal and internal pores, reduces the stress concentration at the weld toe, eliminates the local strain hardening behavior, and causes recrystallization in the FZ region. The cupping value of aluminum alloy TWBs using SHT is 105% of BM, in comparison, the cupping value of aluminum alloy TWBs using the PWCR-SHT composite process is 119% of BM, which is the result of the combined effect of geometric dimensions consistency and mechanical properties consistency. [ABSTRACT FROM AUTHOR]

Friction Stir Processing (FSP) has become a famous solid‐state technology for the fabrication of a wide range of aluminum alloy‐based composites that today find multiple applications across the various metal industries. Generation of revolving, ribbon, bulk, excessive or mass flash as it is generally termed has been a common problem in numerous FSP works. When confronted by this challenge, many researchers apply different experimental and numerical modeling approaches or strategies to reduce the mass flash to practically acceptable limits since it often leads to undesirable loss of material and is also an unwanted defect. This subject is deficiently reviewed, and it therefore becomes the thrust of this paper, to investigate the common trends in mass flash generation during FSP and its commonly employed reduction strategies. Mass flash is caused by high rotational speed at low travel speed and vice versa, flat shoulder, no and low tilt angles, high plunge depth, axial force, and travel force. Mass flash causes material loss, loss of volume fraction control target, material thinning, and leads to poor quality fabrications. Mass flash reduction strategies include the use of high tool tilt angles, concaved tool shoulder, proportional rotational speed and travel speed, and optimal plunge depth, axial force and travel speed as supported by both the experimental and numerical modeling studies. [ABSTRACT FROM AUTHOR]

The aim is to reduce the elastic deformation of the web and side walls of low-stiffness thin-walled beams when the floating fixture method is used. This paper takes the number and position of fixture points as the optimization variables, establishes a calculation model of elastic deformation, and constructs the objective function of maximum total elastic deformation. An optimized solution utilizing the augmented multiplier method is employed, which forms the basis for the fixture layout optimization method to reduce the elastic deformation of low-stiffness thin-walled beams. A theoretical calculation, simulation analysis, and the fixture layout optimization of total maximum elastic deformation were completed using an aluminum alloy low-stiffness thin-walled beam as an example. The results show that based on the optimized layout, the average relative error between the calculated value and the simulated value of total maximum elastic deformation is 17.43%, and the simulated value of maximum elastic deformation is reduced by 48.49% after optimizing the fixture layout. The measured value is reduced by 0.02 mm on average, and deformation is reduced by 74.07%, which verifies the effectiveness of the floating fixture layout optimization control of machining elastic deformation proposed in this paper. [ABSTRACT FROM AUTHOR]

It is difficult for traditional aluminum alloy manufacturing technology to meet the requirements of large-scale and high-precision complex shape structural parts. Wire Arc additive manufacturing technology (WAAM) is an innovative production method that presents the unique advantages of high material utilization, a large degree of design freedom, fast prototyping speed, and low cast. As a result, WAAM is suitable for near-net forming of large-scale complex industrial production and has a wide range of applications in aerospace, automobile manufacturing, and marine engineering fields. In order to serve as a reference for the further development of WAAM technology, this paper provides an overview of the current developments in WAAM both from the digital control system and processing parameters in summary of the recent research progress. This work firstly summarized the principle of simulation layering and path planning and discussed the influence of relative technological parameters, such as current, wire feeding speed, welding speed, shielding gas, and so on. It can be seen that both the welding current and wire feeding speed are directly proportional to the heat input while the travel speed is inversely proportional to the heat input. This process regulation is an important means to improve the quality of deposited parts. This paper then summarized various methods including heat input, alloy composition, and heat treatment. The results showed that in the process of WAAM, it is necessary to control the appropriate heat input to achieve minimum heat accumulation and improve the performance of the deposited parts. To obtain higher mechanical properties (tensile strength has been increased by 28%–45%), aluminum matrix composites by WAAM have proved to be an effective method. The corresponding proper heat treatment can also increase the tensile strength of WAAM Al alloy by 104.3%. In addition, mechanical properties are always assessed to evaluate the quality of deposited parts. The mechanical properties including the tensile strength, yield strength, and hardness of the deposited parts under different processing conditions have been summarized to provide a reference for the quality evaluation of the deposition. Examples of industrial products fabricated by WAAM are also introduced. Finally, the application status of WAAM aluminum alloy is summarized and the corresponding future research direction is prospected. [ABSTRACT FROM AUTHOR]

