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As aerospace, electronics and other industries instrumentation equipment and spare parts of automobile transportation, \But aluminum (magnesium) alloy castings LFC prone porosity, shrinkage defects, reducing the casting density, deterioration of the mechanical properties of the casting, which restricts the aluminum (magnesium) alloy LFC further development. As a result of pressure solidification, can reduce the porosity and shrinkage, improve casting density and mechanical properties. Therefore, the pressure solidification and aluminum (magnesium) alloy combine EPC can effectively improve the lost foam casting performance. This successful development of EPC pressure coagulation test device. Using the device for a single-factor stress coagulation tests, testing the effects of different pressure on the aluminum (magnesium) alloy lost foam casting porosity, density, hardness, tensile strength, elongation and Microstructure. Select the optimal pressure parameters, testing the effects of different pressurization rate on the microstructure and mechanical properties of castings effects found on better compression rate. Further research under pressure solidification process, the casting thickness on tissue properties. Finally select the optimal pressure solidification process parameters, pilot production structures between the three parts, explores the aluminum (magnesium) alloy solidification LFC pressure applied in the industrial production feasibility. The results show that: with the increase in air pressure is applied, the casting microstructure refinement, density and mechanical properties gradually increase the porosity decreased significantly when the applied pressure reaches 0.5MPa, ZL101 Aluminum Alloy Lost Foam Casting pinhole disappeared; pressure continues to increase, improve mechanical properties of casting slowdown; pressure is constant, the pressure rate of 0.003MPa / s ~ 0.03MPa / s when, ZL101 Aluminum Alloy Lost Foam Casting better performance; pressure reduces the casting solidification on organizational performance thickness sensitivity; LFC pressure will be applied to aluminum lost foam casting solidification production, can improve casting forming ability, density and mechanical properties. The pressure applied to AZ91D magnesium alloy solidification lost foam casting production due to the latent heat of crystallization of magnesium alloy, the solidification interval large compared with ZL101 aluminum, mobility decreased, filling poor; easily oxidized during melting and pouring, casting local prone to osteoporosis, lack of water and other defects. In this paper, aluminum (magnesium) alloy solidification LFC pressure for a more systematic experimental study, its practical application laid the initial foundation, but the pressure solidification mathematical model of the mechanism needs further improvement, the pressure solidification degree of mechanization and test equipment Real-time detection test parameters could be improved, the pressure lost foam casting magnesium alloy solidification process parameters need to be further refined research.
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