高碳钢盘条在拉拔前发生脆断的原因分析

通过SEM电子显微镜观察了不同牌号的高碳钢盘条在使用前或机械剥壳过程中发生脆断的断口形貌,利用光学显微镜检验了脆断盘条断口处对应的金相组织,分析了盘条发生脆断的原因。结果表明,盘条在吊装或运输过程中,由于碰撞或摩擦等机械外力作用造成盘条表面局部金属发生剧烈变形,导致盘条表面组织发生变化,形成应力集中从而诱发裂纹,最终造成盘条在使用前或机械剥壳过程中发生脆断。

ANALYSIS OF BRITTLE FRACTURE ON HIGH CARBON STEEL WIRE ROD OCCURRED BEFORE DRAWING

Brittle fractures on different grades of high carbon steel wire presented before used or during mechanical shelling were observed by SEM electronic microscope,microstructures of the fractures were tested by optical microscope inspection and the reasons were analized. The results show that,because of external forces,intense deformation occurs for the partial metals on the surface of the wires during lifting and transporting,thus the surface structures are changed and stress concentration is formed so as to cause cracks. Finally,brittle fractures present before used or during mechanical shelling.