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Forming complex geometries using the casting process is a big challenge for bulk metallic glasses (BMGs), because of a lack of time of the window for shaping under the required high cooling rate. In this work, we open an approach named the “entire process vacuum high pressure die casting” (EPV-HPDC), which delivers the ability to fill die with molten metal in milliseconds, and create solidification under high pressure. Based on this process, various Zr-based BMGs were prepared by using industrial grade raw material. The results indicate that the EPV-HPDC process is feasible to produce a glassy structure for most Zr-based BMGs, with a size of 3 mm × 10 mm and with a high strength. In addition, it has been found that EPV-HPDC process allows complex industrial BMG parts, some of which are hard to be formed by any other metal processes, to be net shaped precisely. The BMG components prepared by the EVP-HPDC process possess the advantages of dimensional accuracy, efficiency, and cost compared with the ones formed by other methods. The EVP-HPDC process paves the way for the large-scale application of BMGs.

The paper reports an experimental study of die-casting dies with conformal cooling fabricated by direct-metal additive techniques. The main objective is to compare the benefits and limitations of the application to what has been widely discussed in literature in the context of plastics injection molding. Selective laser melting was used to fabricate an impression block with conformal cooling channels designed according to part geometry with the aid of process simulation. The tool was used in the manufacture of sample batches of zinc alloy castings after being fitted on an existing die in place of a machined impression block with conventional straight-line cooling channels. Different combinations of process parameters were tested to exploit the improved performance of the cooling system. Test results show that conformal cooling improves the surface finish of castings due to a reduced need of spray cooling, which is allowed by a higher and more uniform cooling rate. Secondary benefits include reduction of cycle time and shrinkage porosity.

Large functionally integrated casting and electrification are rapidly changing the high-pressure die-casting industry. The requirements for these new castings differ from those of the previous ones. Load-bearing capability, fatigue, ductility, and crashworthiness all increase, and the foundry’s readiness for this varies and is challenging. At the same time, the carbon footprint needs to be reduced, meaning that recycled, secondary aluminium usage is required, making the challenge of attaining the required component performance significantly more difficult. The current paper examined the conditions and requirements to manage and reach the required targets, both from a material standpoint as well as from a climate impact and resource-efficiency perspective.

This paper presents the effect of hot-chamber HPDC (high-pressure die casting) process parameters on the porosity, mechanical properties, and microstructure of AM60 magnesium alloy. To reduce costs, a Taguchi design of the experimental method was used to optimise the HPDC process. Six parameters set at two levels were selected for optimisation, i.e., piston speed in the first phase, piston speed in the second phase, molten metal temperature, piston travel, mould temperature, and die-casting pressure (the pressure under the piston). Signal-to-noise (S/N) ratios were used to quantify the present variations. The significance of the influence of the HPDC parameters was assessed using statistical analysis of variance (ANOVA). The results showed that the die-casting pressure had the most significant influence on the porosity of the AM60 alloy. Moreover, piston speed in the first phase, second phase, and die-casting pressure had the most important effects on tensile strength. It is well known that porosity determines the mechanical properties of die castings; however, in AM60 alloy, changes in the HPDC parameters also contribute to microstructural changes, mainly through the formation of Externally Solidified Crystals.

