Abstract��To the problem of cracking of the tensile specimen surface of NM400 wear-resistant steel after tensile deformation, the fracture, surface cracks and microstructure were investigated by optical microscopy, electron scanning microscopy and energy spectroscopy. The results show that the surface cracking resulted from the process between rolling and quenching, which may be the cooling process on the cooling bed after rolling or flame cutting process. Some inclusions distributed at grain boundary weakening the boundary, and under the effect of internal stress, the inclusions became cracking source. During the subsequent process of quenching, the crack appears the high temperature oxidation and slight decarburization.
�ƽ�� ��С÷�����Ǿ꣬��������ѩ��. ��ĥ��NM400������濪��ԭ�����[J]. �й������ڿ���, 2014, 32(2): 31-35.
YANG Jian-ping,QIN Xiao-mei,ZHAO Ya-juan,TIAN Li,LI Xue-jie. Analysis on Cracking of the Tensile Specimen Surface of NM400 Sear-Resistant Steel. Chinese Journal of Iron and Steel, 2014, 32(2): 31-35.