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Light metals such as aluminum alloys which are being broadly used in automobile sideways, aerospace production as well as segments in military. A light-weight metals prominent for energy consume reduction, efficiency of gasoline and oil increment and superior security to environment. The main utilization of aluminum matrix alloy components have been manufactured by the appropriate behaviors of high tensile strength, hardness, decent machinability, great cast-ability and excessive resistance of corrosion. In the present investigation dealing with casting and heat treatment processes of aluminum alloys 6063 by two different methods such as Sand casting and Die casting. The characterization of AA6063 are analyzed with help of destructive and non-destructive techniques. Finally the results indicates that die casted material gives better results when it is heat treated than the sand casted material.

The lightest structural metal present on Earth’s surface is Magnesium (Mg). Mg is very useful for many applications like automobile, aeronautical etc. Mg has many limitations and because of which it cannot be used directly as a replacement of steel and aluminum. Different alloys of magnesium have been developed to partially or completely overcome the limitations of magnesium without sacrificing other properties. The most commonly used commercial alloys are in almost all the fields is magnesium alloy AZ91, which gives better properties than magnesium. This paper mainly aims at study the mechanical properties of magnesium based AZ91 alloy. The results were compared with the as-cast condition. Present investigated material has been obtained by using die casting technique. Mg material is subjected to T6 heat treatment which has two stage process involving combination of solution annealing at 413 °C for 13 h and subsequent aging at 200 °C for 10 h. Micro structural and mechanical properties like hardness of the specimen were studied. Useful survey shows that hot working of AZ91 alloy provides high mechanical properties unattainable by cast material subjected to heat treatment. The microstructure is observed under the optical microscope.

Aluminum alloys are widely used in the production of aerospace, aircraft, and automotive components. The die casting components are subjected to post-processing operations, such as milling and turning operations to get final shape, surface finish, and dimensional tolerances. During machining operations large quantities of material are removed from the cast components in the form of chips to achieve final shape and size. The chips that are produced during machining operations are mixed with oils, lubricants. This article discusses how effectively the aluminum can be recovered from the chips with maximum metal recovery and minimum melting loss without compromising quality and chemical composition. The different types of techniques are employed, and their results are discussed in this paper. Al-Si8Cu3Fe (LM24) alloy is selected for investigation purposes. The recovery techniques, such as with flux, without flux, with different melting furnaces, with different melting temperatures, with or without compacting, are studied.

In this study, in order to clarify the unknown physical properties of the Mg-Al-Th-RE alloy, the relationship between the injection conditions and the internal porosities and the mechanical properties exerted by the solidification microstructure were investigated. The obtained cast samples were investigated using X-ray CT internal measurements, tensile tests, Vickers hardness tests and solidification microstructure observations. The flow simulation and the X-ray CT analysis results showed that the porosity volume increased as the injection speed increases. The higher injection speed also affected the metal microstructure to become denser, which leads to a higher material strength and hardness. The eutectic phases quickly formed because of the shorter filled and cooled time. Therefore, the growth of the primary phase α-Mg was suppressed. On the other hand, it was considered that the material strength and hardness were greatly reduced by the coarse primary phase.

Currently there is greater interest and an industrial need to create a bond between cast steel and aluminum alloys. The bond quality between these two metals must be considered, since it is affected by several casting techniques and parameters. This research aims to find the right combination of techniques and parameters to make a good bond between cast steel and aluminum alloys. This research systematically used the response surface methodology (RSM). Three important casting techniques and parameters are selected as independent variables, which are preheating temperature of cast steel, pouring temperature of aluminum alloy molten, and surface cleaning of cast steel. The gap between cast steel and aluminum alloy is used as dependent variable, which is defined as the quality measurement of the bond between two metals. The experiments were conducted on 48 samples, in which destructive test was performed in order to measure the gap. From the methodology, it is found that the recommended preheating temperature of cast steel is 491 °C, the recommended pouring temperature of aluminum alloy is 696 °C, and the recommended technique is cleaning the cast steel insert using degreasing. For practical purpose, the preheating temperature of cast steel can be set at 490 ± 10 °C and the pouring temperature of aluminum alloy can be set at 695 ± 10°C. This research limits on bimetal casting between cast steel and aluminum alloys, and the casting process is gravity die casting process. This paper is able to find the best casting techniques and parameters for cast steel and aluminum alloy bond using RSM. This paper also proposes gap bond between two metals as bond quality measurement.