In Sweden, steel bridges are the most common solution regarding prefabricated short-span (15-35 m) pedestrian bridges. The most common bridge type for this application is a carbon steel truss bridge with an orthotropic deck consisting of a 10-12 mm deck plate and trapezoidal stiffeners. For these bridges, the deck is the main driver regarding economic and environmental costs, originating from, e.g., high material consumption and maintenance activities. This paper aims to compare the economic aspects between a conventional steel deck and an extruded aluminum deck from an investment cost perspective. The aluminum deck is homogenous, i.e., containing no mechanical connections. To perform this case study, an optimization routine is developed and executed for the aluminum alternative. This optimization study targets the minimum weight and is constrained by the Eurocode design code. A sub-model approach is adopted for the numerical analysis, based on shell and solid elements. The procedure to go from a cross-section defined by a set of parameters to reach the optimized bridge deck is presented. The studies that are reported in this paper show that the developed optimization routine gives satisfactory results. Furthermore, they indicate that homogenous extruded aluminum decks can be a viable deck option for pedestrian bridges. [ABSTRACT FROM AUTHOR]

Marine gas-water separator is mainly used to filter impurities in the air for gas turbine, and it also needs to have certain anti-impact ability in engineering application. In order to study its impact resistance, this paper used the method of combination of simulation and experiment. Firstly, the material properties of 5083 aluminium alloy were determined. On the basis of this, the drop test under different acceleration was carried out. Then ABAQUS software was used to carry on the drop simulation analysis and antiknock simulation analysis. The feasibility of the simulation method was verified by comparison of simulation results and experimental results. The following conclusions are obtained: the impact of 5 g-33 g drop will not affect the operation of the gas-water separator; the impact of guide vane's transverse fall on the gas-water separator is less than that of guide vane's longitudinal fall; the direction with guide vane's support has stronger anti-detonating performance than that without guide vane's support. The conclusions drawn in this paper can be used for specific optimization and protection in practical use, and provide a certain reference for the impact performance field of Marine gas-water separator. [ABSTRACT FROM AUTHOR]

At room temperature, Al alloys have excellent mechanical properties and are widely used in automotive, electronics, aerospace and other fields, but it is difficult to maintain this advantage in the middle and high temperature ranges. To address this issue, second-phase Al11RE3 (RE represents rare earth element) was introduced into a Al-Mg-RE alloy as its primary constituent. By incorporating RE elements as additives, this material exhibits exceptional mechanical and thermal properties at elevated temperatures. Based on first principles and quasi-harmonic approximation (QHA), the nucleation growth mechanism and surface properties of second-phase Al11RE3 were studied in this paper. The interfacial energy γ α / β , strain energy Δ E CS and chemical driving force Δ G V of Al11RE3 were obtained. Models1, 4, and 6 have better properties of para-site connections than inter-site connections. It is found that the resistances of particle nucleation, interface energy γ α / β and strain energy Δ E CS , first increase and then decrease with increased atomic number REs, but they are much smaller than the chemical driving force Δ G V . A reduced chemical driving force and a diminished nucleation radius R* are more favorable for the process of nucleation. The addition of Sc is the most unfavorable for nucleation, and La has the strongest nucleating ability, which gradually decreases as the atomic number of the lanthanide element increases. The nucleation ability of the Al11RE3 phase decreases with increasing temperature, which is consistent with the experiments. The nucleation radius R* also increases with increasing temperature, indicating that the nucleation ability decreases as the atomic number of the lanthanide elements increases. Since the smaller the nucleation radius R* the easier the nucleation, compared with model4 and 6, model1 has a smaller nucleation radius R* and the smallest increment. Thus, model1 is more prominent in the nucleation mechanism. In the particle growth study, the smaller the diffusion activation energy Q, the faster the diffusion rate in the Al matrix, and hence the higher the coiling rate, which promotes the growth of second-phase particles. The diffusion activation energy Q decreases sequentially from La to Ce and then increases with atomic number. The coarsening rate K LSW of the Al11RE3 phase in models1, 4, and 6 increased with increasing temperature, which promoted the growth of particles. This paper is intended to provide a solid theoretical basis for the production and application of aluminum alloy at high temperatures. [ABSTRACT FROM AUTHOR]

