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Magnesium alloys are still attractive materials for applications that necessitate light weight due to their low density, moderate strength, and good corrosion resistance. AZ91 is one of the widely applied magnesium alloys due to its very good castability and strength. However, one of the drawbacks of magnesium alloys is the low elastic modulus. So, reinforcing AZ91 with carbon short fibers with the aim of further increasing the strength and improving the elastic modulus is investigated in this study. Squeeze cast AZ91-23 vol.% carbon short carbon (AZ91-C) and the unreinforced AZ91 are deeply examined by tensile testing at different temperatures (20, 100, 150, 200, 250, and 300 °C). Tensile stress–strain curves are measured and the tensile parameters (yield stress, ultimate tensile strength and strain) are defined and presented against the test temperature. Yield stress of AZ91 at 20 °C (109 MPa) is doubled (226 MPa) in the reinforced AZ91-C. Yield stress is found to slightly decrease with increasing the test temperature. Ultimate tensile strength of AZ91 at 20 °C (198 MPa) is increased (262 MPa) in the reinforced AZ91-C. The improvement of the ultimate tensile strength due to reinforcing increases with increasing the test temperature. Flow curves are determined and described by a modified Mecking–Kocks relationship and the flow parameters are determined and described as a function of the test temperature. Microstructure investigation was undertaken of the fractured tensile specimens at the grain boundaries rich in eutectic structure formed at the grain boundaries. Mixed brittle/ductile fracture mode is detected on the fracture surface of unreinforced AZ91, while the SEM investigations show matrix/carbon fiber detachment and fiber fracture as main fracture modes.

Dendrite arm spacing (DAS) plays a vital role in determining mechanical properties of aluminum casting composites. In this study, the effects of three different methods of gravity sand casting, squeeze casting, and semi-solid compo-casting with different electromagnetic stirring currents and times on the microstructural morphology of A356-Al2O3 composites were investigated. In order to investigate effects of shear forces on the formation of the globular-like structure, samples with different stirring electric current and times were produced by compo-casting in semi-solid state and analyzed. Optical emission microscopy was used to study the microstructure and DAS of nanocomposites. Quantitative analysis of microstructure was performed by utilizing an image analysis system. In this study, the optimum temperature for composite fabrication for this type of composite was calculated to obtain the most appropriate morphology and size of the microstructure. Also, the appropriate time to keep this composite at this temperature was obtained, and finally the relevant microstructures were fully discussed.

The present investigation deals with development of AA2219 composites with different weight fractions of Cerium oxide (CeO2) reinforcement and characterizing the microstructure and mechanical properties thereof. XRD and SEM micrograph confirm the presence of CeO2 particles and Al2Cu precipitate. The grain size of 0, 0.5, 1.0, 1.5 and 2 wt% CeO2 composites are 483, 453, 411, 362 and 328 μm, respectively. Addition of CeO2 significantly reduces the dendritic morphology and refines the α-Al grain structure. 2 wt% CeO2 addition has yielded the maximum hardness of 124 HV and yield strength of 87 MPa in all the composites developed. Additionally, the developed composites were evaluated by examining the wear characteristics with the co-efficient of friction (COF) and the specific wear rate. In this study, Taguchi's L25 orthogonal array was used to optimize the parameters like reinforcement fraction, load and sliding distance. Signal-to-noise ratio (S/N ratio) and analysis of variance (ANOVA) are used to obtain the parameters highly influencing the wear behaviour. Adhesive wear is exhibited by ploughing at lower loads and delamination is observed with increasing load. Deep shallow ploughs with embarked abrasion are observed at higher loads.

Metal matrix composite has been developed to improve mechanical properties for the automotive component application. One crucial factor in achieving excellent mechanical properties is improving the properties of the aluminum matrix of composite by the heat treatment process. The mechanical properties of Al-Mg-Si matrix composites alloyed with Zn and reinforced with 5% SiC and 5%Gr particle were examined after the heat treatment process. The aluminum matrix is melted inside the crucible furnace at 850 °C and is added with SiC/Gr particle, followed by stirring at 7500 rpm to optimize the mixing of the composite. Then, the composite is poured into the preheated mold at 300 °C and then squeezed with 30 MPa of pressure. The heat treatment process consists of three steps; solution treatment, quenching, and artificial aging. The aging process is conducted with variation of temperature (140 °C, 180 °C and 200 °C) and holding time (2, 4, and 6 hours). The test results show that the mechanical properties of aluminum matrix composite tend to increase after the heat treatment process. The optimum mechanical properties are achieved at the aging temperature of 200 °C for 6 hours, with the hardness value of 60.3 HRA and the impact value of 0.112 Joule/mm2.

