15MnVN钢疲劳短裂纹生长演化特性  

Short Crack Growth Behavior of 15MnVN Steel

作　　者：陈家权[1] 沈炜良 李文娟[1] 马兆敏[1] 

机构地区：[1]广西大学机械工程学院,530004

出　　处：《现代机械》2003年第1期63-65,共3页Modern Machinery

摘　　要：对循环载荷作用下 15MnVN钢的显微组织变形、微观裂纹的萌生和短裂纹扩展过程进行了研究。结果表明 ,在孔边应力集中处 ,显微组织的变形是不均匀的 ,其主要集中在铁素体晶粒内。在循环载荷作用下 ,晶内滑移带与晶界相互作用 ,形成晶界微裂纹。微裂纹合并形成短裂纹。裂纹尖端塑性区内晶粒同样经历裂纹的萌生和扩展过程。在短裂纹范围内 ,裂纹的扩展过程有很大的随机性。分析结果表明 ,短裂纹的扩展过程符合对数正态分布。In this study,the behaviors of deformation,microcrack initiation and short crack growth were investigated for 15MnVN steel.The observations showed that the deformation near small holes was mainly caused in parts of ferritecrystalline grains,and the reaction between dislocation slip bands and crystalline boundaries formed micro-cracks,which would merge together to form short cracks.Short crack growth possesses significant scatter for the stochastic distribution of material microstructure.According to the analysis of experimental data,short crack growth process is subordinated to logarithmic normal distribution.

关 键 词：15MNVN钢 疲劳 短裂纹 裂纹扩展 随机过程 

分 类 号：TG142.41[一般工业技术—材料科学与工程] TG111.8[金属学及工艺—金属材料]