Preparation And Properties Of Foam Magnesium Alloy

As a new type of functional material, foamed metal is attached importance to the high technology areas improving rapidly due to its special structure and performance characteristics. The research of foamed metal in preparation, property and applications is more widely and deeply. But there are many problems of foamed metal from preparation to application which are not solved. In this condition, we make deeply research of foamed metal in the preparations and properties.Based on previous research experiences, further theoretical analysis and many tests, we successfully prepared foamed metal samples in the ways of vacuum infiltration casting with NaCl particulate and plaster mold. We also research the properties of foamed metal in compression performance and heat dispersion. Through the researches and analysis, we get results as follows:(1) In vacuum infiltration process, NaCl particles was selected as filling material and was compacted in mold layer by layer. Four pouring parameters , preheating temperature of particle, Melting temperature, pouring temperature and vacuum degree were determined as 590～610℃,760～780℃, 720～730℃and -0.03Mpa, respectively. Particle cleaning process was improved to resisting NaCl corrosion, which included water washing and brushing, soaking self-made solution, high pressure water washing and high pressure air drying. The samples were obtained with 40%-75% porosity. The largest sample is cylindrical with 75mm diameter, 100mm high.(2) Sponginess magnesium alloy was prepared by using porous plaster mold. In this process, the adding quantity of MgSO4 was 15 wt% of plaster, the ratio of water and solid material 0.55. The plaster mold was heated and baked step by step. The pouring parameters are similar with vacuum infiltration process. Plaster was cleaned by water washing and vibration. The inertia gas was adopted to prevent explosion and combustion in pouring. The sample structure inherited the sponge structure, which pore diameter was 5mm and porosity 95%. (3) The compression deformation characteristic of foamed Mg and the effects of porosity, material and pore size on compression property were investigated, which can provide necessary theory for the application of energy absorption. The material has the most influence on compression property. To the same material, with increasing relative density, the yield stress increased and yield region decreased. Pore size had low effect to yield strength.(4)Determined the thermal conductivity of foamed magnesium alloy. By the analysis of its thermophysical properties and structures, we manufacture the radiator on computer CPU and test the effect.