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The article announces several awards for 14th Foseco Cup Excellent Foundry Papers of 2011 including the gold award to authors Jin Yongxi and Zhang Jinshan and silver award to author Xi Jie for their papers.

The electroslag remelting (ESR) process is widely used to produce high-quality ingots and billets for high-alloyed steels and alloys. Both the single-phase and three-phase alternating current diagram with bifilar and monofilar connection are in use for heavy ingot manufacturing. The numerical simulation of the three-phase bifilar circuit for the 120 t three-phase bifilar six-electrode ESR furnace at different variants of electric connection was presented and discussed. At the bifilar diagram of power supply, the geometrical location of electrodes in a mould holds critical importance for performances: the close location of bifilar pair electrodes provides the highest heat productivity, but the equidistant location of electrodes gives a much more uniform heat distribution. The monofilar mulit-electrode diagram of three-phase connection without phase shift shows the most uniform distribution of potential and heat generation as well as a favorable magnetic field that makes this kind the most promising for providing a high quality of heavy ingots. [ABSTRACT FROM AUTHOR]

Metal additive manufacturing (MAM) technology has experienced rapid development in recent years. As both equipment and materials progress towards increased maturity and commercialization, material metallurgy technology based on high energy sources has become a key factor influencing the future development of MAM. The calculation of phase diagrams (CALPHAD) is an essential method and tool for constructing multi-component phase diagrams by employing experimental phase diagrams and Gibbs free energy models of simple systems. By combining with the element mobility data and non-equilibrium phase transition model, it has been widely used in the analysis of traditional metal materials. The development of CALPHAD application technology for MAM is focused on the compositional design of printable materials, the reduction of metallurgical imperfections, and the control of microstructural attributes. This endeavor carries considerable theoretical and practical significance. This paper summarizes the important achievements of CALPHAD in additive manufacturing (AM) technology in recent years, including material design, process parameter optimization, microstructure evolution simulation, and properties prediction. Finally, the limitations of applying CALPHAD technology to MAM technology are discussed, along with prospective research directions. [ABSTRACT FROM AUTHOR]

The intelligent detection technology driven by X-ray images and deep learning represents the forefront of advanced techniques and development trends in flaw detection and automated evaluation of light alloy castings. However, the efficacy of deep learning models hinges upon a substantial abundance of flaw samples. The existing research on X-ray image augmentation for flaw detection suffers from shortcomings such as poor diversity of flaw samples and low reliability of quality evaluation. To this end, a novel approach was put forward, which involves the creation of the Interpolation-Deep Convolutional Generative Adversarial Network (I-DCGAN) for flaw detection image generation and a comprehensive evaluation algorithm named TOPSIS-IFP. I-DCGAN enables the generation of high-resolution, diverse simulated images with multiple appearances, achieving an improvement in sample diversity and quality while maintaining a relatively lower computational complexity. TOPSIS-IFP facilitates multi-dimensional quality evaluation, including aspects such as diversity, authenticity, image distribution difference, and image distortion degree. The results indicate that the X-ray radiographic images of magnesium and aluminum alloy castings achieve optimal performance when trained up to the 800th and 600th epochs, respectively. The TOPSIS-IFP value reaches 78.7% and 73.8% similarity to the ideal solution, respectively. Compared to single index evaluation, the TOPSIS-IFP algorithm achieves higher-quality simulated images at the optimal training epoch. This approach successfully mitigates the issue of unreliable quality associated with single index evaluation. The image generation and comprehensive quality evaluation method developed in this paper provides a novel approach for image augmentation in flaw recognition, holding significant importance for enhancing the robustness of subsequent flaw recognition networks. [ABSTRACT FROM AUTHOR]

Additive manufacturing technology is highly regarded due to its advantages, such as high precision and the ability to address complex geometric challenges. However, the development of additive manufacturing process is constrained by issues like unclear fundamental principles, complex experimental cycles, and high costs. Machine learning, as a novel artificial intelligence technology, has the potential to deeply engage in the development of additive manufacturing process, assisting engineers in learning and developing new techniques. This paper provides a comprehensive overview of the research and applications of machine learning in the field of additive manufacturing, particularly in model design and process development. Firstly, it introduces the background and significance of machine learning-assisted design in additive manufacturing process. It then further delves into the application of machine learning in additive manufacturing, focusing on model design and process guidance. Finally, it concludes by summarizing and forecasting the development trends of machine learning technology in the field of additive manufacturing. [ABSTRACT FROM AUTHOR]

Up to one million metric tonnes of coal are crushed each year. The crushed coal continually flows through a pipe delivery system at a rate of up to 60 tonnes per hour. In a nitrogen rich environment, the delivery system is constantly under pressure of nearly 9 bar. Filters are used in each pipe delivery system to prevent incorrectly sized material and 'foreign materials' from entering the blast furnace. Any incorrect material is held up long enough to be broken-down before becoming small enough to pass through the filter. In the past, foreign materials simply blocked the system. The aforementioned environment creates materials' applications issues. This paper describes how ADI is used to meet these challenging demands in a crushed coal delivery and filtering system. The work described in this paper has resulted in a number of new applications using ADI and CADI materials which are now operating in 'waste to energy incineration' plants, aluminum production plants, iron sinter and iron slag processing application, such as rotary crusher, cage crusher, curved door, etc. [ABSTRACT FROM AUTHOR]

Squeeze casting is a well-established and reliable process for fabricating high-integrity metallic alloys, bimetals, and composites. The quality and high performance of squeeze cast components are dependent on optimum casting conditions. Inappropriate selection of parameter values may adversely affect the quality of the casting. The squeeze cast components are generally subjected to secondary processing such as heat treatment, extrusion, and other bulk deformation processes to improve the microstructural features and mechanical properties. Heat treatment further refines the grains and reduces porosity, consequently improving tensile strength, and hardness; however, ductility decreases. This paper provides a comprehensive review on studies concerning the influence of processing parameters on porosity, density, percentage elongation, strength, hardness, wear, and fracture of squeeze casting alloys, aiming to provide sufficient information on the squeeze casting process and the effects of processing parameters on product quality. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC), a group IV compound and wide-bandgap semiconductor for high-power, high-frequency and high-temperature devices, demonstrates excellent inherent properties for power devices and specialized high-end markets. Solution growth is thermodynamically favorable for producing SiC single crystal ingots with ultra-low dislocation density as the crystallization is driven by the supersaturation of carbon dissolved in Si-metal solvents. Meanwhile, solution growth is conducive to the growth of both N- and P-type SiC, with doping concentrations ranging from 1014 to 1019 cm-3. To date, 4-inch 4H-SiC substrates with a thickness of 15 mm produced by solution growth have been unveiled, while substrates of 6 inches and above are still under development. Based on top-seeded solution growth (TSSG), several growth techniques have been developed including solution growth on a concave surface (SGCS), melt-back, accelerated crucible rotation technique (ACRT), two-step growth, and facet growth. Multi-parameters of the solution growth including meniscus, solvent design, flow control, dislocation conversion, facet growth, and structures of graphite components make high-quality single crystal growth possible. In this paper, the solution growth techniques and corresponding parameters involved in SiC bulk growth were reviewed. [ABSTRACT FROM AUTHOR]

