Abstract: The precipitated phases in microalloy steel 40MnV-0.36~0.40C,1.36~1.40Mn,0.55～0.65Si,0.8 ~0.9V,0.011～0.016Ti,0.021～0.045Al,0.007～0.016N have been calculated by Thermocale and Dicta software, and the chemical compositions, morphology and distribution of the precipitated phases were studied by electrolytic analysis X- ray diffraction analysis and transmission electron microscope examination. The results showed that minor N and Ti in steel led to coarse particle of TiN with size 50 nm precipitated at liquid- solid two phase region. With temperature decreasing, the size of precipitated phases gradually decreased to less than 10 nm of which the shape was modified to round from square, and the V and C content in precipitated phases increased besides the N and Ti content decreased. With aluminum content in steel increasing, the amount of VN precipitation decreased.

摘要： 用Thermocale和Dicta软件对微合金钢40MnV(%:0.36～0.40C,1.36～1.40Mn,0.8～0.9V,0.011～0.016Ti,0.021～0.045Al,0.007～0.016N)中的析出相进行计算,并用电解分析,X衍射,透射电镜研究了析出相的成分、形貌和分布。结果表明,钢中少量的N和Ti可导致在固液两相区析出尺寸为50nm的粗大TiN颗粒。随温度降低,析出相尺寸逐渐减小到10nm以下,形状由方形变成圆形,且析出相中V和C含量增加,N和Ti含量减少。随着钢中铝含量的增加,VN析出量减少。

关键词: 40MnV微合金钢, Ti , N , M(C,N), , 固液两相区