论文部分内容阅读
采用扫描透射电镜(STEM)和动态机械分析仪(DMA)研究了FeCrMoCu合金(Cu添加量为1.0%和2.0%,质量分数)在不同冷速条件下Cu的析出行为及其对阻尼性能和力学性能的影响。结果表明:1.0Cu合金中Cu主要以过饱和的形式固溶在基体,当冷速较慢(炉冷)时会析出少量的富Cu相,该相尺寸较小(<5nm),Cu含量较低(3.7%);Cu增加到2.0%后,随着冷速的下降(从水冷到空冷,最后到炉冷),合金中先析出数量较少、尺寸较小的富Cu相,随后析出数量较多、尺寸稍大的球状第二相(10~15nm),最后析出相粗化成圆棒状(100~400nm)但数量显著减少,后2种析出相的Cu含量明显增加(30%~40%)。含Cu第二相的析出,明显增加合金平均内应力,使合金的阻尼性能显著下降,因此有第二相析出的2.0Cu合金阻尼性能明显低于1.0Cu合金。与此同时,合金的强度随着富Cu相的析出而明显提高,其中尺寸较小的富Cu相析出强化效果较好,且对塑韧性的影响相对较小。含1.0%Cu的FeCrMoCu合金可以同时获得较好的阻尼性能和力学性能。
The precipitation behavior of Cu in FeCrMoCu alloy (1.0% Cu and 2.0% Cu) at different cooling rates and its influence on the damping properties and mechanical properties were investigated by scanning electron microscopy (SEM) and dynamic mechanical analyzer (DMA) The impact of performance. The results show that Cu in 1.0Cu alloy is mainly dissolved in matrix in the form of supersaturation. When the cooling rate is slow (furnace cooling), a small amount of Cu-rich phase is precipitated. The phase size is smaller (<5nm) (3.7%). After the Cu content increased to 2.0%, with the decrease of the cooling rate (from water cooling to air cooling and finally to furnace cooling), a small amount of Cu-rich phase with smaller size was first precipitated in the alloy, (10 ~ 15nm). The precipitated phase coarsen into a round rod shape (100 ~ 400nm) but the number decreased significantly. The Cu content of the latter two precipitates increased obviously (30% ~ 40% ). The precipitation of the second phase containing Cu significantly increases the average internal stress of the alloy and significantly reduces the damping capacity of the alloy. Therefore, the damping capacity of the 2.0Cu alloy precipitated from the second phase is obviously lower than that of the 1.0Cu alloy. At the same time, the strength of the alloy increases obviously with the precipitation of the Cu-rich phase. The smaller the Cu-rich phase is, the stronger the precipitation strengthening effect is, and the less the impact on the ductility is. FeCrMoCu alloy containing 1.0% Cu can achieve better damping and mechanical properties at the same time.