한국주조공학회

Effects of Cr and Ni addition on damping capacity, mechanical property, and corrosion resistance of Fe-l7%Mn martensitic alloy have been studied. Martensite start temperature(MS) of the alloy decreases linearly with increasing Cr and Ni contents up to 15%. The damping capacity decreases gradually from 27 to 22% in specific damping capacity(SDC) with increasing Cr and Ni contents from zero to 10%, and decreases rapidly with further Cr and Ni content in Fe-l7%Mn alloy. The tensile strength of the alloy main- tains a level of 60 kgf/mmz regardless of Cr content with an elongation of 20 to 25%. But, in case of Fe-17%Mn-X%Ni alloy, the tensile strength decreased rapidly with the Ni content of above 10% because of austenite morphology. Immersion test in 5% NaCl solution leads to the result that the corrosion resistance of the alloy becomes excellent above 10% Cr. From the above results, it is concluded that the optimum Cr content to improve the mechanical property and corrosion resistance of the alloy in 5%NaCl solu- tion with a lesser decrease in damping capacity is about 10%. In the case of 5% HZSO4 condition, the Fe- l7%Mn-10%Ni is an opti- mum alloy.

specific damping capacity(SDC), mechanical property, 3-martensite, corrosion rate, martensite start temperature