The melting and pouring of liquid molten metal into the mould is part of the casting process. So, care should be taken while selecting the mould material and method of moulding. Due to the better frugality of sand moulds, it is mostly used for ferrous and nonferrous metals production, because metallic moulds wear out too quickly. Sand castings are preferably used for low and medium-size production because die casting and permanent moulds have higher tooling costs. The type of molten metal, the casting method, the ease of access to moulding material, the core and mould manufacturing equipment, and quality criteria all influence the bonding mechanism and mould material chosen. In the optimization of the moulding system, detailed understandings all of these elements are required. This article discusses the processing of moulding sand reclamation systems and environmental issues with different resin binder systems.

This paper presents a re-evaluation of the room temperature mechanical properties and high temperature creep resistance of magnesium die-casting alloy AE44 (Mg-4Al-4RE) in light of the influence of minor Mn addition. It is shown that the Mn-containing AE44 exhibits distinct age hardening response upon direct ageing (T5) due to the precipitation of nanoscale Al-Mn particles, as reported previously in a similar alloy. The T5 ageing leads to a significant improvement in strength with similar ductility. Consequently, the T5-aged AE44 has a remarkably better strength-ductility combination than most Mg die-casting alloys and even the Al die-casting alloy A380. Minor Mn addition is also shown to be critical for the creep resistance of AE44 whereas the influence of the RE constituent is not as significant as previously thought, which reaffirms that precipitation hardening of the α-Mg matrix is more important than grain boundary reinforcement by intermetallic phases for the creep resistance of die-cast Mg alloys. The findings in this work could provide new application perspectives for AE44, particularly in the automotive industry.

The article considers the requirements for protective coatings operating in the conditions of injection molding of non-ferrous metal alloys, among which the most important are the provision of crack resistance and wear resistance of the forming surface. It is revealed that single-layer coatings applied by the physical vapour deposition method, regardless of its composition, are not able to fully meet the formulated requirements. It is established that multilayer coatings provide increased performance of structural elements of molds in comparison with single-layer ones.

There are several constituents which causes die fractures in die casting process. Several features can be managed to a certain level by the help of specialists like geometry experts, production spe...

Die cast alloys have to be poured at temperatures much higher than their liquidus in order to make the alloys castable. Pouring at a high temperature reduces the formation of dendrites in the shot sleeve which tend to choke the flow at the in-gate but causes increased damage to the shot tooling and dies. Forming globular grains in the shot sleeve is an effective way of breaking the limit of fluidity on reducing the pouring temperature in order to increase die life and to improve the integrity of die casting products. This study investigated the feasibility of producing globular grains in a shot sleeve using a water-cooled ultrasound trough for feeding molten metal into the shot sleeve. Globular grains were obtained using this unique trough. The temperature window within which globular grains can be produced for E380 alloy was determined. Without using the WCUST, the grains in the shot sleeve were fully dendritic and the grain size was about 300 µm. When the molten metal was poured over the WCUST, small globular grains were obtained for the entire pouring temperature window, from 610 °C (1130 °F) to 700 °C (1292 °F), tested in this study. Analysis was made on the conditions for obtaining globular grains. The analysis seems in agreement with experimental results. In addition to producing globular grains for die casting applications, the water-cooled ultrasound trough may be suitable for grain refinement of other gravity casting processes.