The development of aluminium composite with the inclusion of advanced materials is a continuous research process due to the increasing industrial demand for advanced hybrid materials. To cater for this need, this research work focuses on the development of Al 7075 alloy reinforced with TiB2 and graphene and on the evaluation of its strengthening mechanism. Two different modes of improving the strength of the hybrid composite have been followed; one is by the inclusion of graphene at three levels of 0.1, 0.2 and 0.3%, and another by the processing route, squeeze casting technique by compression of the molten hybrid composite slurry before casting. The microstructure and characterisation of the composite material are examined and analysed with the help of XRD, SEM, EDAX and chemical spectroscopy. A microstructure evaluation is employed to justify the homogenous dispersal and the existence of reinforced particles. A tensile test is conducted at room temperature and high temperature environments to assess the tensile strength. The research outcome affirms that a significant improvement in tensile and hardness has been noted in comparison with base alloy. The fracture-morphology results affirm the change in fracture mode from brittle to ductile when the tensile testing environment changes from room temperature to high temperature. Finally, the dispersion strengthening mechanism is validated with an empirical approach.

Al-8Zn-2Mg-1.5Cu-0.15Sc-0.15Zr alloy with high-strength performance as well as good castability has been developed. In this study, effects of electromagnetic stirring melt treatment (ESMT) on microstructure and mechanical properties of the alloy in the squeeze casting process were investigated. The results show that solidification structure and mechanical properties are significantly improved by ESMT; compared with the conventional squeeze casting, the average grain size decreases from 112 μm without ESMT to 53 μm with ESMT. Meanwhile coarse primary Al3(Sc, Zr) particles unavoidably occurred in cases without ESMT disappear, and segregation degree of the main elements of Zn, Mg, Cu are greatly alleviated; the tensile strength increases from 590 MPa to 610 MPa, and the elongation increases from 9% to 11%. The structure refinement and homogenization should owe to uniform temperature and composition distribution by ESMT under squeeze casting with rapid solidification.

In this study, AZ91/23 vol.% short carbon fiber composite was produced by a squeeze casting technique using a cylindrical pre-form of treated carbon fibers, in which the fibers are randomly oriented in the horizontal plane. Cylindrical specimens (height = 9 mm and diameter = 6 mm) were machined from the as-cast AZ91 matrix and its composite. The full behavior of the produced composite was studied through the test specimens machined in two directions, namely parallel to the reinforced plane (in the radial direction of the cast cylinder) and normal to the reinforced plane (in the axial direction of the cast composite). The microstructures of the produced composite specimens were investigated using SEM equipped with EDS analysis. Density, hardness, compressive, and wear behavior were also investigated. For comparison, the AZ91 matrix was evaluated as a reference. The microstructure of the produced AZ91 matrix alloy and its composite revealed dense materials without casting defects. Both composite specimens show improvement in hardness, compressive strength, and wear properties over the AZ91 matrix. The compressive and wear properties are more fiber orientation-dependent than the hardness results. The parallel composite specimen depicts the highest compressive properties in terms of yield compressive strength (311 MPa) and ultimate compressive strength (419 MPa), compared to that shown by the AZ91 matrix and the normal composite specimen. This improvement in compressive strength was at the expense of ductility. The parallel composite specimen shows the lowest ductility (R = 3.8%), compared to that given by the normal composite specimen (R = 7.1) and the AZ91 matrix alloy (R = 13.6). The wear testing results showed that at the highest wear load of 5 N, the material weight loss of the parallel composite specimen decreases by 44% and 64% compared to the AZ91 matrix and the normal composite specimen, respectively.

Composite mold samples used in squeeze casting was fabricated by plasma spraying with 5CrMnMo and 3YSZ, which was shown high bonding strength and good thermal shock resistance. The best parameters with transition coat were explored by mechanical analyses. As results, the transition layer structure made of 75 percent NiCoCrAlY powders showed bonding strength was higher to 34.35MPa and that thermal cycles were up to 46.8 times. The effect of the transition layer was analyzed by microstructures and the failure mechanism of the coating material with a transition layer was discussed. The conclusion was that the physical mismatch and thermodynamic mismatch between the matrix and ceramic layers were the main cause of the failure.

