摘要
本文从微观入手对金属压力成型过程中摩擦的形成原因进行了分析 ,认为摩擦主要是由于被压入工具表面凹坑金属的塑性流动所引起的。摩擦功率等于此部分金属的变形功率 ,当它的变形功率大于在界面产生剪切流动的功率时 ,摩擦由滑动摩擦转变为粘着摩擦。同时 ,根据对工具表面的某些假设 ,推导了摩擦应力与粗糙度和静水压应力等之间的关系 ,并求出了发生粘着摩擦所需的静水压应力。计算结果表明 ,建立的摩擦模型是比较有效和合乎实际的 。
In this article,the reason how the friction produces in the process of metal forming was analyzed,and the friction was thought to be mainly caused by the plastic flow of metal in the pits of tool surface.The work rate of the metal in pits was considered to be the frictional work rate,and when the work rate was great than the work rate to produce shear flow at the interface between the metal and tool,the friction was thought to change into sticky friction from slide friction.According to some hypothesis about tool surface,the relationship among the friction,roughness and hydrostatic stress was derived,and the limited hydrostatic stress was got when the sticky friction takes place.The result of calculation showed that the frictional model was effective and closed to fact,and a new method was provided to calculate the friction in theory.
出处
《塑性工程学报》
CAS
CSCD
2000年第4期29-32,共4页
Journal of Plasticity Engineering