Pada industri otomotif komponen suku cadang maupun elemen-elemen mesin banyak menggunakan paduan aluminium dengan proses pengecoran, penggunaan paduan aluminium pada pengecoran salah satunya aluminium dengan tembaga (Al-Cu). Pengecoran logam metode die casting merupakan bagian dari pengecoran bertekanan, dimana logam ditekan kedalam cetakan. Banyak industri pengecoran aluminium terutama industri kecil menengah dalam pembuatan produk atau komponen menggunakan material daur ulang dengan metode pengecoran tuang, sehingga akan berpengaruh terhadap penurunan sifat materialnya. Dengan metode die casting diharapkan mampu meningkatkan sifat fisis dan mekanisnya. Proses pengecoran dengan metode die casting dilakukan pada temperatur tuang (650⁰C, 670⁰C, dan 690⁰C) dengan variasi tekanan 0 (tanpa tekanan), 2,5 MPa, 5 MPa, dan 7,5 MPa. Hasil dari pengujian kekerasan menunjukkan pada temperatur tuang 650⁰C dan tekanan 7,5 MPa merupakan kekerasan paling tinggi dengan nilai 72 HB dan nilai kekerasan terendah terdapat pada temperatur 690⁰C tanpa tekanan dengan nilai kekerasan 58 HB. Dari penelitian ini dapat diambil kesimpulan bahwa temperatur tuang dan tekanan sangat berpengaruh terhadap nilai kekerasan pada proses pengecoran dengan metode die casting.

Aluminum alloys are becoming widely preferred in the automotive industry due to their high specific strength-to-weight ratios. Among these aluminum cast alloys, those with high-silicon content can offer a unique combination of mechanical and better wear properties. In this study, EN AC 46000 (AlSi9Cu3(Fe)), 48000 (AlSi12CuNiMg), and 48100 (AlSi17Cu4Mg) aluminum alloys are produced using high-pressure die casting and gas-induced semi-solid (GISS)-adapted technologies. The effects of GISS adaption on the microstructure and tribological behavior are investigated. The lower casting temperatures and formation of solid particles in the melt by GISS adaption were found to improve the die filling and reduced porosity. This leads to higher hardness and improved wear resistance. Among the six casts investigated, the one with GISS-adapted 48100 (AlSi17Cu4Mg) alloy showed the highest hardness and highest abrasion of the cast iron pin during tribological tests. The enhanced properties are assumed to be the result of its unique microstructure formed due to its high-silicon and copper contents, as well as the decreased microporosity due to the GISS (gas-induced semi-solid) adaption approach.

In this study, the characteristic acoustoelastic behaviors of SKD61 hot die steel were revealed, which is useful for nondestructive evaluation technique of die casting mold in view of the Internet of Things (IoT). The measurement principle was investigated from the acoustoelastic effect of diffracted shear horizontal (SH) waves caused by slight increase in elastic modulus and rapid relaxation of residual stress, which accompany the bct-to-bcc phase transformation.

This study investigated a method for accurately predicting the residual stress in die castings manufactured using aluminum alloy. To account for the mechanical properties caused by the material composition differences that occur in the thickness direction of the die castings, a model split in the thickness direction was used in the simulation model. Norton’s law was applied to the constitutive equation of the material, and the stress relaxation phenomenon was examined. The composition of Al-Si-Cu alloy (JIS-ADC12) die castings in the thickness direction were analyzed using scanning electron microscopy and energy dispersive X-ray spectroscopy (SEM-EDS), and differences in composition were confirmed. As a result of calculating the residual stress using the simulation, it was possible to calculate the residual stress that could not be reproduced by the simulation model of uniform composition. This suggested that the difference in mechanical properties of die castings in the micro-region influences the residual stress.

In industry, thermally shocked components lead to early failures and unexpected breakdowns during production resulting in huge losses in profit. Thus, the present study investigates the as-received, hardened and hardened and nitrogen treated H13 tool steels subjected to a thermal shock gradient similar to the actual industrial applications. The thermal shock gradients were created by using an in-house-built thermal shock fatigue cyclic treatment machine. The effect of thermal shock fatigue cyclic treatments at 1000 and 2000 thermal shock cycles in hot and molten metal chambers was noticed. All the thermal shock fatigue cyclic-treated samples were analysed by hardness, X-ray diffraction, microscopy and magnetic tests. The interesting changes in hardness, distorted crystal structure and crack initiation were found to be different for differently treated H13 tool steel specimens. The molten aluminium was more prone to stick to the surface of as-received as well as hardened and nitrogen treated steel compared to the hardened H13 steel specimens, which would delay the crack initiation. The wear resistance properties of the hardened H13 steel specimens were found to be higher than as-received and hardened and nitrogen treated H13 steel specimens after thermal shock fatigue cyclic treatment. The loss in magnetic properties was significant for the hardened and hardened and nitrogen treated samples compared to as-received H13 tool steel specimens. Therefore, the present 1000 and 2000 thermal fatigue cycles for 30 s at 670 °C would be worthy to predict the proper heat treatment method to design the parameters as well as the life of die-casting components and to help in the economical production of casting.

