材料参数对3A21矩形管弯曲回弹的敏感性分析

Sensitivity analysis of material parameters on spring-back of 3A21 aluminum alloy rectangular tube in the bending process

为了解材料参数波动对3A21铝合金薄壁矩形管弯曲回弹的影响,基于动态显式有限元软件ABAQUS,借助多因素敏感性分析方法,建立了薄壁矩形管弯曲回弹敏感性分析模型,对材料参数影响回弹的规律进行了敏感性分析.结果表明:弹性模量是影响3A21薄壁矩形管回弹最敏感的因素,其次分别为强度系数、初始屈服应力及硬化指数;弹性模量对回弹角与回弹半径的敏感度因子分别高达0.8872与0.9585;当弹性模量的输入值与实际值相差15%时引起的回弹角与回弹半径的相对误差分别为13.31%与14.38%,同时分别获得了强度系数、初始屈服应力及硬化指数存在15%的误差时引起的回弹角与回弹半径的相对误差值.通过敏感性分析剔除了非敏感因素,简化了材料参数对薄壁矩形管弯曲回弹影响的分析过程.

To study the influence of material parameters on spring-back of 3A21 aluminum alloy thin-walled rectangular tube,a sensitivity analysis model is established based on ABAQUS and the multi-parameters sensitivity analysis method.The results show that： 1）The elastic modulus E is the most sensitive parameter for the spring-back,while the strength coefficient K,initial yield stress σs and strain hardening exponent n have a less influence on spring-back;2）The sensitive factors of elastic modulus E for the spring-back angle and spring-back radius could reach to 0.8872 and 0.9585,respectively;3）The relative error of spring-back angle δΔθ and spring-back radius δΔR could reach to 13.31% and 14.38% when the discrepancy between the input value and true value of elastic modulus E is 15%.Meantime,the relative error of spring-back angle and spring-back radius caused by the error of strength coefficient K,initial yield stress σs and strain hardening exponent n are obtained.