The selection of manufacturing processes for a given application is a complex problem of multicriteria decision-making although there have been several different approaches that can be utilized to select a suitable alternative. However, identifying appropriate multicriteria decision-making approach from the list of available methods for a given application is a difficult task. This work suggests a methodology to assess different selection approaches, which are the technique for order of preference by similarity to ideal solution (TOPSIS), analytic hierarchy process (AHP), and VIKOR: stepwise procedure. This valuation was done depending on the following factors: number of alternative processes and criteria, agility through the process of decision-making, computational complexity, adequacy in supporting a group decision, and addition or removal of a criterion. A case study in this study was presented to analyse the evaluation methodology. The criteria used to evaluate and identify the best manufacturing process were categorized into productivity, accuracy, complexity, flexibility, material utilization, quality, and operation cost. Five manufacturing processes were considered, including gravity die casting, investment casting, pressure die casting, sand casting, and additive manufacturing. The results showed that each approach was suitable for the problems of manufacturing process selection, in particular toward the support of group decision-making and uncertainty modelling. Manufacturing processes were ranked based on their respective weights for AHP, TOPSIS, and VIKOR, and sand casting is the best. In terms of computational complexity, the VIKOR method performed better than TOPSIS and AHP. Moreover, the VIKOR and TOPSIS methods were better convenient to the selection of manufacturing processes for agility during the process of decision-making, the number of alternative processes and criteria, adequacy in supporting a group decision, and addition or removal of a criterion.

The paper deals with the FEM (Finite Element Method) simulation of rotary swaging of Dievar alloy produced by additive manufacturing technology Selective Laser Melting and conventional process. Swaging was performed at a temperature of 900°C. True flow stress-strain curves were determined for 600°C–900°C and used to construct a Hensel-Spittel model for FEM simulation. The process parameters, i.e., stress, temperature, imposed strain, and force, were investigation during the rotary swaging process. Firstly, the stresses induced during rotary swaging and the resistance of the material to deformation were investigated. The amount and distribution of imposed strain in the cross-section can serve as a valuable indicator of the reduction in porosity and the texture evolution of the material. The simulation revealed the force required to swag the Dievar alloy. It also showed the evolution of temperature, which is important for phase transformation during solidification. Furthermore, microstructure evolution was observed before and then after rotary swaging. Dievar alloy is a critical material in the manufacture of dies for high-pressure die casting, forging tools, and other equipment subjected to high temperatures and mechanical loads. Understanding its viscoelastoplastic behavior under rotary swaging conditions is essential to optimize its performance in these demanding industrial applications.

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

This article presents studies on the effect of Sr and TiB on the crystallization process, mechanical properties, hardness, and density index of the Al-Si alloy from the EN AC-46000 group, with a narrowed chemical composition, produced by die-casting and HPDC (high-pressure die casting) technology. The research used the Box–Wilson method to design the experiment and stepwise multiple regression. To identify the optimal amount of Sr and Ti in the analyzed alloy that would simultaneously guarantee the maximization of UTS, YS, Agt, and HBW and the minimization of the DI (density index), multi-criteria optimization was performed. The modifiers were added to the liquid alloy as AlSr10 and AlTi5B1 master alloys. It was found that for 0.02–0.04 wt.% Sr and 0.05–0.08 wt.% Ti in the die castings, the highest mechanical properties, such as UTS, YS, Agt, and HBW (treated as stimulants in the experiment), can be obtained simultaneously with the lowest alloy gasification identified by DI (treated as a destimulant in the experiment). It was also confirmed that the same amount of the above-mentioned elements in HPDC castings caused an increase in UTS by approx. 14%, YS by approx. 6%, A by approx. 47%, and HBW by approx. 13%, with a relatively small increase in DI by approx. 5% compared to the unmodified alloy.

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

Die-casting die steel is widely used in the manufacturing of automobile parts and 5G communication equipment. However, it requires high thermal strength and stability during usage. This study investigated the thermal stability and the thermal fatigue resistance as well as the microstructure and composition of the self-developed new Cr3 die-casting die steel 4Cr3Mo2V by using an optical microscope (OM), scanning electron microscope (SEM), energy dispersion spectrum (EDS), and transmission electron microscope (TEM). The experimental results demonstrate that the M 23 C 6 in the testing steel visibly grows and aggregates as the holding time increases. And the M 23 C 6 -type carbides in the 4Cr3Mo2V and 4Cr5Mo2V steels account for 46 and 52% of the total carbides, respectively, especially when the temperature is maintained at 600 °C for 64 h. The lower percentage M 23 C 6 carbides in 4Cr3Mo2V steel have improved the thermal stability and thermal fatigue resistance of the steel.