The paper reviews original data obtained by the present authors, revealed in recent separate publications, describing specific procedures for high quality grey irons, and reflecting the forecast needs of the worldwide iron foundry industry. High power, medium frequency coreless induction furnaces are commonly used in electric melting grey iron foundries. This has resulted in low sulphur (<0.05wt.%) and aluminium (<0.005wt.%) contents in the iron, with a potential for higher superheating (>1,500 °C), contributing to unfavourable conditions for graphite nucleation. Thin wall castings are increasingly produced by these electric melt shops with a risk of greater eutectic undercooling during solidification. The paper focused on two groups of grey cast irons and their specific problems: carbides and graphite morphology control in lower carbon equivalent high strength irons (CE=3.4%-3.8%), and austenite dendrite promotion in eutectic and slightly hypereutectic irons (CE=4.1%-4.5%), in order to increase their strength characteristics. There are 3 stages and 3 steps involving graphite formation, iron chemistry and iron processing that appear to be important. The concept in the present paper sustains a threestage model for nucleating flake graphite [(Mn,×)s type nuclei]. There are three important groups of elements (deoxidizer, Mn/S, and inoculant) and three technological stages in electric melting of iron (superheat, pre-conditioning of base iron, final inoculation). Attention is drawn to a control factor (%Mn) x× (%s) ensuring it equals to 0.03 - 0.06, accompanied by 0.005wt.%-0.010wt.% Al and/or Zr content in inoculated irons. It was found that iron powder addition promotes austenite dendrite formation in eutectic and slightly eutectic, acting as reinforcement for the eutectic cells. But, there is an accompanying possible negative influence on the characteristics of the (Mn,×)S type graphite nuclei (change the morphology of nuclei from polygonal compact to irregular polygonal, and therefore promote chill tendency in treated irons). A double addition (iron powder + inoculant) appears to be an effective treatment to benefit both austenite and graphite nucleation, with positive effects on the final structure and chill tendency. [ABSTRACT FROM AUTHOR]

The first part of the paper summarizes the performance of two mould devices, illustrating by representative shrinkage tendency results in ductile cast iron as affected by mould rigidity (green and furan resin sand moulds) and inoculant type (FeSibased alloys). Less rigid green sand moulds encourage the formation of contraction defects, not only because of the high initial expansion values (εdi)max, but also because of the increased solidification undercooling. A high inoculation efficiency means not only lowering the carbides formation sensitivity and increasing the nodule count, but also a prolonged graphitization through to the end of the eutectic freezing, as observed by the high population of small late forming nodules, which leads to minimizing the tendency for shrinkage. The second part of the paper illustrates an application of this equipment to commercial foundry use. It conducts thermal analysis and volume change measurements in a single ceramic cup with cast iron quality as a variable. La-bearing FeSi inoculant appears to be more effective than RE (Rare Earth) -FeSi alloy in FeSiMgCa treated irons (no RE), in terms of reducing eutectic undercooling and (εdi)max, favourable for lower sensitivity to shrinkage formation. Experiments also compared solidification patterns for white [WI], grey [GI] and ductile [DI] irons, to correlate the most important events between the cooling curves and contraction curves, to evaluate the sensitivity to shrinkage formation. All of the irons have similar values for initial expansion up to the start of eutectic freezing, but, after that, the graphite formation promotes expansion (more than 5 times for nodular graphite), resulting in a difference in maximum expansion (2 times higher for DI). The graphitic expansion has two contrary effects. Increased graphitic expansion (force) leads to a higher shrinkage sensitivity during the first part of the eutectic reaction, but also to a decrease of shrinkage at the end of solidification, due to forcing the last liquid iron to occupy the previous formed cavities. Consequently, strong graphitization process promotion at the end of solidification favours the castings' soundness. [ABSTRACT FROM AUTHOR]

The heterogeneous nucleation process of NH4Cl crystals from a NH4Cl-70wt.%H2O solution on rough chilling substrates was considered in this paper. Scratched and etched substrates of aluminum were prepared with different surface morphologies. It was concluded that for nucleation to occur on a rough substrate surface, the wettability or the generally said roughness are not the key factors affecting the heterogeneous nucleation process. Rather the surface morphologies on the nanometer scale, which is close to the scale of the critical nucleation radius, are more important. [ABSTRACT FROM AUTHOR]

Two important factors affecting the performance of sand mold/core generated by 3D printing (3DP) are strength and dimensional accuracy, which are not only closely related to the reactivity of furan resin and the phase transition of silica sand, but also the curing agent system of furan resin. This paper studies the influence of gel time on the strength and dimensional accuracy of a 3DP sand mold/core, taking the furan resin system as an example and using a sand specimen generated by a 3DP inkjet molding machine. The experiment demonstrates that the gel time of 3 to 6 min for the sand mixture suits 3DP core-making most under the experimental condition. However, it should be noted that under the same resin condition, the strength of a no-bake sand mold/core is higher than that of a 3DP sand mold/core. The dimensional accuracy of the sand mold/core does not change significantly when the gel time is less than 15 min. Improving the activity of binder and developing ultra-strong acid with low corrosion shall be an effective way to improve the quality of the mold/core by 3D printing. [ABSTRACT FROM AUTHOR]

With the advent of Industry 4.0, more and more investment casting enterprises are implementing production manufacturing systems, especially in the last two years. This paper summarizes three new common requirements of the digital management aspect in precision casting enterprises, and puts forward three corresponding techniques. They are: the production process tracking card technology based on the main-sub card mode; the workshop site production process processing technology based on the barcode; and the equipment data integration technology. Then, this paper discusses in detail the principle, application and effect of these technologies; to provide the reference for enterprises to move towards digital casting and intelligent casting. [ABSTRACT FROM AUTHOR]

