Effect of nitrogen on damping, mechanical and corrosive properties of Fe–Mn alloys

The influence of alloying by nitrogen on the damping capacity of Fe–14Mn and Fe–16.5Mn wt.% alloys was studied by means of the amplitude-dependent internal friction technique. Also, the effect of nitrogen on phase constitution, mechanical properties and resistance to immersion corrosion was investigated. It was found that the Fe–14Mn alloy possesses a much higher level of damping capacity than the Fe–16.5Mn alloy. The addition of approximately 0.1 wt.% of nitrogen slightly affects the damping capacity of the Fe–14Mn alloy and increases it in the Fe–16.5Mn alloy. At the same time the ultimate tensile strength of the Fe–16.5Mn alloy is increased from 455 to 655 MPa, and the uniform elongation increased from 3.3 to 12.4%. The ultimate tensile strength of the Fe–14Mn alloy is increased from 480 to 660 MPa due to nitrogen alloying, while the uniform elongation is slightly lowered from 5.1 to 4.1%. The corrosion resistance in 1 N sulphuric acid solution is improved by more than two times in both alloys due to nitrogen alloying.