钢网架用高强螺栓的断裂原因分析  

Reason Analysis on Fracture of a High-Strength Bolt for Steel Grid Structure

作　　者：王军[1] 李桂芹[1] 苏建锋[1] 尹亚豪 

机构地区：[1]国家金属制品质量监督检验中心,郑州450001

出　　处：《理化检验（物理分册）》2017年第7期500-503,共4页Physical Testing and Chemical Analysis(Part A:Physical Testing)

摘　　要：某钢网架厂房中的高强螺栓在使用过程中出现早期断裂现象。采用宏观检验、化学成分分析、硬度测试、扫描电镜及能谱分析等方法,对螺栓断裂的原因进行了分析。结果表明:该高强螺栓断裂主要是由于其内部存在冶金缺陷及热处理工艺不当;在承载力作用下,存在较多夹渣缺陷的螺栓心部产生应力集中并萌生裂纹,同时不良的调质热处理组织增加了螺栓的脆性,从而导致了螺栓的快速脆性断裂。最后提出了相应的预防措施。A high-strength bolt for steel grid structure fractured early during use. Base on macroscopic inspection, chemical composition analysis, hardness testing, scanning electron microscope and spectrum analysis and so on, the fracture reasons of the bolt were analyzed. The results show that： the fracture or the bolt was mainly caused by the presence of raetallurgical defects and inadequate heat treatment technology; under the action of the load, the stress concentration was produced in the center of the bolt with a large number of slag inclusions, then crack source appeared in the region of the stress concentration; meanwhile, the poor tempering heat treatmenl structure increased the brittleness of the holt, and ultimately resulted in the rapid brittleness fracture of the bolt. Finally the corresponding preventive measures were put forward.

关 键 词：高强螺栓 脆性断裂 冶金缺陷 调质热处理 

分 类 号：TG115.2[金属学及工艺—物理冶金]