The microstructure, mechanical properties and flame resistance behavior of the AZ91−1Ce alloys with different Ca additions were firstly investigated. Then, the effect of processing parameters, including applied pressures and rotation speeds, on the microstructure and mechanical properties of the rheo-squeeze casting AZ91−1Ce−2Ca alloy was studied. The results indicate that with the increase of Ca content, the microstructure is refined and the flame resistance of the AZ91−1Ce−xCa alloys increases. But when the Ca content exceeds 1 wt.%, with the Ca content increasing, the mechanical properties of the AZ91−1Ce−xCa alloys reduce rapidly. For rheo-squeeze casting process, the increase of applied pressure and rotation speed can both bring about significant refinement in the microstructure of the AZ91−1Ce−2Ca alloy and reduction of the porosity, so the mechanical properties increase. Compared to conventional casting, the AZ91−1Ce alloy with the addition of 2 wt.% Ca by rheo-squeeze casting not only guarantees the oxidation resistance (801 °C), but also improves mechanical properties.

In this article, a new metal–matrix composite was developed with fly ash (an industrial waste from petroleum industries) as reinforcement and aluminium metal (A357) as a matrix by squeeze casting technique. This study was concentrated on the processing of the composites with different weight percentage ranging from 0 to 10 wt.% in a step of 2.5 each and also reported the erosion wear behaviour. Solid particle erosion of A357/fly ash composites was carried out with four velocities (48, 70, 82 and 109 m/s), at impact angles (30°, 45°, 60° and 90°), with silica as an abrasive particle at ambient temperature. The eroded surfaces were analysed by scanning electron microscopy. The results revealed that the impact velocity and impingement angle both affected the erosion wear behaviour of the composites. The erosion rate rises with an increase in impact velocity, irrespective of the change in impingement angle and weight percentage of the fly ash. The erosion mechanism studied for the composites is microploughing and microcutting.

Aluminium alloys are having lightweight, high strength, good corrosive resistance, and toughness. In this paper, A7075/B4C/SiC Hybrid Composites fabricated with different wt. % of reinforcement materials by using stir and squeeze casting process. The SEM Microstructure have shown that uniform distribution of reinforcement particles in the A7075 matrix reinforced with 1 % wt. % B4C and 1 % wt. % SiC. The Mechanical properties of A7075/B4C/SiC Hybrid Composites were studied Composite A7075/B4C/SiC reinforced with 1 % wt. B4C and 1 % wt. SiC has shown more compressive and tensile strength compared to base alloy. The compressive strength of the composite increased 39.73 % and the tensile strength is increased 36.67 % compared to base alloy. From the dry sliding wear studies, the Composite with 1 B4C wt. % have shown less weight loss and coefficient of friction at all conditions due to the uniform distribution of the micro-particles within the matrix surfaces. Worn surface morphology has revealed that severe wear of A7075 base alloy became mild wear by preparing composite with 1 % wt. SiC, 0.5 wt. % B4C and then mild wear became less wear with shallow grooves by increasing reinforcement weight percentage of B4C from 0.5 to 1.

The squeeze casting process for an AlSi9Mg aluminum alloy flywheel housing component was numerically simulated using the ProCAST software, and orthogonal simulation tests were designed according to the L16 (4) 5 orthogonal test table to investigate the alloy melt flow rule under four factors and four levels each of the pouring temperature, mold temperature, pressure holding time and specific pressure, as well as the distributions of the temperature fields, stress fields and defects. The results showed that the flywheel housing castings in all 16 test groups were fully filled, and the thinner regions solidified more quickly than the thicker regions. Hot spots were predicted at the mounting ports and the convex platform, which could be relieved by adding a local loading device. Due to the different constraints on the cylinder surface and the lower end surface, the solidification was inconsistent, the equivalent stress at the corner junction was larger, and the castings with longer pressure holding time and lower mold temperature had larger average equivalent stress. Shrinkage cavities were mainly predicted at mounting ports, the cylindrical convex platform, the peripheral overflow groove and the corner junctions, and there was also a small defect region at the edge of the upper end face in some test groups.

A challenge for the research and industrial community is to develop lightweight wrought Mg-based alloys that exhibit high strength and good ductility. To address this challenge, Mg-3Sn-2Al (TA32) alloy was produced by the squeeze casting process followed by hot rolling (HR). To improve its ductility, the hot-rolled alloy was annealed (HRA). HR and HRA samples were subjected to microstructural, composition, textural, and mechanical property analysis. The HR sheet exhibited high strength with 0.2% proof stress (PS) of 274 MPa and ultimate tensile strength (UTS) of 390 MPa, as well as reasonable ductility (12%) along the rolling direction, one of the highest values for Mg alloys. HRA sheet showed a moderate reduction in strength with a 0.2% PS of 250 MPa and UTS of 365 MPa, but an improvement in ductility (19%). The excellent properties of this alloy can be attributed to the synergistic effects of grain refinement, solid-solution strengthening by Al and Sn atoms, and uniform distribution of fine Mg2Sn particles.