Selective laser melting (SLM) has been widely used in the fields of aviation, aerospace and die manufacturing due to its ability to produce metal components with arbitrarily complex shapes. However, the instability of SLM process often leads to quality fluctuation of the formed component, which hinders the further development and application of SLM. In situ quality control during SLM process is an effective solution to the quality fluctuation of formed components. However, the basic premise of feedback control during SLM process is the rapid and accurate diagnosis of the quality. Therefore, an in situ monitoring method of SLM process, which provides quality diagnosis information for feedback control, became one of the research hotspots in this field in recent years. In this paper, the research progress of in situ monitoring during SLM process based on images is reviewed. Firstly, the significance of in situ monitoring during SLM process is analyzed. Then, the image information source of SLM process, the image acquisition systems for different detection objects (the molten pool region, the scanned layer and the powder spread layer) and the methods of the image information analysis, detection and recognition are reviewed and analyzed. Through review and analysis, it is found that the existing image analysis and detection methods during SLM process are mainly based on traditional image processing methods combined with traditional machine learning models. Finally, the main development direction of in situ monitoring during SLM process is proposed by combining with the frontier technology of image-based computer vision. [ABSTRACT FROM AUTHOR]

The application of additive manufacturing technology is one of the main approaches to achieving the rapid casting. Additive manufacturing technology can directly prepare casting molds (cores) with no need of patterns, and quickly cast complex castings. The combination of additive manufacturing and traditional casting technology can break the constraint of traditional casting technology, improve casting flexibility, and ameliorate the working environment. Besides, additive manufacturing promotes the realization of "free casting", greatly simplifying the processing procedures and shortening the manufacturing cycle. This paper summarizes the basic principle of additive manufacturing technology and its development situation domestically and overseas, mainly focusing on the development status of several main additive manufacturing technologies applicable to the foundry field, including three-dimensional printing, selective laser sintering, stereolithography, layered extrusion forming, etc. Finally, the future development trend of additive manufacturing technology in the foundry field is prospected. [ABSTRACT FROM AUTHOR]

The coolant pump impeller casting is the only rotating component in the nuclear island of an AP1000 nuclear power station, and is required to have a 60- year service time, which requires advanced materials and processing technologies to guarantee. In this paper, the casting process was studied, designed and modified by means of numerical simulation. The gating system was distributed symmetrically and the runner diameter was a little bigger for avoiding sand wash and turbulence; the feeding system focused on the solution of blades feeding, as some parts of which should reach Severity Level 1 radioactive testing standard. Therefore, upper and lower plates cooperating with chillers acted as feeding method besides additional 2-3 times thickness; in addition, lowering sand core strength, decreasing pouring temperature and increasing dimension allowance would be adopted to avoid crack defects. Finally, the pilot impeller was cast. The results show that the casting process design is reasonable, as the liquid rises very smoothly when pouring, and no volume defects are found by means of 100% radioactive testing. Based on this casting process, 16 coolant pump impellers have been successfully produced and delivered to customers. [ABSTRACT FROM AUTHOR]

Since its first literature mention in conjunction with cast iron in 1931 by Esser and Lautenbusch, thermal analysis (TA) has journeyed a long way. Today it is an accepted and widely used tool for process control for all types of cast irons. This paper reviews the latest progress in the development of equipment and analysis methods that make TA successful in applications such as the estimation of chemical composition, graphitization potential, and the shape and number of graphite aggregates. The potential and limitations of the prediction of shrinkage defects propensity are analyzed in some details. Examples of attempts at prediction of mechanical properties and shrinkage propensity are also discussed. Several graphs showing the data scattering are presented to convey the reader a better sense of the accuracy of various predictions. [ABSTRACT FROM AUTHOR]

This paper gives a brief introduction to the four research methods for the study on thermal conductivity of cast irons, including experimental measurement, statistical analysis, effective medium theory and numerical simulation. Recent studies on the thermal conductivity of various cast irons are reviewed through the influence of alloying elements, structural constituents, and temperature. The addition of alloying elements is the main reason that restricts the thermal conductivity of cast irons, especially spheroidal graphite cast iron. The connectivity of graphite has a significant effect on the thermal conductivity of flake and compacted graphite cast irons, semiquantitative and quantitative analysis of this factor is a key and difficult point in the study of thermal conductivity of cast irons. The thermal conductivities of different types of cast irons show varying degrees of dependence on temperature. This phenomenon is the combination of graphite and matrix, rather than just depending on graphite morphology. The study of the relationship between individual phase and temperature is the focus of future research. These summaries and discussions may provide reference and guidance for the future research and development of high thermal conductivity cast irons. [ABSTRACT FROM AUTHOR]

Volume change related defects formation mechanisms are an important detracting phenomenon in production of complex shaped cast components. Among different technical alloys, cast iron behaves in a complex manner due to the combined volume change of the formed phases. The liquid and the austenitic phase are contracting while the graphite phase is expanding during the solidification. The complex volume change in combination with complex casting shapes causes a considerable deviation from isotropy in the solidification domain. The mentioned difficulties are considered the main reason why an extensive research work is condensed in the literature within this topic. The multitude of reported experimental set up and the various efforts to interpret the volume change phenomena in terms of density and thermal expansion coefficients makes the results difficult to compare from different sources. With these difficulties in mind, the present paper presents a broad experimental series and measures unidirectional linear deformation of an industrially spread lamellar cast iron alloy system (Fe-C-2Si) using the push-rod based dilatometer technique. The measurements are divided into two major groups with respect to the liquid iron deformation over the liquidus temperature line, and the austenite deformation below the solidus temperature line. The obtained results are interpreted as thermal expansion coefficients, density variation slopes, and density data at the liquids and solidus temperature. The obtained results are compared with literature data and with calculated values by the Thermo Calc software. [ABSTRACT FROM AUTHOR]

The properties of gray cast iron (GCI) are affected by density of matrix, size of flake graphite and primary austenite. In this paper, the Y-type specimen of GCI was prepared by lost foam casting (LFC) with and without vibration, and the influence of vibration frequency on the density of matrix, size of primary phase, and properties of the GCI was studied. The results show that the length of the flake graphite and the size of the primary austenite in GCI firstly decrease and then increase with the increase of the vibration frequency. With a vibration frequency of 35 Hz, the length of the flake graphite is the shortest, the primary austenite is the finest and the density of the matrix is the highest. In addition, the tensile strength, elongation and hardness of the GCI firstly increase and then decrease with the increase of the vibration frequency, due to the refinement of the primary phase and the increase of the matrix density. In order to analyze the refinement mechanism of the primary phase of the GCI fabricated by the LFC with vibration, the solidification temperature fields of the GCI fabricated by the LFC with the vibration frequency of 0 and 35 Hz were measured. The results show that the vibration reduces the eutectic point of the GCI and increases the supercooling degree during the eutectic transformation. As a result, the length of the flake graphite and the size of the primary austenite in GCI fabricated by LFC with the vibration frequency of 35 Hz decrease. [ABSTRACT FROM AUTHOR]

