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Microstructure and tensile properties of squeeze cast Mg-Al-Ca alloys with different levels of calcium addition (AMC50X) were studied. The microstructural analysis by optical and scanning electron microscopy (SEM) shows that the squzeeze cast Mg-Al-Ca alloys contain primary α-Mg, (Al, Mg)₂Ca and Mn-Al intermetallic while the base alloy AM50 contains primary α-Mg, β-Mg₁₂Al₁₇ and Mn-Al intermetallic. The addition of calcium varying from 1 to 4 wt.% increases the fraction area of Ca-containing secondary phases from 9.5% to 19.5%. The experimental observation confirms also that the calcium has a grain refining effect on the base alloy AM50A. The tensile testing results indicate that, as the calcium content of AMC50X alloys increases from 0 to 4%, the ultimate tensile strength (UTS) and elongation (E_f) decrease dramatically at room temperature as their yield strengths (YS) improves slightly. At 150°C, however, both the UTS and YS of the alloys increase with increasing the Ca content.

Zinc-coated steel wires (1–5 numbers) reinforced in LM6 matrix composites have been prepared by squeeze casting process. Microstructure, hardness, tensile strength, ductility and dry sliding wear behavior of composites have been investigated by varying sliding distance and load. Fracture surface of tensile specimens and worn out surface of wear samples have been examined using field emission scanning electron microscope (FESEM). The results reveal that hardness of composites increased with increasing distance from matrix to steel wires. Maximum hardness values of 751 VHN and 611 VHN are observed in steel wire and at the interface of steel wire — aluminium, respectively. Tensile strength of composites increased upto 24% by reinforcing three steel wires in matrix. During the wear test, weight loss, wear rate and coefficient of friction decreased with increasing number of wires embedded in matrix and increased with increasing sliding distance and load. LM6 aluminium alloy reinforced with five numbers of steel wires decreased the weight loss upto 17% as compared to matrix under 40N load and a sliding distance of 2000m. Fracture surface of tensile specimen shows dimple formation in matrix and broken wires are observed in composites. Worn surface of composites shows fine grooves, whereas delamination is observed in matrix. In general, reinforcement of zinc-coated steel wires in LM6 aluminium alloy exhibited better mechanical properties and wear resistance compared to matrix.

In this research, aluminum matrix composites reinforced with continuous carbon fibers (CFs) were fabricated using A356 aluminum alloy and PAN-based CFs by squeeze casting. For this purpose, CFs were first coated with a nickel layer using the electroless method and then the microstructure of the nickel–phosphorus (Ni–P) electroless coating was investigated. In the next step, composite samples reinforced with volume fractions of 5, 10, and 15 vol.% CFs coated with Ni–P coating were fabricated by squeeze casting at 60 MPa, and then microstructure and mechanical properties were examined. The results of the bending test on the composite samples indicated that the nickel coating had a significant effect on the flexural strength of the composite and increased the flexural strength by up to 30%. In addition, with the increase in the volume percentage of the fibers, the hardness of the samples increased while both the wear rate and the coefficient of friction decreased. Moreover, the best wear resistance was observed in the sample containing 15 vol.% as-coated carbon fibers. The Ni coating led to the formation of a mechanically mixed layer (MML) containing a fine mixture of metallic oxides and carbon thus enhancing the wear resistance.

The piston in the automobile engine must withstand high stress and temperatures and also have low weight. The alloy of Al-Si is the most commonly used in the piston. The reinforcement using ceramics, fibres or nanoparticles will increase the properties of the piston alloy. In this work, the piston alloy is fabricated as a metal matrix composite of Al-Si reinforced by TiC-MoS₂ using the squeeze casting method. The squeeze casting effect on the matrix and the reinforcement is studied using tensile testing and microstructure analysis. The strength hardness obtained from the experimentation gives the highest tensile strength of 330 MPa and the hardness of 110HBN. The fractography and morphology are investigated using SEM (scanning electron microscope), resulting in the lowest porosity of 3.21% obtained in the composite material. The tribological behavior was also investigated at the condition of dry Sliding using pin on disc tribometer gives the lowest coefficient friction of 0.31 and the wear rate of 0.0051 mm³/m. The experiment is numerically designed and optimized using the response surface methodology (RSM). The obtained value is predicted and validated using a hybrid approach of deep belief network-reptile swarm algorithm (DBN-RSA). The regression of the parameters is about 99.97% showing that the model is very accurate to the experimental results. The RMSE of the proposed method implies less error and shows the accuracy level of the parameters. The result shows that the designed model is best fitted for the tribological and mechanical properties investigation of metal matrix composite.

In this paper, we fabricate ADC12 aluminum alloy connecting rods by using squeeze casting, and compare microstructure and mechanical properties of connecting rod parts made by different processes, thereby the effect and mechanism of supercharging pressure, supercharging speed, liquid aluminum temperature to feeding capacity of pouring system is analyzed. The results indicated that, under the condition of supercharging speed 1.5-2.0m/s, supercharging pressure 90-100Mpa and liquid aluminum temperature 670-680°C, high level quality connecting rod with dense microstructure and high mechanical properties is achieved; proper supercharging pressure, supercharging speed and liquid aluminum temperature can improve the production quality stability.

Using image analysis, density and porosity measurement, the microstructure of Mg-Al-Ca alloy prepared by squeeze casting under different pressures was investigated. The results show that increasing applied pressure decreases the thickness of the plate-like phase in the alloy, the fraction of second phase and the porosity level of the alloy, while increases the density.