Among non-ferrous materials, aluminium and its alloys are one of the challenging materials having high structural characteristic, superior tribological and mechanical properties and used for the ty...

Nowadays, Squeeze casting is considered as a convenient process for developing quality piston components. In this paper, casting methods such as squeeze casting and die casting techniques are used ...

Squeeze casting is one of the simplest processes of manufacturing of composite materials and it attains higher advantages of low material processing cost, easy handling of material, size, design and good stability of matrix structure. LM24 aluminium alloy reinforced with silicon carbide (SiC) and coconut shell ash (CSA) were used to prepare the composite. LM24 alloy had wide engineering applications, wherein the addition of SiC enhances the wear resistance and CSA particles offer significant technical and economic benefits. In the present study, the composite samples were prepared based on Taguchi experimental conditions L16 (4-levels and 5- parameters) through squeeze casting method. From the experimental results, percentage of reinforcement and squeeze pressure were most influential parameters on impact strength. The optimum casting condition was obtained by using Taguchi optimization. From microstructural study, applying high level of squeeze pressure improved the uniform dispersion, good bonding between the matrix and reinforcement. Also, 25% of impact strength was improved the composite using Taguchi optimum conditions compared than conventional alloys. Higher squeeze pressure seen to have refined dendritic structure with uniform distribution of reinforcement materials in the aluminium matrix.

High strength and less weight materials are required for industrial expectations with low cost for their working process. Nonferrous materials are less in weight but the strength of the material is less compared to ferrous materials. Ferrous materials having high strength but it have more weight when compared to nonferrous materials. To make the combination of ferrous and non-ferrous materials properties are increased by its strength. The weight of the material is to be reduced but its mechanical and metallurgical properties have to be improved. The non-ferrous material like aluminium has less weight and the ferrous material like steel has high strength. These two materials make a combination of considerable weight providing high strength. The steel wire and steel mesh are reinforced in aluminium alloy by squeeze casting and gravity die casting method. After the process has been done testing methods has been processed on the materials to check the mechanical and metallurgical properties. Were aluminium (LM6) and steel wires of 1 mm diameter were used as the reinforcement increased the mechanical strength and metallurgical properties.

Segregation can seriously damage the mechanical properties of the aluminum alloys. 6061 aluminum alloy wheel spokes were prepared by squeeze casting. To investigate the formation mechanism of segregation, the microstructure of the alloy was observed using scanning electron microscopy, energy dispersive spectrometry, X-ray diffraction and electron microprobe analysis methods. The Gibbs energy of each phase during solidification was calculated by JMatPro. Results show that the segregation phases in the R-joint of the wheel spokes are mainly composed of Mg2Si, β-AlFeSi and Al5Cu2Mg8Si6 intermetallics. During the solidification of the 6061 aluminum alloy wheels, Mg2Si and α-AlFeSi phases precipitate in the mushy zone at first. With the decrease of temperature, α-AlFeSi transforms into β-AlFeSi, while Al5Cu2Mg8Si6 precipitates from the solid-state aluminum alloy after solidification. Segregation at the R-joint of wheel spokes is mainly caused by insufficient cooling, so the cooling during alloy solidification should be enhanced to avoid segregation.

Particulates strengthened aluminium hybrid intermixtures is formed using squeeze casting method by varying weight percentage (2%, 4% and 6%) of SiC and keeping 2% WC constant. Pin on disc of wear test has been used to investigate the wear properties and coefficient of friction of synthesized aluminium hybrid composites under dry sliding conditions by varying its load and sliding speed. The sliding distance had been maintained constant. The structural features of the synthesized composites and its morphological properties were studied by Scanning Electron Microscope (SEM). Wear rate of synthesized mixtures is significantly increased at all affixed loads. SEM images of the worn out surfaces revealed that particulates micro fracture was the predominant mechanism associated with abrasive wear. Micro hardness of Aluminium hybrid been significantly increased due to incorporation of stronger and stiffer reinforced particles and it leads to low wear with high friction coefficient developed hybrid compared with monolithic material.

This research work deals with an investigational study on the temperature developed while cylindrical grinding of Al7075/RHA composite. The Al7075 base material is reinforced with rice husk ash (RHA) particles through squeeze casting methodology wherein the amount of RHA in Al7075 matrix is varied as 5, 10 and 15% in weight. The parameters that are taken into consideration for grinding study are RHA %, table feed and depth of cut each at three levels. The experiment is designed based on Taguchi design of experiments and the output response is temperature. The results revels that the RHA %, table feed and depth of cut have inverse effect over temperature. Analysis of Variance (ANOVA) results confirmed that the grinding temperature has greatly affected by the amount of reinforcement present in the matrix. The developed regression equation has the higher ability to forecast the output with minimal deviation.