The aircraft wing is a critical component that enables flight and enhances safety and stability. Its design and function are critical considerations in the overall performance and safety of an aircraft. This paper aims to focus on the design of the aircraft wing structure for its importance. SolidWorks-2018 program was used to model the system of the wing parts, which consists of seven ribs and two spars and airfoil NACA 0012 was used and aluminum alloy T7075 as a material for the structure of the aircraft wing and its surface. The generated loads were projected on it obtained using the Vortex Lattice method when dividing it into (8, 16 and 24) panels to extract the amount of stress, strain and deformation to which the wing is exposed. The analyses conducted on the proposed wing showed that the wing structure is acceptable in design because of its lightweight, weighing approximately 5556.98 grams, and safe, as the stress resulting from the numerical analysis under the influence of the aerodynamic force is less than the yield strength of the structural material. [ABSTRACT FROM AUTHOR]

As the construction industry places increasing emphasis on environmental conservation and sustainability, this trend has spurred profound research into the optimization of door and window performance. One of the critical components of windows is their frames. Over the past several decades, the design of window frames has undergone significant innovations, ranging from introducing new materials to novel design concepts. The performance of window frames is typically influenced by materials, structural design, and the surrounding environment. Consequently, this paper analyzes the common window frame materials in Chinese civil buildings through investigation. It explores commonly used types of window frames available in the market, focusing on their materials and structural designs. It analyzes issues observed during their usage, integrates findings from existing research, and discusses the performance of window frame materials. Additionally, it explores improvement strategies to meet the evolving demands of contemporary and future architectural doors and windows, providing valuable reference points for designers. Finally, approaching the discussion from a sustainable development perspective, the paper evaluates the environmental impact of wood, aluminum alloy, polymer, and composite window frame materials. It emphasizes that wood- and aluminum-clad wood windows represent sustainable options with versatile applications in diverse scenarios. [ABSTRACT FROM AUTHOR]

Due to their homogeneity and excellent ratio between load capacity and weight, thinwalled aluminum structures are used as structural parts in the aerospace, automotive and military industries. The manufacture of these thin-walled structures is mainly done by removing a large amount of material from full raw pieces, sometimes up to 95% of their initial mass. Because of a large volume of material removing, it is necessary to achieve high productivity, which is limited by the lack of rigidity of the thin walls of these structures. As a result, errors occur, while reducing accuracy and machining quality. The main subject and objective of this paper is related to the optimization of high-speed machining parameters of linear thin-walled structures made of aluminum alloy Al7075 from the aspect of surface quality of processed superficial as a goal function. For this purpose, experiments were carried out based on which conclusions were made of the influence of input parameters on the surface roughness. [ABSTRACT FROM AUTHOR]

This paper forms part of an ongoing investigation into the tools required in linear elastic fracture mechanics (LEFM) for evaluating the durability of components designed for limited life replacement. In this study, we demonstrate that the USAF 'Characteristic K' method, when combined with the Hartman–Schijve adaptation of the NASGRO crack growth formula, can predict the impact of underloads on the propagation of small cracks in aluminum alloy AA7050-T7451 with reasonable accuracy. The published da/dN versus ΔK small crack growth curves associated with five specific underload spectra are examined. It is found that, in each case, there is reasonably good agreement between the predicted and the measured curves. To the best of the author's knowledge, this paper is the first to highlight the ability of the USAF Characteristic K approach, when coupled with the Hartman–Schijve equation, to reasonably accurately predict the growth of small cracks subjected to a range of underload spectra. [ABSTRACT FROM AUTHOR]

