Mechanical properties and wear resistance of direct energy deposited Fe–12Mn–5Cr–1Ni-0.4C steel deposited on spheroidal graphite cast iron

Abstract

This study investigates the wear resistance of an Fe–12Mn–5Cr–1Ni-0.4C (high-manganese steel) produced by direct energy deposition (DED) and spheroidal graphite cast iron. The high-manganese steel was deposited on the spheroidal graphite cast iron substrate. Near the deposit/substrate interface, the graphite phases of the cast iron are completely solutionized owing to the low carbon content of the high-manganese steel. In addition, the steel was deposited with a dense microstructure without interfacial cracks owing to the strong austenite stabilization effect. The wear behavior for various wear loads and sliding speeds was studied using ball-on-disk tribology tests with counterpart balls (KS STB2 bearing steel). The results show that the wear rates of the deposited high-manganese steel and the spheroidal graphite cast iron depended more on the wear load than on the sliding speed. At a low wear load of 20 N or less, the spheroidal graphite cast iron showed a higher wear rate than the deposited high-manganese steel owing to the self-lubricating effect of graphite. When the wear load condition was 50 N, the high-manganese steel had a higher wear resistance than the cast iron owing to the work-hardening effect. Therefore, it is expected that high-manganese steels, produced by DED, with high wear resistance under a high wear load will be effective for repairing spheroidal graphite cast iron products.