This paper summarizes melting methods of titanium and titanium alloy, such as vacuum arc melting (VAR) and electron beam cold hearth melting (EBCHM), and the related inclusions formed when using these melting methods. Low-density inclusions are resulted from contamination of air, and high-density inclusions are caused by refractory elements. The formation process of inclusions was analysed. The removal mechanism of different kinds of inclusions was specified. Low-density inclusions are removed mainly by resolving. This is a comprehensive process containing reaction diffusion. The resolving rate of high-density inclusions is so low that these inclusions are mainly removed by sedimentation. The experiments and physical models of inclusions are detailed. In various melting methods, vacuum arc melting is prominent. However, this method cannot remove inclusions effectively, which usually results in repeat melting. Electron beam cold hearth melting has the best ability of removing inclusions. These results can provide instructions to researchers of titanium and titanium alloys. [ABSTRACT FROM AUTHOR]

This paper presents the erosion results of the AISI H13 steel impinged by resin-bonded silica sand, using a testing rig that closely simulates the real blowing conditions during industrial core-making. Steel specimens were heat treated to obtain hardness of 294, 445 and 595 HV200 (29, 45 and 55 HRC). Erosion tests were carried out at impingement angles from 20° to 90° and air drag pressures of 1.38, 2.07 and 2.76 bar (20, 30 and 40 psi). The main results are summarized as follows: (i) The harder material, the lower erosion; (ii) the maximum erosion rate is at 30°; (iii) Little difference in erosion rate at impact angle of 60° and 90° for a constant pressure tested regardless of the hardness level; (iv) As the pressure increases, so does the erosion rate, being more sensitive for low impact angles. Finally, a differential form of the general erosion equation is applied on a practical core-making case to evaluate the erosion rate of the H13 steel at 30° and 90° impingement angles. [ABSTRACT FROM AUTHOR]

During the production of SG iron, the selection of raw materials and control of chemical composition are most important. From the very early days of SG iron production, the effects of trace elements on graphite form and matrix structure have been studied, and the allowable concentration limits for their detrimental influence has been decreased year by year, during the last fifty years. This paper has reviewed some of the suggested SG iron trace elements in the literature and in several Chinese foundries. It was found that for most SG iron castings, rare earth elements are still required to neutralize the harmful effects of trace elements and improve SG iron quality. It also found that the use of high purity and ultra-high purity base iron melts enabled integrated, safety-critical and complicated SG iron castings of varying thickness, and heavy-section, to be produced successfully. These SG iron castings have surprisingly good structures, and their mechanical and dynamic properties are vastly superior to those specified in current international SG iron standards. Further study is required on the effects of using high purity and ultra-high purity base melts on the structure and properties of SG iron. [ABSTRACT FROM AUTHOR]

Since the USA patent of electroslag remelting (ESR) metallurgy was held by P. K. Hopkins in 1940, the ESR technology has now entered a relatively mature stage after a 70-year history of development. At present, the annual capacity of ESR steels around the world is approximately 2 million tonnes. ESR metallurgy emerged in China in 1958. Since then, electroslag furnaces were gradually installed in Chinese special steel plants. At present, there are more than 200 electroslag remelting furnaces in the metallurgical workshops of these steel plants with an annual production capacity of about 500,000 tonnes of ingots and components made of about 200 varieties of steels, including high quality steels and superalloys. This ESR technology is used as a special remelting and refining method for producing high quality steels and superalloys. However, traditional ESR technology has the disadvantages of environmental pollution and extremely high specific power consumption. High power consumption restricts, to a certain degree, the competitiveness of ESR steels in the marketplace. The measures of power saving in ESR have been researched in recent years. In this paper, some factors influencing power consumption, such as filling ratio, slag system, slag amount, melting rate and furnace structure are reviewed, and several new ESR technologies for power saving are proposed. [ABSTRACT FROM AUTHOR]

This paper focuses on the possibility of using the biodegradable materials as binders (or parts of binders' compositions) for foundry moulding and core sands. Results showed that there is a great possibility of using available biodegradable materials as foundry moulding sand binders. Using biodegradable materials as partial content of new binders, or additives to moulding sands may not only decrease the toxicity and increase reclamation ability of tested moulding sands, but also accelerate the biodegradation rate of used binders, and the new biodegradable additive (PCL) did not decrease the strength and thermal properties. In addition, using polycaprolactone (PCL) as a biodegradable material may improve the flexibility of moulding sands with polymeric binder and reduce toxicity. [ABSTRACT FROM AUTHOR]

Seventy percent of new product cost is committed in the design phase. Therefore, the cost needs to be minimized. Incorporating accurate cost estimation capabilities into manufacturing processes can help industries to minimize the cost and optimize the design. The casting process has been employed as a key process to manufacture parts having the advantage of low cost and customized products in foundry industry. This paper presents a cost estimation system for the casting process based on the design features, which incorporates the casting information at the design stage of castings. It aims to deliver the best cost-effective choice for casting design features of a product. Two kinds of knowledge, namely economical knowledge (describing the relation between the casting design considerations and the cost) and technical knowledge (involving the material of the casting features) were structured in this research work. On the basis of the minimum product cost, casting material selection can be carried out in detail. The developed system has been validated through an industrial case study. [ABSTRACT FROM AUTHOR]

Simulation of the microstructure evolution during solidification is greatly beneficial to the control of solidification microstructures. A phase-field method based on the full threaded tree (FTT) for the simulation of casting solidification microstructure was proposed in this paper, and the structure of the full threaded tree and the mesh refinement method was discussed. During dendritic growth in solidification, the mesh for simulation is adaptively refined at the liquid-solid interface, and coarsened in other areas. The numerical results of a three-dimension dendrite growth indicate that the phase-field method based on FTT is suitable for microstructure simulation. Most importantly, the FTT method can increase the spatial and temporal resolutions beyond the limits imposed by the available hardware compared with the conventional uniform mesh. At the simulation time of 0.03 s in this study, the computer memory used for computation is no more than 10 MB with the FTT method, while it is about 50 MB with the uniform mesh method. In addition, the proposed FTT method is more efficient in computation time when compared with the uniform mesh method. It would take about 20 h for the uniform mesh method, while only 2 h for the FTT method for computation when the solidification time is 0.17 s in this study. [ABSTRACT FROM AUTHOR]

