基于局部应力应变法的弧齿锥齿轮锻造模具寿命预测

Service Life Prediction of Forging Die of Spiral Bevel Gear based on Local Stress and Strain Method

模具寿命是影响弧齿锥齿轮锻造成本的主要因素之一。采用弹塑性有限元模型,对弧齿锥齿轮热锻成形的模具应力分布进行了模拟仿真,基于局部应力应变法,从模具的预热温度、齿模齿顶的过渡圆弧半径以及锻造成形速度等工艺因素计算模具的应力应变分布,分析各工艺因素对模具寿命的影响规律。模拟结果表明,热锻成形的弧齿锥齿轮的模具失效形式,主要为齿模的齿顶和齿根处应力集中引起的断裂。对于齿模的齿顶位置来说,三种工艺参数的变化与齿模疲劳寿命成正比。对于齿模的齿根位置来说,工艺参数的变化与模具寿命成反比。提出的模具寿命预测方法为批量化生产中优化模具结构和预测模具寿命提供了技术参考。

Die service life is one of the important factors in influencing the forging cost. The die stress distribu- tion is simulated by using elasto- plastic finite element model. Based on the local stress and strain method, the die stress distribution is calculated from three process factors, which are the addendum transition arc of tooth die, the forming velocity and initial die temperatures, the influence law of these process factors is analyzed. From the simula- tion results, tooth die stress concentration positions are located in the tooth tip and tooth toe of tooth die, and it is the main failure mode. As to the addendum of tooth tip, the die service life is direct proportional to the three process fac- tors, to the dedendum of the tip and toe, the die service life is reverse proportional to the mentioned process factors. The method of prediction die service life concerned in this research provides technical reference in mass production.