摘要
对不同厚度油气输送管线钢进行各种裂纹的断裂试验,对各裂纹的断口进行了分析,探讨了分层机理及其对不同形式裂纹体承载能力的影响。结果表明,分层在各裂纹形式中均存在,此钢在室温为韧性断裂。对于非穿透裂纹,裂纹先起裂,穿透后情形就与穿透裂纹相似,由于扩展初期无分层,裂纹端部保持高的三维应力约束,所以其起裂应力强度比穿透裂纹要低。因此不能直接用穿透裂纹试验得到的断裂韧度值来评定管道中的非穿透裂纹起裂。
The mechanism of delamination of a kind of pipeline steel and its effect on fracture were analyzed from fracture experiments and a fractographic investigation was made at fracture surface. It was found that delamination and ductile fracture are the material characteristics; For part-through crack specimens, the main crack initiates before delamination forms. The three-dimensional stress constraint of crack tip is much high without delamination, so the initiation toughness of part-through crack is lower than that of through thickness crack specimens. It may be extraordinary dangerous to assess part-through crack initiation directly by using through-thickness crack data.
出处
《机械工程材料》
CAS
CSCD
北大核心
2003年第7期9-11,21,共4页
Materials For Mechanical Engineering
基金
国家杰出青年科学基金(59625510)
