摘要
钛合金螺钉在装配过程中发生断裂失效,对装配和模拟扭转试验过程中断裂的钛合金螺钉断口进行了宏微观观察和能谱成分分析,对同批次螺钉进行了应力持久试验,对失效钛合金螺钉的金相组织进行了检查。结果表明,螺钉的断裂性质相同,均为脆性断裂;螺钉断裂的主要原因是存在内部缺陷,而与氢致脆性断裂的关系不大;螺钉的内部缺陷可能是在锻造过程后期由于某种偶然因素造成了原始β晶界开裂所致。
Several titanium alloy screws of two different sizes fractured during assembling. Fracture characteristics observations and of chemical composition analysis were performed for the fractured screws happened during assembling and simulated torsion experiments. Stress endurance tests were performed for titanium alloy screws which were the same batch with failed ones. Micro- structure of the failed screws was observed. The results showed that screw fracturing was brittle fracture. The main cause of screw fracturing was the existence of inner defects, and there was no obvious relation to hydrogen-induced brittle. The inner defects of screws were probably resulted from original grain boundary of β phase cracking caused by certain occasional factor during the later stage of forging.
出处
《失效分析与预防》
2007年第2期29-33,共5页
Failure Analysis and Prevention
关键词
钛合金
螺钉
脆性断裂
缺陷
titanium alloy
screw
brittle fracture
defect
