摘要
某电机作动筒支臂材料为40Cr钢,在支臂系统测试过程中支臂发生断裂。通过外观检查、断口观查、金相检验和硬度检测等方法,确定了支臂断裂性质和断裂原因。结果表明,电机作动筒支臂断裂性质为脆性过载断裂;支臂调质不良,材料中出现大量铁素体,支臂脆性增大,同时内壁存在脱碳层以及壁厚不足降低了支臂的承载能力是导致其过载断裂的内因;支臂工作过程中存在不均匀受力以及冲击载荷是导致其断裂的外因。通过热模拟试验讨论了支臂不良组织产生原因,并提出了预防措施。
An actuator cylinder arm made of 40Cr steel was broken during the arm system tested. The feature and cause of the arm were analyzed by visual inspection, fracture view, metallographic examination and hardness testing. The results show that the fracture mode of the actuator cylinde arm is brittle overload fracture. Undesirable quenching and tempering cause a large number of ferrite existing in materials, which make brittleness of arm increasing, meanwhile decarburized layer existing inside wall, and the lack of the wall thickness reducing the carrying capacity of the arm are the internal reasons to overload fracture. Uneven force and impact load during the running of the arm are the external factors. The reasons that harmful structure of the arm are discussed by thermal simulation, and counter measures are proposed.
出处
《金属热处理》
CAS
CSCD
北大核心
2015年第6期199-203,共5页
Heat Treatment of Metals
关键词
作动筒支臂
40CR钢
脆性过载断裂
actuator cylinder arm
40Cr steel
brittle overload fracture
