【摘要】 采用光学显微镜、扫描电镜及能谱分析(EDX)等手段研究了Q690D钢板拉伸试样的分层现象及其显微组织方面的原因。试验结果表明,分层试样中裂纹附近的贝氏体组织中存在条带状分布的珠光体,同时在分层面上出现密集的(Nb,Ti)C颗粒,这些异常组织是导致Q690D钢板拉伸试样出现分层的主要原因。通过调整钢板的轧制工艺参数和消除组织缺陷,能有效防止Q690D钢板试样拉伸时的分层开裂。更多还原

【Abstract】 The delamination behavior in tensile specimens of Q690D steel plate and its reasons with relation to microstructure were investigated by means of OM,SEM and EDX.The results show that banded pearlite exists in bainite near crack in the delaminating specimen,and that close(Nb,Ti)C particles were found at the delamination face.The delamination of the Q690D steel plate specimen during tensile test arises mainly from these undesirable microstructures.The adjustment of rolling process parameters and the elimination of the poor microstructures can effectively prevent the Q690D steel plate specimen from delaminating and cracking during tensile test.更多还原