热循环对Fe-19Mn阻尼合金组织和性能的影响

采用Olympus光学显微镜XRD以及倒扭摆法,研究了热循环温度对Fe-19Mn合金的微观组织和阻尼性能的影响。结果表明,当热循环温度在As以下时,ε马氏体形貌基本保持不变,由于淬火空位的浓度降低,阻尼性能提高;当热循环温度在As与Af之间,合金内马氏体明显粗大,减少了合金阻尼源界面,阻尼性能降低;当热循环温度高于Af时,由于反复的ε圮γ相变过程,导致马氏体形貌的明显改变,进而影响到合金的阻尼性能,随循环温度的提高,合金的马氏体形貌和阻尼性能都逐渐恢复到固溶态水平。

Effect of Thermal Cycling on Microstructure and Properties of Fe-19Mn Damping Alloy

The effects of thermal cycling temperature on microstructure and damping capacity of Fe-19Mn alloy were studied by Olympus optical microscope, XRD and reversal torsion pendulum. The results show that, when upper peak temperature is below A_s, the damping capacity is improved due to quenched-vacancy decaying. When upper peak temperature is between A_s and A_f, because e martensite plates become wider, the interface phase between ε martensite decreases, which reduces damping capacity dramatically. When upper peak temperature is above A_f, the morphology of the alloy greatly changes owing to the repetition of ε←→γ , which alters the damping capacity of the alloy. With the increase of temperature, the morphology of martensite and damping capacity of the alloy return to as-quenched gradually.