冷挤压塑性流体动力润滑分析

A Plasohydrodynamic Lubrication Analysis during Cold Extrusion

应用流体动力润滑理论和塑性成形原理,分析了冷挤压润滑过程,在挤压的起始和终止阶段为非稳态流体动力润滑,而中间阶段可近似为稳态流体动力润滑。考虑冷挤压在高压及大剪切应变率工况下润滑剂的非牛顿特性,运用Ostwald非牛顿体模型,分别建立了冷挤压非稳态和稳态的塑性流体动力润滑(PHD)模型。采用Monte Carlo法得到了冷挤压润滑过程的油膜厚度、油膜压力以及摩擦力的分布规律。

The process of hydrodynamic lubrication during cold extrusion was analyzed by means of theory of hydrodynamic lubrication and metal forming. The mechanism of lubrication was studied,which is unsteady and steady plastohydrodynamic lubrication. In the light of the non-Newtonian feature of lubricant under the condition of high pressure and large shearing strain ratio during the cold extrusion, the mathematics models of unsteady and steady plastohydrodynamic lubrication in cold extrusion were established respectively by Ostw＇ald non-Newtonian model. The distribution of lubricant film thickness and stress during cold extrusion was calculated by Monte Carlo method.