工艺参数对高强度钢冷冲压界面温度影响分析

为探究先进高强度钢冷冲压成形过程中板料-模具界面温度场变化,以DP590钢板U形件冷弯曲过程为研究对象,采用热力耦合有限元静力算法建立弯曲过程的数值仿真模型,完成了板料-凹模圆角区界面温度场数值模拟,分析了相对圆角半径、压边力、拉伸速度和摩擦系数对界面温度峰值的影响.研究表明:随着模具相对圆角半径减小、拉伸速度增大、摩擦系数增大,板料-凹模圆角区界面温度峰值明显增加;压边力对瞬态阶段界面温度峰值没有明显影响,而稳态阶段界面温度峰值随压边力增加而增大,当压边力压实变形板料后其峰值逐渐趋于稳定.

Numerical Analysis of the Effect of Processing Parameters on#br# Temperature on the Contact Interface During#br# High Strength Steel Cold Stamping

In order to study temperature field on the interface between die and blank at die radius zone during cold sheet forming, the temperature field during DP590 sheet U shaped bending was calculated by using a thermo mechanical coupled static implicit finite element model, and then the influences of the four key processing parameters (relative radius of die, blank holder force, forming velocity, and friction coefficient) on the maximum value of the temperature field were analyzed. The investigation shows that the maximum temperature on the interface increases with the decrease of the relative radius of die, the increase of the forming velocity and the increase of the friction coefficient, respectively. Blank holder force has obviously different influence in different forming phase: in the initial transient phase, the blank holder force has almost no influence on the maximum temperature, while in the steady phase, the maximum temperature increases with the increase of the blank holder force in a certain range, but once the force comes above this range, the max value does not increase with the blank holder force.