Study On The Microstructures And Properties Of Medium Carbon High Boron Ironed Cast Wear-resistant Alloy

In this dissertation,the solidification process,solidification microstructures and Properties of high boron iron-based alloy which carbon content is about 0.4%and boron content is 0.5 to 3.0%have been researched.At same time,the microstructures,phase composition and properties after queached at 950℃,1000℃,1050℃and tempered at 200℃have been researched.Under differtent wear conditions(two-body abrasion and three-body abrasion),the wear resistance of alloy is investigated by means of wear test on ML-10 model pin-disk and MLD-10 impact abrasion test,and wear mechanisms are analyzed under different working conditions.The results showed that:with increasing of boron content, boron carbide compound volume fraction of medium carbon-high boron iron-based alloy shows a rule of exponential curvey:y= 7.078e^0.822x.Austenitizing temperature has a relatively high impact on alloy which boron content is less than 1.5%,the microstructure appears obvious acicular martensite at an austenitizing temperature of 1050℃.But,austenitizing temperature has a weak effect on alloy which boron content is more than 1.5%,matrix structure still remains lath martensite.Under two body abrasion,When boron content is less than.1.5%,the wear resistance of high boron iron-based alloy is equal to that of high chromium cast iron.When boron content is more than 1.5%,the wear resistance of high boron iron-based alloy is significantly higher than that of high chromium casting iron.The higher the boron content,the higher wear resistance of high boron iron-based alloy.Under three body abrasion,When boron content is less than 1.5%,the wear resistance of high boron iron-based alloy is better than that of high chromium cast iron.When boron content is more than 2.0%,the wear resistance of high boron iron-based alloy is worse than that of high chromium cast iron.