介观尺度下热成形板料与模具对摩过程有限元模拟

Finite element simulation of friction process between sheet metal and die in hot forming in mesoscale

基于高温单向摩擦实验过程,提出一种介观尺度下对摩过程中的有限元模型,分析了介观条件下的实际接触条件。结果表明:接触表面的起伏造成对摩过程的有限元模型计算所得的摩擦因数在设定的摩擦因数上下范围内变动。由于实际接触面积比名义接触面积小,在滑移过程中,接触材料发生变形导致接触面积变小,且上下表面起伏导致的在滑移中的碰撞使得局部接触压强比摩擦滑块的名义压强大。滑移过程中界面之间的接触压强大于名义压强且沿着滑移方向呈阶梯式分布。

Based on high temperature unidirectional friction experiment process,a finite element model of friction process in mesoscale was proposed to analyze actual contact conditions under mesoscopic conditions.The results show that the friction factor calculated by the finite element model in friction process varies within the range of the set friction factor due to the fluctuation of contact surface.Because the actual contact area is smaller than the nominal contact area,the contact area becomes smaller due to the contact material deformation in the sliding process,and the collision of the upper and lower surfaces in the sliding process causes that the local contact pressure is greater than the nominal pressure of the friction slider.The contact pressure between the interfaces is greater than the nominal pressure and the distribution along the sliding direction is stepped during sliding process.