Marine structures are constantly exposed to the corrosive effects of seawater, making effective corrosion protection crucial for their longevity and performance. Sacrificial anodes, commonly made of zinc, aluminum, or magnesium alloys, are widely employed to mitigate corrosion by sacrificing themselves to protect the steel structures. However, the selection and implementation of sacrificial anode materials present various challenges that need to be addressed. This paper explores the challenges associated with sacrificial anode materials for steel structures and provides potential solutions. To overcome these challenges, the paper proposes solutions such as using advanced alloy compositions, protective coatings, hybrid anode systems, and improved design considerations. Furthermore, the importance of monitoring techniques to assess the performance and remaining lifespan of sacrificial anodes is emphasized. Several case studies and experimental findings are discussed to illustrate the effectiveness and limitations of sacrificial anode materials based on zinc alloys, aluminum alloys, and magnesium alloys. The paper highlights the need for ongoing research and development efforts to address the evolving demands of corrosion protection in marine environments. [ABSTRACT FROM AUTHOR]

Strategies for obtaining deep slots in soft materials can vary significantly. Conventionally, the tool travels along the slot, removing material mainly with the side cutting edges. However, a "plunge milling" strategy is also possible, performing the cut vertically, taking advantage of the tip cutting edges that almost reach the center of the tool. Although both strategies are already commonly used, there is a clear gap in the literature in studies that compare tool wear, surface roughness, and productivity in each case. This paper describes an experimental study comparing the milling of deep slots in AA7050-T7451 aluminum alloy, coated with a novel DLCSiO500W3.5O2 layer to minimize the aluminum adhesion to the tool, using conventional and plunge milling strategies. The main novelty of this paper is to present a broad study regarding different factors involved in machining operations and comparing two distinct strategies using a novel tool coating in the milling of aeronautical aluminum alloy. Tool wear is correlated with the vibrations of the tools in each situation, the cycle time is compared between the cases studied, and the surface roughness of the machined surfaces is analyzed. This study concludes that the cycle time of plunge milling can be about 20% less than that of conventional milling procedures, favoring economic sustainability and modifying the wear observed on the tools. Plunge milling can increase productivity, does not increase tool tip wear, and avoids damaging the side edges of the tool, which can eventually be used for final finishing operations. Therefore, it can be said that the plunge milling strategy improves economic and environmental sustainability as it uses all the cutting edges of the tools in a more balanced way, with less global wear. [ABSTRACT FROM AUTHOR]

Featured Application: The paper demonstrates key structural characteristics of a novel aluminum alloy conceived for AM-based components in the aviation frame. The recent advances achieved in additive manufacturing (AM) technology demonstrate the potential to realize customized metal components, ensuring weight reduction opportunities. These benefits make AM attractive for high-cost aerospace applications, especially where high geometric complexity is required. In the context of an EU research scenario, the H2020 MANUELA (Additive Manufacturing Using Metal Pilot Line) project promotes the development of new technologies for design optimization by enabling the application of novel materials in AM. This paper illustrates recent advances in a new aluminum alloy (Al-HS1) with high strength emphasizing all of the characterization steps at the coupon level. This material has been employed in the re-engineering of a conventional hydraulic manifold using a powder bed fusion-laser beam (PBF-LB) process. Both the simulations and structural tests allowed for proving its compliance and technological maturity with industrial standards and applicable airworthiness requirements. [ABSTRACT FROM AUTHOR]

This paper presents the results of an extensive investigation into the durability of cold spray repairs to corrosion damage in AA7075-T7351 aluminium alloy specimens where, prior to powder deposition, the surface preparation involved grit blasting. In this context, it is shown that the growth of small naturally occurring cracks in cold spray repairs to simulated corrosion damage can be accurately computed using the Hartman–Schijve crack growth equation in a fashion that is consistent with the requirements delineated in USAF Structures Bulletin EZ-SB-19-01, MIL-STD-1530D, and the US Joint Services Structural Guidelines JSSG2006. The relatively large variation in the da/dN versus ΔK curves associated with low values of da/dN highlights the fact that, before any durability assessment of a cold spray repair to an operational airframe is attempted, it is first necessary to perform a sufficient number of tests so that the worst-case small crack growth curve needed to perform the mandated airworthiness certification analysis can be determined. [ABSTRACT FROM AUTHOR]