This paper reviews the original work of the authors published recently, describing the influence of B on the matrix of the Cuadded spheroidal graphite cast iron. The effect of Cu has been corrected as a ferrite formation promoter in the matrix of the grey cast iron by the usage of high-purity material. Also, this paper focuses on the ferrite formation and the observation of the Cu distribution in the B-added and B-free Cu-containing spheroidal graphite cast iron. The Cu film on the spheroidal graphite can be successfully observed in the B-free sample using a special etching method. However, in the B-added sample, no Cu film could be found, while the secondary graphite was formed on the surface of the spheroidal graphite. The interaction between B and Cu is stressed as a peculiar phenomenon by the employment of a contrast experiment of B and Mn. The heat treatment could make Cu precipitate more significantly in the eutectic cells and in the matrix in the form of large Cu particles because of the limited solubility of Cu. [ABSTRACT FROM AUTHOR]

The article profiles Keung Wing Ching, vice chairman and chief executive officer at Ka Shui International Holdings Ltd. In China. It states that Keung worked for the Hong Kong Productivity Council (HKPC) and for nearly 30 years he has been active in diecasting and foundry industry. It mentions that Keung published various academic papers and academic reports.

The microstructure and mechanical properties of magnesium (Mg) alloys are significantly influenced by the casting process. In this paper, a comparative study on microstructure and mechanical properties at ambient and elevated temperatures of AZ91-2wt.% Ca (AZX912) Mg alloy samples prepared by gravity casting (GC), squeeze casting (SC) and rheo-squeeze casting (RSC), respectively, was carried out. The results show that α-Mg grains in SC and RSC samples are significantly refined compared to the GC sample. The average secondary dendritic arm spacing of AZX912 alloy samples decreases in the order of GC, SC and RSC. As testing temperature increases from 25 °C to 200 °C, strength of AZX912 alloy samples is reduced, while their elongation is increased continuously. Compared to GC and SC processes, RSC process can improve the mechanical properties of AZX912 alloy at both ambient and elevated temperatures. The enhancement of mechanical properties of RSC sample over GC and SC samples mainly results from grain refinement in the as-cast microstructure of AZX912 alloy. [ABSTRACT FROM AUTHOR]

Casting speed, casting temperature and secondary cooling water flow rate are the main process parameters affecting the DC casting process. These parameters significantly influence the flow and temperature fields during casting, which are crucial for the quality of the ingot and can determine the success or failure of the casting operation. Numerical simulation, with the advantages of low cost, rapid execution, and visualized results, is an important method to study and optimize the DC casting process. In the present work, a simulation model of DC casting 2024 aluminum alloy was established, and the reliability of the model was verified. Then, the influence of casting parameters on flow field and temperature field was studied in detail by numerical simulation method. Results show that with the increase of casting speed, the melt flow becomes faster, the depths of slurry zone and mushy zone increase, and the variation of slurry zone depth is greater than that of mushy zone. With an increase in casting temperature, the melt flow rate increases, the depth of the slurry zone becomes shallower, and the depth of the mushy zone experiences only minor changes. The simulation results further indicate that the increase of the flow rate of the secondary cooling water slightly reduces the depths of both slurry and mushy zone. [ABSTRACT FROM AUTHOR]

This study examined the impact of current solution treatment on the microstructure and mechanical properties of the Co-28Cr-6Mo-0.22C alloy investment castings. The findings reveal that the current solution treatment significantly promotes the dissolution of carbides at a lower temperature. The optimal conditions for solution treatment are determined as a solution temperature of 1,125 °C and a holding time of 5.0 min. Under these parameters, the size and volume fraction of precipitated phases in the investment castings are measured as 6.2 µm and 1.1vol.%. The yield strength, ultimate tensile strength, and total elongation of the Co-28Cr-6Mo-0.22C investment castings are 535 MPa, 760 MPa, and 12.6%, respectively. These values exceed those obtained with the conventional solution treatment at 1,200 °C for 4.0 h. The findings suggest a phase transformation of M23C6s+C following the current solution treatment at 1,125 °C for 5.0 min. In comparison, the traditional solution treatment at 1,200 °C for 4.0 h leads to the formation of M23C6 and M6C carbides. It is noteworthy that the non-thermal effect of the current during the solution treatment modifies the free energy of both the matrix and precipitation phase. This modification lowers the phase transition temperature of the M23C6s+C reaction, thereby facilitating the dissolution of carbides. As a result, the current solution treatment approach achieves carbide dissolution at a lower temperature and within a significantly shorter time when compared to the traditional solution treatment methods. [ABSTRACT FROM AUTHOR]

Lattice metamaterials based on three-period minimum surface (TPMS) are an effective means to achieve lightweight and high-strength materials which are widely used in various fields such as aerospace and ships. However, its vibration and noise reduction, and damping properties have not been fully studied. Therefore, in this study, the TPMS structures with parameterization were designed by the method of surface migration, and the TPMS structures with high forming quality was manufactured by laser powder bed fusion (LPBF). The mechanical properties and energy absorption characteristics of the beam and TPMS structures were studied and compared by quasi-static compression. The modal shapes of the beam lattice structures and TPMS structures were obtained by the free modal analysis, and the damping properties of two structures were obtained by modal tests. For the two structures after heat treatment with the same porosity of 70%, the yield strength of the beam lattice structure reaches 40.76 MPa, elastic modulus is 20.38 GPa, the energy absorption value is 32.23 MJ·m-3, the damping ratio is 0.52%. The yield strength, elastic modulus, energy absorption value, and damping ratio of the TPMS structure are 50.74 MPa, 25.37 GPa, 47.34 MJ·m-3, and 0.99%, respectively. The results show that TPMS structures exhibit more excellent mechanical properties and energy absorption, better damping performance, and obvious advantages in structural load and vibration and noise reduction compared with the beam lattice structures under the same porosity. [ABSTRACT FROM AUTHOR]

