热锻模工艺参数与模腔表层温度分布关系的模拟研究

常规热锻模的损伤主要原因是由于模具表层温度分布所引起的温度应力.模具表面所达到的最高温度和热渗透深度是预测损伤方式和确定表面处理或涂层厚度及性质的两个基本参数.以热锻轮毂的下模为例,用Deform 2D软件对表层温度分布进行了系统的模拟分析,研究了坯料温度、压力机速度、摩擦因子、模具初始状态对模具表层最高温度及高热流密度热渗透深度的影响并将所得的数据利用OrginPro软件进行拟合,找出其变化规律.结果表明:在热锻生产过程中,合理的选择加工工艺参数,能有效的降低模具表层温度,防止模具因表层软化而失效;通过表面技术来提高热锻模具寿命,应确保模具表面涂覆硬化层深度大于其热渗透层深度.

Simulation Analysis on Relationship Between Hot Forging Process Parameters and Die Cavity Surface Temperature Distribution

The thermal stress on the surface of hot forging die mainly leads to the damage of common hot forging die.The maximum surface temperature and thermal penetrating depth in die cavity predicting die damage styles,superficial treatment,as well as properties.are the fundamental parameters.The model of wheel hub lower die as an example was simulated on its surface temperature distribution under Deform 2D software.The effects of blank temperature,frictional coefficient,velocity of forging press and original condition of dies on the maximum surface temperature and penetrating depth of high thermal flow density were investigated.The obtained data were then put into OrginPro so as to find out the rules.The results show that,in the process of hot forging,the surface temperature of dies could be availahly decreased by adopting optimized parameters in order to prevcnt the failure of hot forging die caused by the surface softening;and for the purpose of increasing service lifetime of hot forging dies with superficial treatment,it must be considered that the depth of hardened-layer ofcoating is deeper than that of the thermal penetrating-layer.