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Purpose: To investigate the changes in corrosion behaviour of severely deformed by accumulative roll bonding aluminium alloy AA1050. Design/methodology/approach: To determine the influence of the accumulative roll bonding on microstructure, texture, and grain size, electron backscattered diffraction was used. Corrosion behaviour was evaluated in a 3.5 wt.% sodium chloride water solution using anodic polarisation. Findings: It was found out that accumulative roll bonding up to eight cycles led to an increase in corrosion rate compared to annealed alloy, but the increase in the number of cycles of accumulative roll bonding from two to eight shows a tendency toward lowering corrosion rates. It has a beneficial influence on pitting corrosion susceptibility. Research limitations/implications: The presented research focuses only on the influence of texture and grain size on severely deformed aluminium alloy AA1050 corrosion. Other factors, such as accumulated during deformation stresses, could also play their role in the corrosion process. Originality/value: The paper reports results on the influence of two factors - texture and grain size, on the corrosion of severely deformed aluminium alloy AA1050. Most reports on the topic include only the influence of texture or grain size. [ABSTRACT FROM AUTHOR]

This work is part of the European RFCS "FISHWALL" project entitled "Fire and Seismic performances of hybrid fire walls in case of single‐storey industrial and commercial steel buildings". The aim of the project is to design a hybrid firewall solution using sandwich panels for single‐storey buildings connected with the unprotected steel structure by means of fusible links, made of aluminium bolts. In this respect, the paper shows the results of preliminary numerical analyses performed on existing case studies of single‐storey steel buildings located in low and moderate seismicity zones and they were used: i) to estimate the seismic forces acting on the fusible links and ii) to subsequently design the specimens to be tested in the laboratory. In this respect, several finite elements models were developed in order to consider the widest range of configurations of the firewall with respect to the direction of the portal frame composing the steel buildings, i.e. firewall parallel and orthogonal to the portal frames. Based on the estimated forces, the design of the six different specimens was performed and it is thoroughly shown in the paper. [ABSTRACT FROM AUTHOR]

This document is a compilation of various research papers and articles that discuss the use of machine learning and other techniques to predict fatigue lifetimes in different materials and structures. The papers cover topics such as the use of neural networks, XGBoost, and physics-informed machine learning models for fatigue prediction. The research focuses on different materials, including aluminum alloys and lead-free solders, and explores the effects of factors such as wear, lubrication, corrosion, and stress on fatigue life. The papers provide insights into the application of machine learning techniques in predicting fatigue lifetime and offer potential solutions for improving the accuracy of these predictions. [Extracted from the article]

This article provides an overview of laser surface engineering in the field of tribology, which focuses on friction, wear, and lubrication between surfaces in motion. It introduces a special issue on laser surface engineering for tribology, which includes thirteen papers covering topics such as laser cladding, surface texturing, and additive manufacturing. Each paper explores different aspects of laser surface engineering and offers insights for future research and development in the field. The article discusses various research contributions, including the impact of preheating temperatures on laser-clad coatings, the use of laser-assisted surface texturing to reduce friction and wear, and the proposal of a nitride layer to resist tribocorrosion. The findings contribute to improving the wear and corrosion resistance of materials through laser surface engineering. The article concludes by suggesting future research directions and emphasizing the importance of tailoring laser surface engineering approaches to meet industry-specific requirements. [Extracted from the article]

The friction/adhesion between the tool and chip is generally large in metal cutting, and it causes many problems such as high cutting energy/rough surface finish. To suppress this, cutting fluid and tool coating are used in practice, but they are high in energy/cost and environmentally unfriendly. Therefore, this paper investigates the extraordinarily high-speed cutting (EHS cutting) mechanics of mainly soft and highly heat-conductive materials and proposes their application to solve the friction/adhesion problem in an environmentally friendly manner. In order to clarify the EHS cutting mechanics, a simple analytical model is constructed and experiments are conducted with measurement of the cutting temperature and forces. As a result, the following points are clarified/found: (1) heat softening at the secondary plastic deformation zone rather than the primary plastic deformation zone, (2) friction coefficient drop to 0.170 in EHS cutting, and (3) gradually increasing trend of cutting temperature in EHS cutting. Finally, EHS cutting is applied to dry cutting of aluminum alloys with a non-coated carbide tool and compared to conventional wet cutting with a DLC-coated carbide tool, and it is shown that a coating/coolant can be omitted in this region to achieve environmentally friendly cutting. [ABSTRACT FROM AUTHOR]