Cracks have consistently been a significant challenge limiting the development of additive manufactured nickel-based superalloys. It is essential to investigate the location of cracks and their forming mechanism. This study extensively examines the impact of solidification process, microstructural evolution, and stress concentration on crack initiation during direct energy deposition (DED). The results emphasize that the crack formation is significantly related to large-angle grain boundaries, rapid cooling rates. Cracks caused by large-angle grain boundaries and a fast-cooling rate predominantly appear near the edge of the deposited samples. Liquation cracks are more likely to form near the top of the deposited sample, due to the presence of eutectics. The secondary dendritic arm and the carbides in the interdendritic regions can obstruct liquid flow during the final stage of solidification, which results in the formation of solidification cracks and voids. This work paves the way to avoid cracks in nickel-based superalloys fabricated by DED, thereby enhancing the performance of superalloys. [ABSTRACT FROM AUTHOR]

The as-cast amorphous Ti48Zr27Cu6Nb5Be14 composites, comprising in situ formed β-Ti ductile crystalline precipitates, were prepared by water cooled copper mold suction casting. Then, the semi-solid composites were obtained after the as-cast composites were treated by semi-solid isothermal treatment. The microstructure evolution and kinetics of the composites were examined. Results show that the microstructures of both the as-cast and semi-solid composites comprise of β-Ti crystal phases and amorphous matrix phases. Before and after treatment, the crystals evolve from fine granular or fine dendritic crystals to coarse crystals. As the treatment temperature increasing or the time prolonging, the average crystal size gradually increases and the surface morphology of the crystals gradually becomes regular. By studying the microstructural evolution and dynamics during the isothermal treatment process, it is found that the final morphology of β-Ti crystals is influenced by the isothermal treatment temperature and time (t), and the β-Ti evolution rate increases with an increase in treatment temperature. In addition, a linear relationship was observed between the size of cubic β-Ti crystals (D³) and t; the growth kinetics factor K is 3.8 μm³·s-1. As the K value closes to 4 μm³·s-1, it is inferred the morphology evolution of β-Ti crystals is a coarsening behavior controlled by the diffusion of solute elements. [ABSTRACT FROM AUTHOR]

TiZrTaNb-based high-entropy alloys (HEAs) are research frontier of biomedical materials due to their high hardness, good yield strength, excellent wear resistance and corrosion resistance. Sn, as an essential trace element in the human body that plays a significant role in physiological process. It has stable chemical properties and a low elastic modulus. In this study, a new material, TiZrTaNbSn HEAs, was proposed as a potential biomedical alloy. The Ti35Zr25Ta15Nb15Sn10 biomedical high-entropy alloys (BHEAs) were successfully prepared through an arc melting furnace and then remelted using a German high-temperature and high-pressure apparatus under GPa-level (4 GPa and 7 GPa). The precipitation behavior of the needle-like HCP-Zr5Sn3 phase that precipitates discontinuously at the grain boundary was successfully controlled. The phase constitution, microstructure, and corrosion resistance of the alloy were studied. The results show that the needle-like HCP-Zr5Sn3 phase is eliminated and the (Zr, Sn)-rich nanoprecipitated phase is precipitated in the microstructure under high pressure, which leads to the narrowing of grain boundaries and consequently improves the corrosion resistance of the alloy. In addition, the formation mechanisms of (Zr, Sn)-rich nanoprecipitates in BHEAs were discussed. More Zr and Sn dissolve in the matrix due to the effect of high pressure, during the cooling process, they precipitate to form a (Zr, Sn)-rich nano-precipitated phase. [ABSTRACT FROM AUTHOR]

The AA5052 aluminum alloy is widely used in automobile and aerospace manufacturing, and with the development of light-weight alloys, it is required that these materials exhibit better mechanical properties. Previous studies have demonstrated that the addition of Sc to aluminum alloys can improve both the microstructure and properties of the alloys. In this study, the effect of Sc on the Fe-rich phase and properties of the AA5052 aluminum alloy was studied by adding 0%, 0.05%, 0.2%, and 0.3% Sc. The results show that with the increase of Sc, the coarse needle-like Fe-rich phase gradually transforms into Chinese-script and then nearly spherical particles, reduce the size of Fe-rich phase, and refine the grain with increase of high angle grain boundaries (HAGBs). These microstructure changes enhance the strength of the AA5052 alloy through Sc addition. The ductility of the alloy is obviously improved because the addition of a lower amount of Sc changes the morphology of Fe-rich phase from needle-like into a Chinese-script, and it is subsequently reduced as a result of significant increase in HAGBs with increasing Sc content. [ABSTRACT FROM AUTHOR]

Macrosegregation is a critical factor that limits the mechanical properties of materials. The impact of equiaxed crystal sedimentation on macrosegregation has been extensively studied, as it plays a significant role in determining the distribution of alloying elements and impurities within a material. To improve macrosegregation in steel connecting shafts, a multiphase solidification model that couples melt flow, heat transfer, microstructure evolution, and solute transport was established based on the volume-averaged Eulerian-Eulerian approach. In this model, the effects of liquid phase, equiaxed crystals, columnar dendrites, and columnar-to-equiaxed transition (CET) during solidification and evolution of microstructure can be considered simultaneously. The sedimentation of equiaxed crystals contributes to negative macrosegregation, where regions between columnar dendrites and equiaxed crystals undergo significant A-type positive macrosegregation due to the CET. Additionally, noticeable positive macrosegregation occurs in the area of final solidification in the ingot. The improvement in macrosegregation is beneficial for enhancing the mechanical properties of connecting shafts. To mitigate the thermal convection of molten steel resulting from excessive superheating, reducing the superheating during casting without employing external fields or altering the design of the ingot mold is indeed an effective approach to control macrosegregation. [ABSTRACT FROM AUTHOR]

Stainless steels are used in a wide range of complex environments due to their excellent corrosion resistance. Multiphase stainless steels can offer an excellent combination of strength, toughness and corrosion resistance due to the coexistence of different microstructures. The microstructure and mechanical properties of a novel cast multiphase stainless steel, composed of martensite, ferrite, and austenite, were investigated following appropriate heat treatment processes: solution treatment at 1,050 °C for 0.5 h followed by water quenching to room temperature, and aging treatment at 500 °C for 4 h followed by water quenching to room temperature. Results show reversed austenite is formed by diffusion of Ni element during aging process, and the enrichment of Ni atoms directly determines the mechanical stability of austenite. The austenite with a lower Ni content undergoes a martensitic transformation during plastic deformation. The tensile strength of the specimen exceeds 1,100 MPa and the elongation exceeds 24% after solid solution, and further increases to 1,247 MPa and 25% after aging treatment. This enhancement is due to the TRIP effect of austenite and the precipitation of the nanoscale G-phase pinning dislocations in ferrite and martensite. [ABSTRACT FROM AUTHOR]

