Rare Earth Alloy Foam Application And Mechanism Of Action,

The rare earth aluminum foam as a special porous material have broad prospects.The material strength can be imprved by adding rare earth into the aluminum alloy.The casting alloy's processing property and deformation alloy's processability are significantly improved as to the metamorphism,micro-alloying and refinement of rare earth.In this study,high-strength rare earth aluminum foam is researched,By melting foaming process of aluminum foam and adding misch metal La-Ce.The thermodynamic reaction condition and micro effect mechanism between rare earth and AL-Si alloy are researched;Strengthening mechanism of rare earth in the rare earth aluminum foam are also researched.The strengthening phase of AL₁₂Si₄O₁₀(OH)₂,CeCu₄AL₈ and AL₁₁RE₃ are found in the rare earth aluminum alloy by XRD and scanning electron microscopy with X ray energy dispersive spectrometer after the appropriate addition of misch metal La-Ce(0.45 wt%).The shape and size of strengthening phase are changed and the fine particles are dispersed in the alloy as to the refining effect of rare earth.The above combined effects lead to a porous material comprehensive performance improvement.such as the resistant ability of pore wall is enhanced.The experimental results showed that When the contents of the rare earth are within 0.25wt%～0.55wt%, The main effects of rare earth are metamorphism,micro-alloying and refinement.The particles of eutectic silicon are apparently refined.The average density of rare earth aluminum foam is 0.67 g/cm³.The percentage of porosity is 91.3 and the yield strength aluminum foam reached 13.6 MP when the congtent of the rare earth is 0.45wt%.The addition of rare earth,the volume of foaming agent,foam temperature and a series of technology has been optimized,that optimum conditions are:the addition of RE is 0.45 percent,the foam temperature is 680℃,foaming agent content is 1.5wt%,Stirring time is 3 min,the preservation time is 10 min.