Chaboche强化模型的使用条件及适用性

The using condition and applicability of Chaboche hardening model

基于结合Chaboche模型的ISO-KIN强化模型和Mises屈服准则,推导复杂加载模式下非线性混合强化材料模型,提出以出现反向加载来判定模拟过程中是否需要使用结合Chaboche模型的ISO-KIN强化模型的充分条件的应用原则。采用径向返回算法计算应力应变增量,实现其在有限元程序ABAQUS上进行板料塑性成形模拟的应用。以单凸型蒙皮和复杂S型蒙皮拉形工艺为例,计算不同材料强化模型对板料回弹量的影响,并与试验结果进行对比。结果表明,对于出现反向加载的复杂受力情况,相比于线性随动强化模型和各向同性强化模型,结合Chaboche模型的ISO-KIN强化模型对回弹的预测精度更高。

In this work a non-linear combined hardening law during the complicated loading condition based on the Chaboche model combined isotropic-kinematic hardening law and Mises yielding criterion has been derived. And it is pointed out that reverse loading is the criterion to decide whether to use the Chaboche type combined isotropic-kinematic hardening law or not. Return mapping algorithm was applied to calculate the stress and strain increment and a material user subroutine program was developed base on the ABAQUS interface for the model. Taking the single curve skin and complicated S-shape skin as examples, the effects of different hardening law on the spring-back in the stretch forming process was also analyzed and compared. The simulation results show that during the complicated loading condition which include reverse loading, the combined isotropic-kinematic hardening law has the better spring-back prediction compared with the pure isotropic and kinematic hardening law in the stretch forming process, which is verified by the experimental results.