The influence of aluminum on copper (aluminum bronze) produced by die-casting process is reported in this work. Pure copper and aluminum bronze for 5 and 10 wt.% Al are produced by die casting process. Optical micrographs of pure copper, aluminum bronze with 5 and 10 wt.% Al revealed equiaxed grains, dendritic structure and martensite structure, respectively. The density of the copper, 5 and 10 wt.% aluminum bronze are reported as 8484 ± 84, 7991 ± 94 and 7518 ± 40 kg/m3, respectively. The Micro Vickers hardness of the copper, Cu-5 wt.% Al and Cu-10 wt.% Al, respectively, found to be observed as 96.833 ± 4.88, 139.01 ± 4.96 and 257.22 ± 5.85 HV1. The compression strength, wear behavior of pure copper, aluminum bronze of 5 and 10 wt.% Al were investigated by conducting the compression test and wear behavior using pin-on-disk wear test for different speeds and different loads.

In this study, four different Mg-Zn-Ca-Mn alloys were produced using gravity die casting method. Mn content was kept constant in all alloys, while Zn and Ca were added in two different ratios. Homogenization heat treatment was applied to all cast alloys and a specimen from each homogenized alloy was hot rolled. Microstructure, mechanical properties, and corrosion behavior of the homogenized and hot rolled alloys were investigated as comparatively. Following results were obtained; grain size decreased significantly with increasing Zn content, Zn promoted Ca2Mg6Zn3 phase formation, corrosion resistance increased with increasing Zn/Ca atomic ratio, hot rolling resulted in much higher tensile strength but much lower ductility and toughness. Among the homogenized and hot rolled alloys, ZXM300-h alloy (hot rolled ZXM300 alloy) with its 146 ± 2.5 MPa yield strength, 229 ± 3.7 MPa tensile strength,% 1.6 ± 0.1 elongation and 0.029 mm/yr. immersion corrosion rate exhibited the best mechanical properties and corrosion resistance to be used as a biodegradable alloy such as fracture bone plate material.

The injection of light alloys is an activity that requires a high effort on the part of Engineering to maintain its competitiveness. Due to the temperatures used, the wear of the components connected to this manufacturing process is quite intense, requiring a constant updating effort. This work was developed with a view to solving problems related to the excessive wear of injection nozzles used in the die casting process, and corresponding electrical resistances, with a view to increase its lifetime and improve the competitiveness of the process in the injection of low-cost parts in zamak for the automotive industry. To study and solve the problems of premature wear of the injection nozzles, the action-research method was used, which, through several iterations, allowed to arrive at an improved design of the nozzle, as well as the corresponding electrical resistance, thus increasing the life span of these components, also improving safety around the process and generating knowledge that can be transferable to other similar situations., The authors would like to thank Mr. Mário Cardoso from FicoCables, Lda. for his continuous support, proving interesting challenges for applied research. Authors would like to thank Ing. Fátima Andrade due to her help in preparing the samples and collecting images in the optical microscope. Authors would also thank INEGI - Instituto de Ciência e Inovação em Engenharia Mecânica e Engenharia Industrial, Porto, Portugal, due to its continuous support.

In the present study, the effect of an La alloying element with different quantities (1, 3 and 5 wt.-%) on the microstructure, mechanical and dry sliding wear properties of Mg- 3Al-3Sn-3Sb alloy was investigated. The wear tests were done on the alloys using pin on-disk equipment against a 4140 steel disc as counterpart under three different sliding velocities of 0.3, 0.6 and 1.2 ms-1 and four different loads of 5, 10, 20 and 40 N. The microstructural results showed that the new intermetallic phases (La5Sn3 and LaSnSb2) were formed with addition of La to the main alloy. Also, it was observed that the hardness of the Mg-3Al-3Sn-3Sb alloy was raised with increasing La addition. Furthermore, the tensile properties of the Mg-3Al-3Sn-3Sb alloy improved with rising La content at room and elevated temperature. The wear rates of the alloys increase with increasing of the sliding speed and load. In addition to this, the wear rate of the Mg-3Al-3Sn-3Sb alloy was found to be higher than that of the La content alloys for all test conditions.

