摘要
利用透射电子显微镜(TEM)技术研究了12Cr2MoWVTiB耐热钢焊缝区产生裂纹的微观机理。文中提出,粒状贝氏体中大量的富氢微孪晶马氏体M-A小岛引起的延迟微裂纹;柱状晶晶界间的多晶低熔共晶膜引起的结晶裂纹以及外加拘束应力等三者之间的相互作用,导致该裂纹的产生。初步讨论了避免焊缝裂纹的方法。首次在TEM下观察到了低熔共晶膜的形态。
The microcracking Mechanism of weld of 12Cr2MoWVTib heat-resisting steel has been studied under TEM. The results show that the crack is caused by the interaction of three factors: 1. lots of hydrogen-rich austenite and micro-twin martensite (M-A) islands in granular bainite induce the delayed crack; 2. The polycrystalline eutectic film existing in the boundary of primary austenite causes the solidification crack; 3. External restraint stress. The method for reducing the cracks is discussed and the TEM morphology of the eutectic film is first observed.
出处
《材料科学与工艺》
EI
CAS
CSCD
北大核心
1993年第4期87-90,共4页
Materials Science and Technology