In this study, the heat treatment process of a high-chromium cast iron (HCCI) alloy prepared via 128 MPa squeeze casting at different subcritical quenching temperatures was investigated. The results showed that subcritical heat treatment can change the martensite content, the carbide type and size of the squeeze casting HCCI microstructure. Furthermore, it was revealed that the subcritical quenching heat treatment can improve the hardness of the liquid-forged HCCIs. When the quenching temperature increased from 500 °C to 530 °C, the hardness of the alloy increased significantly, reaching a maximum value of 57 HRC. Thereafter, if the temperature continued to rise to 630 °C, the hardness decreased rapidly. For impact toughness, when the quenching temperature was 500 °C, the toughness of alloy increased by 0.9 J/cm2 than that of the no heat treatment group. If the quenching temperature continued to increase, the toughness was reduced. Taking hardness and toughness into account, the microstructure evolution diagram of the optimal process-500 °C subcritical quenching process was established, various characterisation techniques were used to gain insights into the optimal heat treatment process. Compared with high temperature heat treatment, subcritical heat treatment can improve the performance of the HCCI alloy and reduce costs.

The creep behavior of a binary Mg-15 wt.% Gd alloy was investigated over the temperature range from 523 K to 743 K, i.e., in both the single-phase region (the hexagonal close-packed solid solution of Gd in Mg) and the two-phase region (the solid solution plus Mg5Gd precipitates). The alloy was prepared by the squeeze casting technique. In the higher temperature range, at 723 and 743 K, the specimens were solution treated by in situ annealing prior to testing. At the temperature of 673 K and below, the alloy was tested in the cast state. In the higher temperature range, the behavior was interpreted in terms of the viscous glide, where the dislocation motion was constrained by the presence of solute atmospheres. The dislocation motion was controlled by the rate of the cross slip from the basal to the prismatic planes. At the temperatures of 623 K and 673 K, the creep behavior was rationalized by introducing the threshold stress concept. At the temperatures of 523 K and 573 K, the stresses required to achieve experimentally measurable creep rates were such that dislocations broke away from the atmospheres of foreign atoms. Comparison with a series of magnesium alloys prepared by squeeze casting and creep-tested by the same technique showed that gadolinium can be a favorable creep-resistance enhancing element.

In the current study, microstructure and interfacial analysis of Al–Si–Cu/Al2O3 composite were investigated. Alumina was added in different fractions to study their effect on the microstructure. The distribution of the particles inside the Al–Si–Cu matrix and the reactions at the interface were developed using optical, SEM, XRD and EDS. The microstructures of the composites revealed a uniform distribution of the Al2O3 particle. The analysis of the interface between the matrix alloy and the Al2O3 particles indicated the presence of wetting agent of MgAl2O4 at the interface between the particles and the matrix. Moreover there is no particle agglomeration. The addition of Al2O3 particles into Al–Si–Cu alloy led to a reduction in the time required to attain peak hardness during aging and enhancing the hardness. Also, the wear resistances of Al–Si–Cu alloy based composites were significantly improved with the addition of Al2O3 particles.

The squeeze casting process blends the features of casting, forging, and also helps in achieving better manufacturing abilities; attain smooth uniform surface, high productivity, superior mechanica...

In this study, a step die was made by P20 steel for squeeze casting aluminium alloy A380 with five different section thicknesses of 2, 4, 8, 12, and 20 mm under an applied pressure of 90 MPa. K-typ...

The current study investigated the relationship between the process settings and in-die conditions to understand the transitions between the different filling stages and the final pressure settings in indirect squeeze casting. A pressure sensor was placed in the die cavity to indirectly measure the evolution of pressure over time and monitor the filling process to study the in-die conditions. The pressure–time profile was analysed, and the maximum pressure and acceleration of the pressure were investigated empirically. The main conclusion of this paper is that the use of increasing intensification pressures is positive for the casting soundness. However, it must be stressed that there is a strong effect from the intensification pressure on the acceleration that has a far more reaching influence than the actual speed setting. A direct practical outcome is that a high intensification pressure has a more substantial effect than the second stage fill speed. This translates directly to a possibility of reducing the second stage fill speed to stabilise the fill front. Furthermore, this also pinpoints the need for improvements in hydraulics system designs to decouple the intensification pressure from the filling piston motion control.