The development of lightweight magnesium (Mg) alloys capable of operating at elevated temperatures of 200–300 °C and the ability of using high pressure die casting for high-volume manufacturing are the most advanced developments in manufacturing critical parts for internal combustion engines used in power tools. Here we report the microstructure and mechanical properties of a newly developed die-cast Mg–RE(La,Ce,Nd,Gd)–Al alloy capable of working at higher elevated temperatures of 200–300 °C. The new alloy delivers the yield strength of 94 MPa at 300 °C, which demonstrates a 42% increase over the benchmark AE44 high temperature die-cast Mg alloy. The new alloy also has good stiffness at elevated temperatures with its modulus only decreasing linearly by 13% from room temperature up to 300 °C. Thermal analysis shows a minor peak at 364.7 °C in the specific heat curve of the new alloy, indicating a good phase stability of the alloy up to 300 °C. Nd and Gd have more affinity to Al for the formation of the minority of divorced Al–RE(Nd,Gd) based compounds, and the stable Al-poor Mg12RE(La0.22Ce0.13Nd0.31Gd0.31)Zn0.39Al0.13 compound acts as the continuous inter-dendritic network, which contribute to the high mechanical performance and stability of the new die-cast Mg alloy at 200–300 °C.

The purpose of the present study is to determine the cause of failures of semisolid rheocast cylinder head covers of hypereutectic modified LM30 alloys. The covers, manufactured by rheocasting, a process that consists of the incorporation and homogeneous distribution of the reinforcements in semisolid metal (SSM) before die casting, were shot-peened after heat treatment to increase the fatigue resistance. However, these engine components failed during operation after a short service time. The major flaws were located by radiography. The microstructure was controlled by metallography. Significant interactions between shot peening and surface/subsurface contaminants were identified by surface morphology and fractography. The fatigue properties of hypereutectic alloys were investigated by a high-frequency vibrophore. It was identified that the failure was related to the cleanliness of SSM as well as the rheocasting process. Recommendations were given to prevent the recurrence of similar failures.

Aluminum alloys for high-pressure die casting (HPDC) usually contain sufficient quantities of dissolved iron to reduce die wear and soldering. Unfortunately, iron reduces ductility, making the product unsuitable for crash-resistant automotive components. Recent improvements in machine design and new alloys allow the production of high ductility, structural HPDC components. This paper details the chemical and metallurgical factors underlying this development .

The development of corrosion resistant steel for molten Al has always attracted the interests from die casting industry for several decades. In this paper, we reported the enhanced corrosion resistance in 750 °C molten Al of an alumina-forming austenitic steel (AFA) via deliberately producing oxide layer after different high-temperature oxidation processes. The results showed that the corrosion resistance against molten Al of the AFA was improved significantly due to the presence of a stable, compact and continuous oxides barrier, in comparison with H13 tool steel as well as unoxidized AFA without Al2O3 film. Apparently, the non-wetting α-Al2O3 film, which was formed after high-temperature oxidation, effectively protected the substrate from inner-diffusion and penetration of the molten Al. These findings provide one of cost-effective ways to improve the corrosion resistance of steels against molten Al.

Aluminum Silicon Alloy (Al-Si) is widely used in the industry because it has a good cast ability, good mechanical properties and good corrosion resistance. At its expense, many failures are caused by fatigue fracture. Fatigue fracture is caused by a dynamic load within a certain time or cycle. Nearly 90% of structural components damaged caused by fatigue fracture. To improve the mechanical properties of Al-Si alloys can be added Cu elements. In this study Al-10Si alloys added Cu elements with variations of 1, 3, 5 (wt.%) Through die casting process. The casting results are mechanical characterized by hardness test, tensile test and fatigue test. The microstructure was examined by optical microscope and SEM. The results showed that the addition of Cu elements up to 5 wt. % in Al-10Si increased hardness to 98 HRB and tensile strength to 245.23 MPa but decreased ductility from 3.1% to 2.4%. The results of fatigue test showed a significant increase in the number of cycles at 80MPa can reach 1.5 x 107 without fracture (fatigue endurance limit). The microstructure examination results confirmed the presence of CuAl2. The CuAl2 phase inhibits dislocation movement so that greater force for deformation and improve mechanical properties

