摘要
某6缸发动机曲轴在运行8 910km时,第六曲拐颈断裂。对断裂曲轴进行了断口观察、化学成分复验、基体硬度和显微组织检验。结果表明,曲轴的拐颈断裂为扭转疲劳断裂,断裂疲劳源位于油道孔与倒圆角曲面交接处,此处的切削加工刀痕及金属损伤形成应力集中且处于最大主应力面上,因而引发扭转疲劳断裂。
The failure happened on the sixth pitman axis after the engining crank shaft ran 8 910km. The fractured crank shaft was analyzed by fractographic inspections, chemical analysis, hardness testing of matrix and metallographic examinations. The result showed that the crack initiated from the pitman radial axis is torsioned fatigue fracture. The original crack was located at the interface of the oil hole and the filleted angle on it(a cute connected curve), where stress concentration, due to the trace of cut-machining and metal injures, occurring on the main stress section, leaded to torsioned fatigue fracture.
出处
《理化检验（物理分册）》
CAS
2005年第1期29-31,共3页
Physical Testing and Chemical Analysis(Part A:Physical Testing)
关键词
发动机曲轴
油孔倒角
金属损伤
扭转疲劳断裂
Engining crank shaft
Filleted angle on oil hole
Metal injures
Torsioned fatigue fracture
