丝杠冷滚打成形过程金属流动规律研究

Study on Metal Flowing of Lead Screw Cold Roll-beating Forming

通过数值模拟与试验相结合的方法研究了丝杠冷滚打成形过程中的金属流动规律,论述了丝杠冷滚打成形原理,建立了丝杠冷滚打成形过程的数值模拟方案;根据对应力场、应变场数值模拟结果的分析,进行了丝杠冷滚打成形试验,对试验获得的丝杠工件金相组织变形、硬度分布及硬化层分布进行分析研究。结果表明:成形工件的齿槽底部最先滚打的点相比最后滚打的点变形量小;齿槽底部硬度增大,沿其底部法线方向有一定深度的硬化层,使材料硬度和强度得以提高;初步获得冷滚打过程中的金属流动规律,为进一步揭示丝杠冷滚打成形工艺的成形机理以及精确参数控制提供指导。

The metal flow of lead screw cold roll--beating torming process was studied by means of numerical simulation and experiments herein. First, the principle of the forming technology was analyzed. A FEA model of the cold roll--beating form of lead screw was built, and the stress and strain were analyzed. Then the metal flowing of the forming process was analyzed initially. Experi- ments were carried out and the metallographic structure, hardness distribution and hardening layer distribution of the obtained experimental piece were analyzed. The results show that the deformation of first roll--beating point is small compared to the deformation of last roll--beating point in the bot- tom of the tooth space. The hardness of tooth space increases. There is a certain depth of the harden- ed layer along the normal direction of tooth space. The material hardness and strength can be im- proved. These results will provide guidance for further study of the forming mechanism and precise parameter control of this new forming process.