High-strength alloys of Al-xZn-3Cu (x = 20, 30, 40 wt pct) are developed for die-casting process. The maximum tensile strength of the developed alloy is 435 MPa, with a stain to fracture of ~ 4 pct. Microstructural investigation shows that the grain size of α-Al gradually decreases and the area of the Zn-rich region increases as the amount of Zn increases. Local symmetry investigation reveals that the major phase of α-Al contains very fine nanoprecipitations of Zn phase (

The demand for producing essential cast parts and the design requirements for superior engineering performance have increased in recent years. Sand cores used in conventional aluminum cast parts are harmful to the environment, which limits their application. Utilizing water-soluble cores in the aluminum casting industry is expected to be an environmentally friendly approach due to recyclability of the salt cores. In this study, water-soluble salt cores were made from chloride- and/or carbonate-containing salts in various amounts. The salts were melted and cast into steel molds to obtain salt cores. The salt cores were subjected to three-point bending tests to determine their mechanical strength, the melting points were determined with thermal analyses, and the water solubility was measured at room temperature and 50 °C. A maximum bending strength of 17.19 MPa, a maximum melting point of 776 °C and a maximum water solubility of 89 g salt/100 ml water were obtained for the samples with compositions of 75% KCl–25% K2CO3 and 25% Na2CO3–75% K2CO3, respectively. Fractographs of the samples used in bending tests were taken by a still camera in macro mode, and from these fractured surfaces, scanning electron microscopy studies were performed. The X-ray diffraction pattern of the sample exhibiting optimal properties (28.3% Na2CO3 and 71.7% K2CO3) also showed that K2CO3, NaKCO3 and KNaCO3 phases were present in the structure, as expected. An actual casting process with aluminum die casting of an automotive part was also performed. The diecast aluminum part was subjected to a leak-proof test, and X-ray images were used to check for porosity in the part.

In this work, the development of AlZnMg(Cu) alloys was performed by thermodynamic simulations and experimental tests. With calculations, the solidification processes and phase compositions could be predicted. As secondary casting alloys, the selected compositions of AlZn4Mg3Cu(Fe) and AlZn5Mg4Cu have higher contents of alloying elements, such as iron and silicon, and were successfully processed with a cold-chamber die casting machine. In addition, an energy- and time-saving optimization of the material properties was performed by a modified heat treatment (T6*) with a total time of only 12 h. The alloys were evaluated based on the characterization of their mechanical properties and the analysis of their microstructures. In particular, the elimination of cost-intensive alloying elements and the application of a modified heat treatment method clearly show the potential of AlZnMg(Cu) die-cast alloys for future industrial use.

Soldering remains one of the most common defects in high pressure die casting (HPDC). It is most simply defined as aluminum stuck to the die surface. At ejection, the stuck aluminum gouges the casting resulting in dimensional and leaking defects. For nearly 50 years, a thermodynamics and kinetics understanding of soldering has been accepted while explicitly assuming that other mechanisms are not important. It will be shown that this thermodynamics and kinetics modeling approach cannot adequately explain three common observations in die casting foundries. First, soldering occurs much faster than the measured intermetallic growth rate based on diffusion couple experiments. Second, the alloys that are industrially observed to solder less form intermetallic phases quicker and dissolve the steel faster than alloys that solder more rapidly. Finally, the intermetallic layer is not strong enough to enable the buildup commonly observed on soldered dies. For these reasons, it is proposed that a new soldering modeling approach is required to gain a better understanding of the soldering mechanism and prevent the soldering defect in die casting.

Si ranging from 0.2 mass% to 2.0 mass% was added to Al-5%Mg alloy (5182) and strip was cast by a vertical type high-speed twin-roll caster at a speed of 80 m/min. The as-cast strip was cold-rolled down to 1 mm thickness and annealed. The mechanical properties were investigated using cup tests and tension tests. The limiting draw ratio (LDR) of the 5182 alloy was 2.0 and the LDR became smaller as the Si content increased. When the Si content was 2.0 mass%, the LDR was 1.8, which shows that Si-added 5182 can be used for sheet forming, if the Si content is less than 2.0 mass%. The tensile strength and elongation were almost constant when the Si content was less than 1 mass%, but decreased at 2.0 mass% Si. However, the elongation was greater than 20% at 2.0 mass% Si. For die casting, 2.0 mass% Si was determined as the appropriate content from the results of the tension tests. When the Si content is in the range from 1.0 mass% to 2.0 mass%, then the Si added Al-5%Mg has the ability to be used for both die casting and sheet forming.