Magnesium matrix composites are considered a desired solution for lightweight applications. As an attractive thermal management material, diamond particle-reinforced Mg matrix (Mg/diamond) composites generally exhibit thermal conductivities lower than expected. To exploit the potential of heat conduction, a combination of Cr coating on diamond particles and squeeze casting was used to prepare Mg/diamond (Cr) composites. The thickness of the Cr coating under different coating processes (950 °C/30 min, 950 °C/60 min, 950 °C/90 min, 1000 °C/30 min, and 1050 °C/30 min) was measured by FIB-SEM to be 1.09–2.95 μm. The thermal conductivity (TC) of the Mg/diamond composites firstly increased and then decreased, while the coefficient of thermal expansion (CTE) of Mg/diamond (Cr) composite firstly decreased and then increased with the increase in Cr coating thickness. The composite exhibited the maximum TC of 202.42 W/(m·K) with a 1.20 μm Cr coating layer, while a minimum CTE of 5.82 × 10−6/K was recorded with a coating thickness of 2.50 μm. The results clearly manifest the effect of Cr layer thickness on the TC and CTE of Mg/diamond composites.

The paper deals with processing of material in semisolid state by the technology of semisolid squeeze casting. The investigated material was a subeutectic aluminium alloy AlSi7Mg0.3. The influence of various preparation meth-ods of batch material on the structure after processing by this technology was studied. Alloy AlSi7Mg0.3 was pre-pared as gravity cast, inoculated, heat treated and by technology of direct squeeze casting. In article is assessed microstructure of castings before and after processing by technology of semisolid squeeze casting. The shape and distribution of eutectic silicon was observed. The shape and the distribution of alpha phase formations has an im-pact on whether micro-volumes of molten eutectic will be closed in alpha phase or will be segregated along the boundaries of alpha phase formations. It was observed the partial inheritance in microstructure. Also the segrega-tion in surface layer was observed.

In the present work, a step die was made by P20 steel for squeeze casting magnesium alloy AZ91 with five different section thicknesses of 2, 4, 8, 12, and 20 mm under an applied pressure of 60MPa. ...

Magnesium alloys have gained increasing attention for biomedical applications due to their biocompatibility and the biodegradability. Hydroxyapatite (HA) is known to be a highly bioactive because of its similar chemical and crystallographic structures to bone. Therefore, HA is believed to be a potential ceramic material for the fabrication of Mg based composites, to combine the advantages of both Mg and HA. But, in general, the composites known to be more susceptible to corrosion attack than the matrix alloy. Hence, in the present work, Sn is used as an alloying element to evaluate its effect on mechanical as well as corrosion properties of Mg/HA composites. Mg with 5 wt% HA and Mg-1 wt% Sn-5 wt% HA composites were prepared separately by stir assisted squeeze casting route. The phase analysis and microstructure were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM) coupled with energy dispersive spectroscopy (EDS) respectively. Mechanical properties were evaluated by conducting the compression and micro hardness tests. Corrosion properties of as-cast composites were studied by linear polarization, Tafel and electrochemical impedance spectroscopy (EIS) techniques. The results of both XRD and SEM-EDS revealed that the main constitutional phases of as-cast Mg/HA composites were α-Mg and HA whereas, in Mg-Sn/HA composites, the phase Mg2Sn was observed along with fine distribution of HA particles. In both the cases, no interfacial reactions observed. The yield strength, ultimate compression strength and hardness were found to be increased with the addition of Sn in Mg/HA composites. Furthermore, the addition of Sn also played an important role in increasing the corrosion resistance of the Mg/HA composites which was attributed the refinement of grain size and the formation of Mg2Sn phase along the grain boundaries. Hence, it was concluded that the addition of Sn improves both mechanical and corrosion properties of Mg/HA composites.

High-strength aluminum alloy with large-scale and thin-walled complex castings have broad application prospects in aerospace, weapons, electronics, defense and military industries. However, due to the uneven thickness of the plate, the casting defects are inevitable by the ordinary casting method, and it is impossible to accurately control the shape and performance of the casting in the casting process. Previous studies have found that the semi-solid rheological extrusion casting technology with short process and near-end type can help solve this technical problem. Therefore, this paper studies the semi-solid rheological extrusion casting process of thin-walled complex casting of ZL114A aluminum alloy. The combination of numerical simulation and experimental research is used to simulate and optimize the filling and solidification process of thin-walled specimens. Based on this, a semi-solid rheological extrusion casting test was conducted. The result showed that, (1) The optimized model can well reflect the filling and solidification process under different rheological extrusion casting parameters, and obtain defect-free castings through process optimization. (2) The thin-walled parts of the thin plate casting produced by semi-solid rheology extrusion have excellent mechanical property and ductility.

