预热对690 MPa级HSLA钢对接接头力学性能的影响

汤忖江, 安同邦, 彭云, 马成勇, 林纯丞, 石照夏, 秦哲

Effect of Preheating on Microstructure and Mechanical Properties of Butt Joint of 690 MPa Grade HSLA Steel

TANG Cunjiang, AN Tongbang, PENG Yun, MA Chengyong, LIN Chuncheng, SHI Zhaoxia, QIN Zhe

图10 不预热焊缝金属冲击断口中微孔及主裂纹的SEM像

Fig.10 SEM images of micro-voids and main crack of impact fracture of weld metal in non-preheating welding (Fig.10c is backscattered electron (BSE) image, the others are secondary electron (SE) images, I—micro-voids appeared in AF, II—micro-voids appeared in B, III—micro-voids formed around AF and B interface, IV—micro-voids formed around M-A and AF interface, V—micro-voids formed at grain boundary, VI—micro-voids formed around inclusions, the same I~VI below) (a) SEM image of impact sample center (solid circles indicate observation regions), (b, c) observation region 1 in Fig.10a, (d) observation region 2 in Fig.10a (solid rectangle indicate deflection of main crack)