汽车结构件低载强化的微观分析  

Microscopic Mechanism of Automobile Structure Strengthening under Low Amplitude Load

作　　者：郑松林[1] 卢曦[1] 马晓婷[1] 

机构地区：[1]上海理工大学机械工程学院,上海200093

出　　处：《机械工程材料》2006年第7期29-32,共4页Materials For Mechanical Engineering

基　　金：国家自然科学基金(50375101);上海汽车工业科技发展基金(0329)

摘　　要：为了从微观上解释汽车构件低载强化产生的原因,利用透射电镜对汽车前轴低载强化前后微观组织特征进行了深入研究。结果表明：经过低载强化后,造成材料晶界附近位错高度缠绕,形成位错墙；晶粒变形时的晶界摩擦力增大,晶内的晶胞原子结合更紧密,在高载荷的反复作用下晶格常数仍能基本保持不变,晶界强化则是低载强化微观上的主要原因。In order to study the microscopic mechanism of strengthening under low amplitude loading, microstructure was investigated using transmission electron microscopy. The specimens were got from truck front axle. After strengthened under low amplitude loading, the wall of dislocation was formed along the grain boundary, resulting in the increases of the friction near the grain boundary when the grain was deformed, and closer combining of the cells. The lattice constants were kept constant under cycled high load. Those explained the mechanism of strengthening under low amplitude loading microscopically.

关 键 词：微观组织分析 位错 低载强化 疲劳强度 

分 类 号：U463.3[机械工程—车辆工程]