Influence of Gas Nitriding on the Damping Capacity of Fe-17Mn Alloy

Fe-17Mn alloy has been attracted as a high damping alloy due to its excellent damping capacity and tensile properties. For its industrial application, it is necessary to improve both wear resistance and anti-oxidation. To solve this problem, gas nitriding was performed at 520 °C for 10 h using cold-rolled specimens. The nitrided specimen revealed a thick nitride layer of ~ 68 μm with ~ 20%Mn and a hardness value of ~ 650 Hv on the matrix of ε martensite and γ austenite without the diffusion layer. The damping capacity of the nitrided specimen was decreased with increasing the thickness ratio of nitride layer to matrix. However, when the thickness ratio was ≤ 1.5%, the damping capacity of the nitrided specimen was similar to that of the nitride-free specimen. This indicates that the wear resistance and anti-oxidation of Fe-17Mn alloy can be improved by a thin nitride layer without the loss of its damping capacity.