This paper presents a technique for controlling the pressure of a molten metal when using a new type of iron casting method called sand mold press casting to realize high productivity and obtain high-quality products. The past test results using this method showed a casting yield of 90% to 95%, while conventional methods only show a casting yield of 60% to 70%. Although the press casting method does not require a sprue cup or runner channel casting defects such as metal penetration are often caused by the high pressure in the high-velocity pressing part of this casting process. Therefore, we proposed a pressure control method with a mathematical model of molten metal pressure, and with it we achieved experimental confirmation of the successful production of brake drums at different pressing temperatures. Results show that the proposed pressing control method can realize sound, penetration-free casting production. However, the theoretical analysis and design of this pressing process had not previously been studied sufficiently, and therefore this paper presents the theoretical design algorithm for the process as well as its experimental confirmation. [ABSTRACT FROM AUTHOR]

3D printing is such a magical technology that it extends into almost every sector relating to manufacturing, not to mention casting production. In this paper, the past, present and future of 3D printing in the foundry sector are profoundly reviewed. 3D printing has the potential to supplement or partially replace the casting method. Today, some castings can be directly printed by metal powders, for example, titanium alloys, nickel alloys and steel parts. Meanwhile, 3D printing has found an unique position in other casting aspects as well, such as printing the wax pattern, ceramic shell, sand core, sand mould, etc. Most importantly, 3D printing is not just a manufacturing method, it will also revolutionize the design of products, assemblies and parts, such as castings, patterns, cores, moulds and shells in casting production. The solid structure of castings and moulds will be redesigned in future into truss or spatially open and skeleton structures. This kind of revolution is just sprouting, but it will bring unimaginable impact on manufacturing including casting production. Nobody doubts the potential of 3D printing technologies in manufacturing, but they do have limitations and drawbacks. [ABSTRACT FROM AUTHOR]

This paper includes studies on the influence of grain refinement treatment with respect to the composition and structure of high zinc aluminium casting alloys on the changes of their tensile properties. The Al- 20wt.%Zn alloy was inoculated with master alloys AlTi5B1 and AlTi3C0.15 to determine the impact of a variable titanium addition on the tensile properties of AlZn20 alloy, and determine on this basis an optimal addition of Ti that would ensure the improvement of elongation of alloys cast in the sand mould, at the same time maintaining high tensile strength. Within the studies, light microscopy (LM) and strength tests were applied. Experimental results showed that the inoculation of high zinc aluminium alloy AlZn20 with the master alloys AlTi5B1 and AlTi3C0.15 causes intensive structure refinement, while the intensity of reaction of both master alloys is comparable. The AlTi3C0.15 master alloy addition, selected for further studies, introducing about 100 ppm Ti, enhances the tensile properties of the alloy; the elongation increases about 20% and tensile strength increases about 10% against the initial values (uninoculated alloy). Further increase of the Ti addition up to 500-600 ppm leads to the "overinoculation" effect that is accompanied by the decrease of elongation. Therefore,the Ti addition should be reduced to the level of about 100 ppm which ensures obtaining a set of optimal properties. [ABSTRACT FROM AUTHOR]

Shrinkage porosity is a type of random distribution defects and exists in most large castings. Different from the periodic symmetry defects or certain distribution defects, shrinkage porosity presents a random "cloud-like" configuration, which brings difficulties in quantifying the effective performance of defected casting. In this paper, the influences of random shrinkage porosity on the equivalent elastic modulus of QT400-18 casting were studied by a numerical statistics approach. An improved random algorithm was applied into the lattice model to simulate the "cloud-like" morphology of shrinkage porosity. Then, a large number of numerical samples containing random levels of shrinkage were generated by the proposed algorithm. The stress concentration factor and equivalent elastic modulus of these numerical samples were calculated. Based on a statistical approach, the effects of shrinkage porosity's distribution characteristics, such as area fraction, shape, and relative location on the casting's equivalent mechanical properties were discussed respectively. It is shown that the approach with randomly distributed defects has better predictive capabilities than traditional methods. The following conclusions can be drawn from the statistical simulations: (1) the effective modulus decreases remarkably if the shrinkage porosity percent is greater than 1.5%; (2) the average Stress Concentration Factor (SCF) produced by shrinkage porosity is about 2.0; (3) the defect's length across the loading direction plays a more important role in the effective modulus than the length along the loading direction; (4) the surface defect perpendicular to loading direction reduces the mean modulus about 1.5% more than a defect of other position. [ABSTRACT FROM AUTHOR]

Deformation of casting during the solidification process has puzzled many engineers and scientists for years. In order to attain the goal of near-net forming by casting, numerical simulation is a powerful tool. Traditional methods compute the thermal stress of both the casting and the mold. This method suffers the problem of massive calculation and failure of convergence. This paper proposes an improved Mold Surface Element Method, the main idea of which is to use the surface elements instead of body elements to express the interactions between the casting and the mold. The proposed method shows a high computation efficiency and provides satisfactory precision for engineering. Two practical casting products were used to verify the proposed method. The simulated results agree well with those observed in practical products. The proposed method is believed to benefit production practice and to provide theoretical guidance. [ABSTRACT FROM AUTHOR]

It is known that phosphorus can refine the primary silicon and heat treatment can spheroidize the eutectic silicon. This paper presents an optimal combination of heat treatment processes and P refinement on hypereutectic Al-Si alloy. The optimal P addition amount, and the solution and aging temperatures for Al-25%Si alloy were obtained through the orthogonal experiment, and their modification effects were discussed. The results show that P addition has the greatest modification effect, followed by aging temperature, and the modification effect of solution temperature is the least. The optimized modification parameters are: addition of 0.6% P, solution at 540 ºC and aging at 160 ºC . In addition, the cooling curve, superheating and hardness of the alloy were also analyzed. [ABSTRACT FROM AUTHOR]

