0Cr14Mn21NiN奥氏体不锈钢的析出行为

采用Thermal-Calc热力学计算软件对0Cr14Mn21NiN奥氏体不锈钢C、Cr含量变化对试验钢碳化物析出热力学特征进行了计算。通过光学显微镜、扫描电镜、透射电镜等分析方法探讨了时效温度、保温时间、变形对试验钢析出行为的影响。结果表明:析出相主要是在晶界处产生的Cr₂₃C₆,试验钢析出敏感温度为750~850 ℃。在800 ℃下时效30 min的试验钢晶界处可以明显观察到析出相的产生,随保温时间的延长,析出相含量逐渐增多,尺寸变大,并逐渐向晶内生长。时效前的变形明显缩短了析出相的孕育时间,变形后保温1 min的试验钢晶界处可观察到较多析出相的产生,晶界明显变粗。

Precipitation behavior of 0Cr14Mn21NiN austenitic stainless steel

Thermo-mechanical calculation software of Thermal-Calc was used to calculate the thermodynamic characteristics of carbide precipitation in 0Cr14Mn21 NiN austenitic stainless steel. The effects of aging temperature,holding time and deformation on the precipitation behavior of the experimental steel were investigated by means of metallographic microscope,scanning electron microscopy and transmission electron microscopy. The results show that the precipitation phase is mainly Cr23C6 produced at the grain boundary,and the sensitive temperature for precipitation of the experimental steel is about 750-850 ℃.The precipitation phase can be obviously observed at the grain boundary of the experimental steel aged at 800 ℃ for 30 min. With the prolongation of the holding time,the content of the precipitated phase increases gradually,the size becomes larger,and gradually grows into the grain. The deformation before aging significantly shortens the incubation time of the precipitated phase,and more precipitated phases can be observed at the grain boundary of the experimental steel when kept for 1 min after deformation,and the grain boundary becomes coarsened.