High Temperature Reaction of MgO in Al203-SiC-C-Si-Al Composite

摘要

Research of the influence on property of adding small quantity of MgO fine powder into Aluminum & Silicon combined Al2O3-SiC-C composite, and discussed possible high temperature reactions of MgO in Al2O3-SiC-C-Si-Al composite.Results show: (1)After adding small quantity of MgO fine powder into aluminum & silicon combined Al2O3-SiC-C composite,reduction reaction of MgO and C, Si, Al, SiC etc comes out as Mg vapor, CO and other gas.These gases will weaken the material and have some influence on resistance to oxidation.(2)MgO, Al2O3 and SiO2 (oxidized from Si), etc form a complex composite, large quantity of low melting phase will form in this composite at high temperature, and it will recede the expansion caused by spinel forming,resulting in obvious shrinkage of material.