多变载荷下板料成形摩擦系数模型的试验研究

Experimental Study on Friction Coefficient Model in Sheet Metal Forming under Variable Loads

采用MPX-2000盘销式摩擦试验机研究了边界润滑条件下不同界面载荷对304不锈钢与SKD11模具钢之间摩擦系数的影响。运用matlab软件对试验数据进行处理分析,建立了一个基于不同界面载荷的变摩擦系数模型。并对变摩擦系数模型和定摩擦系数模型进行了有限元模拟及试验验证,比较了回弹预测结果与试验测量值的误差。结果表明:摩擦系数随正压力从0.510~7.643 MPa的不断递增而逐渐减小;变摩擦系数模型的回弹预测结果与测量值之间误差较小,验证了变摩擦系数模型的有效性。

The effects of different interface loads under boundary lubrication condition on the friction coefficient of 304 steel plate and SKD11 die steel were studied by adopting MPX-2000 disc-on-pin wear tester. The test data were studied by Matlab software. The variable friction coefficient model based on different interface load was established. The changed friction coefficient model and constant friction coefficient was simulated by finite element, then the test verification was carried out. The errors of springback predicted results and the measure values were compared.The results indicate that the friction coefficient decreases with the increase of the normal load from 0.510 MPa to 7.643 MPa. The error between the predicted results and the measured values of the variable friction coefficient model is less, which can verify the validity of variable friction coefficient model.