摘要
通过对X70管线钢不同厚度含不同V型缺口取向试样在不同温度下三点弯曲断裂试验 ,研究高韧性管线钢缺口取向、试验温度和分层裂纹对材料韧性的耦合效应。发现X70管线钢具有严重的各向异性现象 ,其在平行钢板表面方向和沿钢板厚度方向力学性能差异较大 ;试样缺口取向不同 ,试样破坏形式不同 ,但均产生垂直于板厚方向的分层裂纹 ;分层裂纹的产生可以提高试样的单位厚度裂纹起始功和单位厚度破坏总功 ;分层裂纹以及由分层裂纹所产生的效应主要是试样中的应力状态和材料固有的片状缺陷或夹杂所致 ,有确定的方向性 。
The effects of thickness, notch orientation and delamination on the initial cracking and total works of X70 pipeline steel samples with V notch were investigated experimentally by use of the 3-point bending test in -60℃, -20℃ and 20℃. The couple effect of delamination cracks, thickness, notch orientation and temperature was discovered. The mechanical behaviors of X70 pipeline steel vary with the change of orientation. The failure model is different as the notch orientation of sample changes. Decreases of effective thickness can increase the initial cracking and total works due to delamination crack as the notch direction of sample is along the thickness. The delamination crack perpendicular to the damage face also can increase the initial cracking and total works as the notch direction of sample is along the plate surface. The reason of delaminating crack is the slice defect and the stress state of sample. The delamination crack has certain direction, and the number of the delamination crack has relation to the temperature. The initial cracking and total works of the thick samples are less than the one of the thin samples at the lower temperature. The initial cracking and total works of the thick samples are equal to the one of the thin samples at the higher temperature and it has no relation to the thickness of samples probably.
出处
《压力容器》
2002年第12期20-24,共5页
Pressure Vessel Technology
基金
中国石油天然气集团公司石油管力学和环境行为重点试验室资助项目 (编号ZYT -0 0 0 2 )