LM25 aluminum alloy reinforced with 10 wt% of TiB2, WC, and ZrO2 were squeeze cast to investigate the effect of T6 heat treatment on tribo-mechanical properties. Among all, WC-reinforced composite achieved superior mechanical properties at the aging time of 8 h. Microstructural examination performed on all composites and alloy concluded that the presence of WC in T6 LM25 caused reduction of α-Al dendrite size, exhibiting superior properties for this composite. X-ray diffraction analysis conducted on alloy and WC-reinforced superior composite revealed formations of phases, which improved their mechanical properties. Energy-dispersive X-ray spectroscopy analysis quantified the actual intensity of WC presence in the superior composite along with its other constituents. Response surface methodology model developed for wear test of the superior composite involves parametric range like applied load (10–50 N), sliding velocity (1–4 m/s), and sliding distance (500–2500 m). Analysis of variance along with regression analysis proved that, statistical analytical model developed good relationship between the actual wear rate and process parameters. Response surface plots represented the linearly increasing wear trend with respect to load and sliding distance. Wear rate dropped initially and raised later on along with velocity. Scanning electron microscopy exhibited the surface deformation prevailing on the composite surface at high load.

Novel interpenetrating phase composites (IPCs) were produced by infiltrating ZA8 alloy into sintered 304 stainless steel fiber preforms through squeeze casting. Microstructural characteristics and ...

The present investigation deals with the microstructural modification following the Bi + Sr additions to the squeeze-cast AZ91 alloy and its effect on impression creep response. The Bi + Sr additio...

Hybrid metal matrix composites (MMCs) were prepared with AA 5754 as matrix and B4C (fixed with 1 wt.% and average particle size as 25 μm) and Al2O3 reinforcements (varied from 0.5 to 2 wt. % with the interval of 0.5 and average particle size as 50 nm) using Rheo-squeeze casting process. Microstructure images were taken to observe the uniform distribution of reinforcement particles on the matrix alloy. The tensile strength for AA 5754 with 1 wt.% B4C and 2 wt.% Al2O3 hybrid composite showed higher value compared to base alloy and other composites. The wt. % of Al2O3 in the composite is increased to 2 %, the tensile strength and compressive strength were also increased due to combined Rheo-squeeze casting. AA 5754 reinforced with 1 wt.% B4C and 1.5 wt.% Al2O3 MMC indicated the Impact strength value of 30 Joules which is higher than AA 5754 matrix alloy and other compositions.

An attempt has been made to investigate the microstructures and wear behavior of magnesium alloy AM100 (Mg-Al-Mn) based composites reinforced with 7 vol. % of ZrB2, graphite or hybrid of (1:1) ZrB2 and graphite particles as well as the unreinforced magnesium alloy. Magnesium alloy was melt under shield of inert gases and composites were prepared using stir casting method. Optical microscopy was used to study the microstructures of the unreinforced alloy and composites. The composites characterized primarily by the uniform distribution of particles in the matrix and a good adherence between the particles and matrix. XRD analysis was used to identify the phases of the unreinforced alloy and composites. The XRD diffraction pattern of AM100 matrix reveals different phases, namely, Mg, AlMn and Al12Mg17. Formation of these phases is due to the reaction between alloy constituents. Dry sliding wear tests were conducted by using a pin-on-ring apparatus. The wear rates of the composites and matrix alloy were measured at loads of 10, 20 and 30 N, and sliding speed of 0.7 m/s. The worn surfaces of the composite pins were examined by scanning electron microscopy (SEM). The experimental results of the wear tests showed that the magnesium based composites exhibited higher wear rate at all the applied loads when compared to those of the unreinforced magnesium alloy. The ZrB2 reinforced magnesium composite exhibited the lowest wear rate amongst the composites material investigated in the present work.

Automobiles are becoming more and more sophisticated with every passing year. Manufacturers have been trying their best to bring down the kerb weight of their automobiles by using various materials with high strength to weight ratio. The different parts of the automobile are being made much stronger than before in order to comply with the high standards set by NCAP. Hence, this pushes automobile makers to come up with new and innovative methods to manufacture the parts of their automobiles. Our paper addresses the various casting processes used to make automobile parts and also touches on the various materials used to make the components. The casting methods discussed are- Green sand casting, Centrifugal casting, Lost- foam casting, Die casting and Squeeze casting. In the paper we discuss about the most suited materials used for each component and briefly discuss about the pros and cons of each process

The current paper emphasizes various aspects of squeeze casting in the field of metal matrix composites (MMC’s). The effect of different aspects and processing parameters related to squeeze casting such as pressure, slurry temperature, types and effects of reinforcements have been discussed with specific stress on aluminum MMC’s. The development of different mechanical, tribological and wear properties due to squeezing casting have been discussed.