The paper describes the investigation of mechanisms of cast structure formation in Hadfield steel depending on the changes in the cooling rate of a casting in the following two temperature ranges: crystallization temperature (1,200-1,390 °C) and the temperature of excessive phase separation (560-790 °C). Changes in the cooling rate of the crystallization temperature range from 1.1 to 25.0 °C·s-1 result in the reduction of the average size of austenite grains from 266 to 131 μm. At the same time, the magnitude of developing shrinkage stresses changes from +195 to 0 MPa. When the cooling rate is higher than 16 °C·s-1, no shrinkage stresses are formed in the casting. Changes in the cooling rate of the casting in the temperature range of the excessive phase separation influence the number of phases, their morphology and chemical composition, the values of phase stresses, and the possibility of martensitic transformation. Changing in the cooling rate from 0.24 to 5.46 °C·s-1 results in the decrease of the amount of the excessive phase from 14.8% to 2.1%, which is composed of eutectic and carbides depending on the cooling rate, their quantitative ratio and morphology change. Such changes in the microstructure are reflected on the changes of value of developing phase stresses. When the cooling rate is 0.24 °C·s-1, it is +100 MPa, while the increase of the cooling rate to 1.4 °C·s-1 results in the decrease of tensile stresses to 0 MPa and their qualitative stresses change to compressive ones. Further increase of the cooling rate results in the increase of the value of compressive stresses. When the cooling rate is 5.5 °C·s-1, their value reaches -92 MPa. Martensite forming in the structure of Hadfield steel is possible if the cooling rate of the casting in the range of excessive phase separation is less than 0.25 °C·s-1. [ABSTRACT FROM AUTHOR]

The paper presents the research results of using an innovative method to reclaim the waste moulding sands containing water glass. Two of the examined processes are connected with "dry" or "wet" activation of inorganic binder in waste moulding sand mixtures physically hardened by microwave radiation. The sand mixtures consisting of high-silica sand and water-glass with average molar module 2.5, were subjected to the following cyclical process: mixing the components, compacting, microwave heating, cooling-down, thermally loading the mould to 800 °C, cooling-down to ambient temperature, and knocking-out. After being knocked-out, the waste moulding sands were subjected to either dry or wet activation of the binder. To activate thermally treated inorganic binder, each of the examined processes employed the surface phenomenon usually associated to mechanical reclamation. The study also covered possible use of some elements of wet reclamation to rehydrate waste binder. To evaluate the effectiveness of the two proposed methods of waste binder activation, selected strength and technological parameters were measured. After each subsequent processing cycle, the permeability, tensile strength and bending strength were determined. In addition, the surface of activated sand grains was examined with a scanning electron microscope. Analysis of the results indicates that it is possible to re-activate the used binder such as sodium silicate, and to stabilize the strength parameters in both activation processes. Permeability of the refreshed moulding sands strongly depends on the surface condition of high-silica grains. The wet activation process by wetting and buffering knocked-out moulding sands in closed humid environment makes it possible to reduce the content of refreshing additive in water-glass. The moulding sands cyclically prepared in both processes do not require the addition of fresh high-silica sand. The relatively high quality achieved in the refreshed moulding sands allows them to be reused for manufacture of next moulds. Thus, the two proposed methods for cyclically processing used moulding sands containing sodium silicate, subject to microwave hardening, are suitable for economic and ecological circulation moulding mixtures. [ABSTRACT FROM AUTHOR]

The corundum (α-alumina) core has been considered as a suitable candidate for investment casting of hollow, high pressure turbine engine airfoils due to its excellent properties. However, the efficiency of removing alumina cores in concentrated caustic solution cannot meet the needs of industrial production. In this paper, the effects of temperature and initial solution concentration on dissolution of α-alumina were studied by the classical weight-loss method. The fractal kinetic model was developed in order to describe α-alumina dissolution, assuming that the nonporous particles shrank during reaction process. The results show that the dissolution rate increases with increasing reaction temperature and initial solution concentration. Especially, the initial solution concentration has a significant influence on α-alumina dissolution rate at a higher reaction temperature. The activation energies decrease with increasing initial solution concentration, and the chemical reaction is the rate-controlling step. [ABSTRACT FROM AUTHOR]

Titanium matrix composites reinforced with ceramic particles are considered a promising engineering material due to their combination of high specific strength, low density, and high modulus. In this study, the TA15-based composites reinforced with a volume fraction of 10% to 25% (TiB+TiC) were prepared using powder metallurgy and casting technique. Microstructural characterization and phase constitution were examined using optical microscopy (OM), scanning electron microscopy (SEM), and X-ray diffraction (XRD). In addition, the microhardness, room temperature (RT) and high temperature (HT) tensile properties of the composites were evaluated. Results revealed that the reinforcements are distributed uniformly even in the composites with a high volume of TiB and TiC. However, as the volume fraction exceeds 15%, TiB and TiC particles become coarsening and exhibit rod-like and dendritic-like morphology. Microhardness increases gradually from 321.2 HV for the base alloy to a maximum of 473.3 HV as the reinforcement increases to 25vol.%. Tensile test results indicate that a reinforcement volume fraction above 20% is beneficial for enhancing tensile strength and yield strength at high temperatures, but it has an adverse effect on room temperature elongation. Conversely, if the reinforcement volume fraction is below 20%, it can improve high-temperature elongation when the temperature exceeds 600 °C. [ABSTRACT FROM AUTHOR]

It is important to improve the comprehensive performance of the ductile iron bars (DIBs) for the cylinder block of the extra high pressure hydraulic plunger pump and accelerate the industrial application. In this work, the LZQT600-3 DIBs with the diameter of 145 mm were prepared by the horizontal continuous casting (HCC) process, that is, LZQT600-3 HCCDIBs. The microstructure and room temperature tensile properties of different sections [left-edge (surface layer), left-1/2R (left half of the radius), and the center of the HCCDIBs] were studied. The results show that the spheroidization of LZQT600-3 HCCDIBs matrix from the left-edge, left1/2R to the center is at nodulizing grade II and above. As the cooling rate gradually decreases from surface to the center of the HCCIBs, the number of spheroidized graphite is gradually reduced, the size is gradually increased, the shape factor is decreased, and the pearlite content and lamellate spacing are increased. Along the horizontal direction of the section, the hardness of the material is distributed symmetrically around the center of the HCCDIBs. In the vertical direction, the hardness distribution in the center of the HCCDIBs is asymmetrical due to the gravity during the solidification process. Therefore, the microstructure in the lower part of the section solidifies relatively quickly. The left-edge has the best tensile mechanical properties, and the ultimate tensile strength, yield tensile strength and elongation are 597.3 MPa, 418.5 MPa and 9.6%, respectively. The tensile fracture belongs to the ductile-brittle hybrid fracture. The comprehensive performances of LZQT600-3 HCCDIBs meet the actual application requirements of ultra-high pressure hydraulic plunger pump cylinder. [ABSTRACT FROM AUTHOR]