In recent years, there has been a lack of information in the literature regarding the extrusion and connection of closed profiles from oxygen-free copper in bridge dies. Available studies contain information on the processes of extrusion and connection of profiles from aluminium alloys and various types of steel. However, there is a lack of detailed data on the values of technological parameters for which copper is joined in the extrusion process. Therefore, one of the goals of this work is to fill the gap in the literature regarding the extrusion of oxygen-free copper in bridge dies. In this work, the authors determined the thermo-mechanical conditions at which oxygen-free copper will be joined. This paper describes the effects of charge temperature and hydrostatic pressure in the weld zone of a bridge die on copper bonding in the fabrication of tubular profiles. Physical tests of the welding process under the conditions of upsetting a material consisting of two parts were carried out using the Gleeble 3800 metallurgical process simulator with the PocketJaw module in the standard configuration for SICO (strain-induced crack opening) tests. For the numerical simulations, the commercial computer programme FORGE®NxT 2.1. using the finite element method (FEM) was used. Based on the analysis of the test results obtained, it was found that complete material bonding during the extrusion process could be achieved for a charge temperature higher than 600 °C and a hydrostatic pressure of 45–65 MPa. [ABSTRACT FROM AUTHOR]

Manufacturing of bent composite tubes with variable cross-section is a challenge. The traditional process in composite materials uses retractable mandrels that in case of inflated or bent tubes cannot be applied. The tubular composite elements are often used in high performance bicycles, in the manufacturing of frames, handlebars, saddle pipe supports, etc. This paper presents research on the design of a Mountain Bike (MTB) riser handlebar made of Fiber Reinforced Polymer (FRP). The handlebar is numerically analyzed to estimate the most suitable stacking sequence of Carbon Fiber Reinforced Polymer (CFRP) layers. Depending on the safety standard of bicycle handlebars, a case of longitudinal bending tests was numerically evaluated. Comparing the weight of the CFRP handlebar with the steel handlebar of the same shape, the mass reduction is 5.2 times. The obtained results indicate a two-fold reduction in the weight of the handlebar if it is compared to a handlebar made of aluminum alloys. The research also presents the manufacturing process of the composite mold, and CFRP tubular element. Prepreg CFRP materials are used to manufacture the handlebar, the employed technology being the vacuum bag forming and autoclave curing process. [ABSTRACT FROM AUTHOR]

This paper employed squeeze-casting (SC) technology to develop a novel Al-7Si-1.5Cu-1.2Ni-0.4Mg-0.3Mn-0.15Ti heat-resistant alloy, addressing the issue of low room/high temperature elongation in traditional gravity casting (GC). Initially, the effects of SC and GC processes on the microstructure and properties of the alloy were investigated, followed by an examination of the evolution of the microstructure and properties of the SC samples over thermal exposure time. The results indicate that the SC process significantly improves the alloy's microstructure. Compared to the GC alloy, the secondary dendrite arm spacing of the as-cast SC alloy is refined from 50.5 μm to 18.5 μm. Meanwhile, the size and roundness of the eutectic Si phase in the T6-treated SC alloy are optimized from 11.7 μm and 0.75 μm to 9.5 μm and 0.85 μm, respectively, and casting defects such as porosity are reduced. Consequently, the ultimate tensile strengths (UTSs) at room temperature and at 250 °C of the SC alloy are 5% and 4.9% higher than that of GC alloy, respectively, and its elongation at both temperatures shows significant improvement. After thermal exposure at 250 °C for 120 h, the morphology of the residual second phase at the grain boundaries in the SC alloy becomes more rounded, but the eutectic Si and nano-precipitates undergo significant coarsening, resulting in a 49% decrease in UTS. [ABSTRACT FROM AUTHOR]