纳米晶Fe-25%Ni合金块材的内耗研究

INTERNAL FRICTION OF NANO-GRAINED Fe-25%Ni ALLOY BULK

运用动态力学分析仪(DMA)测量了惰性气体冷凝原位温压固结制备的纳米晶Fe-25％Ni(原子分数)块材的滞弹性谱,测试温度在20--400℃之间。观察到200℃附近有一内耗峰,并伴随有模量的软化。X射线衍射结果表明,此峰与应力诱发马氏体逆相变有关。讨论了模量随温度的升高而升高的异常变化。

The anelasticity spectrum of a nano-grained Fe-25%Ni (atomic fraction) bulk prepared by an inert gas condensation and in situ warm consolidation technique was measured in the 20-400 degreesC temperature range by means of a dynamic mechanical analyzer (DMA). An internal friction peak accompanied with soft modulus was observed near 200 degreesC. It was proved by XRD results that the peak was associated with the reverse phase transformation of stress-induced martensite. The abnormal modulus-temperature spectrum was observed and discussed.