The effect of thermal exposure at 350 °C for 200 h on microstructure and mechanical properties was investigated for Al−Si−Cu−Ni−Mg alloy, which was produced by permanent mold casting (PMC) and high pressure die casting (HPDC). The SEM and IPP software were used to characterize the morphology of Si phase in the studied alloys. The results show that the thermal exposure provokes spheroidization and coarsening of eutectic Si particles. The ultimate tensile strength of the HPDC alloy after thermal exposure is higher than that of the PMC alloy at room temperature. However, the TEPMC and TEHPDC alloys have similar tensile strength around 67 MPa at 350 °C. Due to the coarsening of eutectic Si, the TEPMC alloy exhibits better creep resistance than the TEHPDC alloy under studied creep conditions. Therefore, the alloys with small size of eutectic Si are not suitably used at 350 °C.

Die soldering is a sticking phenomenon between molten aluminum with the surface of steel die in the die casting process, which results in damage to the cast products and l the steel die. In this research, two die materials, H13 and Cr-Mo-V steels were used. Those dies were then treated by two process variables, shot pinning and nitriding-shot pinning. To simulate the die casting process, the samples were dipped into molten Aluminum-Si alloy, ADC12 at 680oC for 30, 300, and 1800 seconds. Characterizations were focused on the surface of the steel, which includes microstructure observation by a microscope, microhardness profile, compound identification, and weight loss measurements. It was found that H13 steel and Cr-Mo-V steel treated by nitriding–shot pinning have higher hardness up to 100% and thinner intermetallic layer. On H13 steel, the compact layer thickness decreased from 19 μm to 17 μm and from 96 μm to 80 μm for the broken layer. Similar trends occurred for Cr-Mo-V steel, where the thickness of the compact layer and broken layer decreased from 38 μm to 19 μm and 119 μm to 45 μm respectively. These results indicate that H13 and Cr-Mo-V steels that were treated by nitriding–shot pinning have a better resistance to die soldering.

The hot chamber die casting process is capable of producing castings of superior mechanical properties and internal integrity. However, this process cannot be used for die casting of aluminum alloys because the molten aluminum erodes ferrous alloy tooling such as the gooseneck. Ceramic gooseneck was tested, but was not accepted commercially. This work evaluates the feasibility of using refractory metals for the tooling of the hot chamber die casting process. Experiments were performed to measure the weight loss of selected materials in molten aluminum at die casting temperatures. Refractory metals with excellent aluminum erosion resistance were selected and used for making gooseneck and nozzle. These components were installed in a hot chamber die casting machine. The world’s first hot chamber die casting machine equipped with refractory metal tooling is now running at Purdue University for making aluminum alloy castings.

Both the mechanical properties and microstructure of die-casting ADC12 + x(La+Yb) alloy (x = 0, 0.3 wt.%, 0.6 wt.%, 0.9 wt.%) were investigated. It was found that the main compounds of the ADC12 ma...

Magnesium alloys are commonly used to produce lightweight parts. While most magnesium alloys exhibit low thermal conductivities, high thermal conductivities are needed for electronic devices. In this study, we attempted to develop new magnesium casting alloys with high thermal conductivities. The MgZnSiCa alloy compositions were chosen using CALPHAD (CALculation of PHAse Diagrams) calculations, and alloy samples were prepared. The fluidity and hot-tearing resistance were measured. The results indicated that these properties were similar to those of AZ91 alloy. Tensile tests showed that high-pressure die casting could produce MgZnSiCa alloys possessing mechanical properties 1.5–3 times higher than those produced via sand casting. The alloy thermal conductivity was 126 W/mK at room temperature. The corrosion rates of the as-cast samples in NaCl/water solutions were two times higher than that of AZ91. Keywords: Magnesium alloy, Thermal conductivity, Phase composition, Corrosion rate, Sand casting, High-pressure die casting

High pressure die casting Mg-Al-RE alloy has an intrinsic and macroscopic gradient structure regarding the grain size and the area fraction of second phase along the depth direction. Such gradient structure exhibits incompatible but continuous mechanical properties in regions of different depth from surface during uniaxial tension. An extra strain hardening and a higher strength are thus produced. The unique mechanical behaviors originate from the generation and accumulation of geometrically necessary dislocations promoted by the strain gradient.

