基于响应面法的铝合金自冲铆接头强度预测模型

Strength prediction model of self-piercing riveted joints of aluminum alloy based on response surface method

采用Box-Behnken Design试验设计方法,针对多种材料开展铝合金自冲铆接头的静力学试验研究。以接头的失效载荷作为目标量,被连接材料硬度、板材厚度、铆钉硬度以及各参数之间的交互作为影响目标量的因素,建立铝合金自冲铆接头强度预测的非线性多元回归模型。试验验证结果表明:建立的非线性多元回归模型具备高的显著性且拟合程度高,可实现对铝合金自冲铆接头强度的有效预测,模型预测结果与实际值的相对误差在7%以内,且方差分析表明,随着材料硬度增加,失效载荷先减小而后增大;板材厚度对接头失效载荷的影响呈正线性相关性;铆钉硬度对接头失效载荷的影响呈负线性相关性。

Based on the Box-Behnken Design( BBD) test design method,static tests study of aluminum alloy self-piercing riveted joints were carried out for various materials. The failure load of the joints was taken as the target quantity. The connected material hardness,sheet thickness,rivet hardness and the interaction between the parameters were defined as the influence factors of the target quantity. A nonlinear multiple regression model was established to predict the strength of aluminum alloy self-piercing riveted joint. The test verification results show that the established nonlinear multiple regression model has high saliency and high fitting degree,which can effectively predict the strength of aluminum alloy self-piercing riveted joint. The relative errors between the prediction results of the model and actual results are less than 7%. Variance analysis shows that the failure load first decreases and then increases with the increase of material hardness. The influence of sheet thickness on failure load of joint is positively linear correlation. The influence of rivet hardness on failure load is negatively linear correlation.