【摘要】 利用JN-1型倒扭摆仪对比研究了Fe-Mn合金经等通道转角挤压(ECAP)及不同温度退火后的阻尼性能变化,利用光学显微镜和透射电镜观察分析了合金的微观组织。结果表明,合金经ECAP及较低温度(600℃)退火后,组织中存在大量高密度位错和明显的带状组织,阻碍阻尼源的运动,导致阻尼性能消失;随退火温度升高(700～800℃),高密度位错和带状组织逐步消失,ε马氏体数量较未ECAP的多且片层更细小,单位体积内界面面积增加,振动的阻尼源增多,故阻尼性能显著提高;当退火温度进一步升高时(900～1000℃),由于ε马氏体片有所长大,合金的阻尼性能出现下降趋势,但仍高于未ECAP状态。更多还原

【Abstract】 The damping capacity of Fe-Mn alloy which was subjected to equal channel angular pressing (ECAP) and subsequent annealed at different temperatures was measured by reversal torsion device. The microstructure was observed using the optical microscope and transmission electronic microscope. The results show that after ECAP and annealing at low temperature (600 ℃), there are lots of high-density dislocations and obvious banded structures, which inhibit the slip of damping resources and result in the low damping capacity. With increasing annealing temperature (700～800 ℃), high-density dislocations and banded structures gradually disappear. The amount of ε martensite is larger than that of specimen without ECAP, and the martensite flakes are much refiner. The increasing interfaces per unit volume result in more damping resources on vibration, thus improve damping capacity remarkably. With further increasing annealing temperature (900～1 000 ℃), the martensite flakes grow up slightly, so the damping capacity of Fe-Mn alloy decreases, but it is still higher than that of specimen without ECAP.更多还原