选区激光熔融制备FeCoCrNiMn-(N,Si)高熵合金在冷轧变形及500℃长时间退火后的析出行为

Precipitation in a selective laser melted FeCoCrNiMn‒(N,Si)high entropy alloy after cold rolling and prolonged annealing at 500℃

对选区激光熔融制备的FeCoCrNiMn-(N,Si)高熵合金先进行冷轧变形,然后在500℃进行长时间退火处理,研究长时间退火对其相稳定性及微观组织演变的影响。研究结果表明,在退火温度为500℃,退火时间为10~40 d时,合金基体内形成了3种类型的沉淀析出物(Cr_(2)N相、BCC-Cr相和L1_(0)-NiMn相),且氮原子的添加抑制了富FeCo相的形成;当退火时间从10 d增加到20 d时,沉淀物的尺寸显著增加。然而,当退火时间进一步增加到40 d时,沉淀物颗粒不长大,其尺寸保持不变。

The high entropy FeCoCrNiMn-(N,Si)alloy prepared by selective laser melting was first cold-rolled and then annealed at 500℃for a long time.The effect of long annealing on the phase stability and microstructure evolution was studied.The results indicate that three types of precipitates(Cr_(2)N phase,BCC-Cr phase and L1_(0)-NiMn phase)form inside the alloy matrix after annealing at 500℃for 10−40 d.The existence of nitrogen atoms inhibits the formation of FeCo-rich phase.In addition,the size of precipitates increases obviously with the annealing time from 10 d to 20 d.While the annealing period further increases to 40 d,the size of precipitates particle remains the same.