论文部分内容阅读
研究了20Cr11MoVNbNB马氏体热强钢在550—65℃范围内蠕变孔洞的形成及蠕变裂纹的发展发现蠕变孔洞主要在原奥氏体晶界和原板条马氏体边界上的淬火未溶大颗粒Nb（C，N）及M23C6碳化物处形成，孔洞在原奥氏体晶界形成倾向不占优势：蠕变裂纹沿垂直应力方向横穿原奥氏体晶界及原板条马氏体边界向晶内扩展，最终导致穿晶断裂.
The formation of creep pores and the development of creep cracks in 20Cr11MoVNbNB martensitic hot-rolled steel at 550-65 ℃ were studied. It was found that the creep pores mainly quenched and undissolved on the original austenite grain boundaries and the original slab martensite boundaries The formation of large Nb (C, N) and M23C6 carbides is not dominant for the formation of voids at the original austenite grain boundaries: creep cracks traverse the original austenite grain boundaries and the original lath martensite boundaries along the vertical stress Expansion to the crystal, eventually leading to transgranular fracture.