A7075 Hybrid MMCs containing micro B4C and SiC successfully fabricated with different compositions using stir and squeeze casting method. Optical microstructure and SEM images shows the uniform distribution in the A7075 matrix reinforced with 1 % wt. % B4C and 1 % wt. % SiC. The Mechanical properties of A7075/B4C/SiC Hybrid Composites were studied. Hardness of A7075 alloy increased by the addition of 1 wt. % micro SiC and 1.5 wt. % B4C particles to the A7075 matrix. Increase in the hybrid composite is 15.24 % more than the base alloy. Impact strength of composite was decreased as compare to base alloy. In sliding wear studies, the Composite with 1 wt. % B4C has shown less weight loss and coefficient of friction.

This research work deals with the investigation on the study of wear behaviour of squeeze cast aluminium hybrid metal matrix composites. The reinforcement elements are zirconium oxide (ZrO2) and graphite (C).The aluminium hybrid metal matrix composites (MMCs) were produced by squeeze casting method for 6% of ZrO2 and 3% of C by varying the squeeze pressure, molte metal temperature and die preheating temperature. Dry sliding wear test was performed by using pin-on-disc to study the tribological behavior of aluminium hybrid MMCs. Response surface methodology was used to predict the wear strength of the squeeze cast aluminium hybrid metal matrix composites. Results shows that for 150 MPa squeeze pressure, 825 °C and at 250 °C the aluminiumhybrid MMCs recorded minimum wear rate. Squeeze pressure emerges as a influential parameter among the others.

In the current scenario aluminium and their alloys are replaced by composite materials in the automotive field due to low corrosiveness, high strength and less weight. Need for improved wear behaviour performance has led to the design and selection of newer variants of the composite. This present paper investigates the study of wear behaviour of AA6061/Al2O3/SiC metal matrix composite (MMC) using squeeze casting method. Wear test has been carried out on a Pin on Disc apparatus. The effect of three levels and three process parameters such as load, sliding velocity and sliding distance were considered. Statistical analysis plays a significant role in analyzing aluminium matrix composites. Specifically, Taguchi techniques found to be efficient, systematic and simple relative to the optimization of wear test parameters. So that experimental study employed the Taguchi method. L9 orthogonal array was selected to carry out the experiment. Dry sliding wear rate has analyzed on “smaller the best” basis. ANOVA and regression equation carried out to understand the impact of individual factors and interactions on the wear rate as well as the coefficient of friction. Results show that load has the highest influence followed by sliding speed and sliding distance. Scanning Electron Microscope was done on wear surfaces.

In this study, wear behaviour of Aluminum Alloy (AA6063) reinforced with Zirconium Oxide (ZrO2) and Graphite (C) by squeeze casting method was carried out. Squeeze casting method is appropriate for the entire light weight materials similar to aluminium and magnesium which are mainly used in the aerospace and automotive industries. AA6063 is the mainly used alloy for aluminium extrusion. Aluminium hybrid metal matrix composites (MMCs) were fabricated by squeeze casting technique by altering the weight percentage of ZrO2 in steps of 0% up to 6% and keeping C as constant at 3%. Dry sliding wear test was performed by using pin-on-disc to study the tribological behavior of aluminium hybrid MMCs. It is evident from the results that the wear rate is minimum for 6% of ZrO2 and 3% of C reinforcements invariably for all the speeds and loads. The coefficient of friction decreases with the increase in the weight percentage of ZrO2 reinforcements for all the load conditions.

Squeeze casting is a process that can produce the highest quality castings. In the current study, the effect of the process settings and the in-die conditions on rejection rates is studied through a full-scale experimental study. Factors affecting the as-cast part quality were investigated in the current study from two different viewpoints. The first part of the study was to investigate the influence of the process settings on the part rejection rate, and the second was to understand the conditions in the die and the effects on the part rejection rate to understand better the reasons and sensitivity of the squeeze casting process.

In this paper, ZL205A (AlCu5Mn alloy) castings were prepared by squeeze casting. The effects of solution and ageing treatment on the microstructure and mechanical properties of ZL205A castings were studied by metallography, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and mechanical properties tests. The results showed that most of the θ(Al2Cu) and T(Al12CuMn2) phases in squeeze-cast ZL205A dissolved into the α(Al) matrix after solution treatment for 15 h. The fine precipitates gradually increased with the ageing time. The ultimate tensile strength of the specimen aged for 6 h was the highest of 467 MPa and the elongation was up to 15.1%, showing good comprehensive mechanical properties.