Microstructures And Properties Of Aluminum Alloy With Heat- And Wear-Resistance Prepared By Spray Forming

A kind of aluminum alloy with high silicon and high iron is designed to meet the requirement of light wight, high heat-resistance, high wear-resistance, low thermal expansion and high thermal conduction. Its chemical composition is Al—17Si—4Fe—3Ni—2Mn—3.5Cu—IMg. The microstructure is composed of many granular phases, small blocked phase and matrix by Spray -Deposited technology in contrast with that of coarse needle-shaped phase, large-blocked primary silicon and eutectic mixtures by casting metallurgy. Under various exposure temperature, it shows that the microstructure is stable and the hardness is reduced by 6% at exposure temperature of 150°C for 100 hours. High thermal resistance benefits from the fact that iron-rich phases stop matrix from coarsening and primary silicon from growing rapidly. Narrow and small furrow are formed in the wear profile. Thus the mechanism is grit wear. Fine secondary phases have an effect of solid lubrication.