摘要
某微型面包车用发动机曲轴在运行14560km时,第一曲拐靠近曲柄销处发生断裂。对断裂曲轴进行了断口观察、化学成分复检、基体硬度和显微组织检验。结果表明,该断裂为扭转疲劳断裂,其因是曲柄与曲柄销间的过渡圆角过小,以及圆角表面残留的切削刀痕,曲轴工作过程中此处形成应力集中,因而引发扭转疲劳断裂。
When a micro minibus ran in 14560 kM,the fracture occurred at the first crank near crankpin. The inspection of crankshaft break, analyses of chemical elements, matrix hardness test and microstructure observation were done. The results showed that the failure is torsional fatigue fi-acture, which takes place as too small knuckle and some residual tool marks, and so stress concentration leads to torsional fatigue fracture finally.
出处
《热加工工艺》
CSCD
北大核心
2009年第17期148-149,共2页
Hot Working Technology
关键词
曲轴
过渡圆角
扭转疲劳断裂
crankshaft
knuckle
torsional fatigue fracture