Direct water cooling (DWC) application with the lost foam casting (LFC) process was inspired by the ablation casting technique. Ablation casting is designed to combine the controlled filling property of sand mold casting and the rapid cooling of the high-pressure die casting. Briefly, in this method, sand casting is followed by the removal of the mold by water spray and cooling of the part within a short time. The use of special water-soluble inorganic binders facilitates the mold breakdown. However, due to no use of binder materials in the LFC method, the DWC process may become more effective. In this study, similar cooling techniques were applied to the lost foam castings of A356 alloy by two techniques. In the first one, cooling was achieved by tipping the mold content over into a container with a sufficient amount of water after the casting process. The second process was carried out by pouring a sufficient amount of water onto the mold following the casting process. These two developed methods were named as “quench casting” and “splash casting,” respectively. It was seen that both methods changed the traditional casting microstructure and properties considerably. A serious decrement in secondary dendritic arm spacing with accompanying modification of the eutectic silicon was observed for the specimens produced via both methods. Hardness values increased significantly, and the results indicate that splash casting is preferable than quench casting because it exhibits better and more stable properties.

A die to estimate the thickness of the thinnest fin of a heat sink made by die casting aluminum alloys is proposed. The die consists of a taper-off thin fin and a cooling area. It was shown that this die can be used to estimate the smallest fin thickness of different aluminum alloys.

The results of a comparative research into the corrosion resistance of an aluminum matrix composite material produced by the oxygen lancing of a prehydrogenated aluminum alloy melt based on Al–Si–Fe with an iron content of over 1.0% and Al–7% Si alloy with an iron content of up to 0.3% modified by ligature 5Al–Ti for 2% are shown. The aluminum-alloy corrosion was conditioned by the film discontinuity of the oxide on some phases, primarily Al5SiFe. The composite and reference alloy-sample couples with a diameter of 15 mm and a length of 50 mm were put to the test in a 7% solution of NaCl salt fog in SFC-1 chamber on suspension brackets at a temperature of 22°C for 300 h. The results show the mass loss close values of the samples, despite the significantly higher iron content in the composite, because particles 100–200 nm in size formed in the melt by lancing are deposited on the composite phase boundaries, reducing the interaction surface area with the corrosive environment. The researched composite material can be recommended as a corrosion-resistant alternative to alloys with elevated iron content, which are used for high pressure die casting (HPDC).

A practical bimetallic casting consisting of aluminum matrix and cast iron inserts was manufactured via high pressure die casting (HPDC) process. Different surface treatment methods of the cast iron inserts, including salt membrane plating and electrogalvanizing, were adopted to improve the bonding quality of bimetallic castings. Microstructure characterization on the bonding interface was conducted at different locations of bimetallic castings. Results indicate that compounds with flawless and continuously metallurgical bonding interface can be successfully fabricated by the HPDC process with the zinc rack plating treatment on the surface of cast iron inserts which results in a dense zinc coating with an average thickness of 8 μm. The melt flow speed and heat transition during solidification of the HPDC process are two key factors in determining the bonding integrity of bimetallic castings. With the dissolution and diffusion of the very thin zinc coating during solidification, there is no obvious aggregation of zinc element at the metallurgical bonding interface. Instead, a reaction layer with an irregular tongue-like morphology is formed with an average thickness of approximately 1 μm while it mainly consists of intermetallic phases Al60Cu30Fe10 and Al2FeSi, etc.

The focus of this study is to improve the clinching ability of an aluminum die casting alloy with a sheet metal by local annealing in order to clinch them in a process-safe manner. For this purpose, the influence of three different heating strategies (heating plate, resistance heating and inductive heating) on the generation of clinching joints are investigated. Furthermore, the strategies are compared with regard to process time, joining point formation and bonding strength. Finally, the different heating strategies were evaluated and the most promising process parameters were identified.