基于多项式代理模型的薄膜材料力学参数识别

Mechanics parameter identification of thin film materials based on polynomial proxy model

针对鼓泡方法对具有不同本构关系的薄膜材料力学参数识别方法难以统一的问题,提出了一种基于代理模型的薄膜材料力学参数识别方法。首先,运用多项式代理模型将薄膜材料力学参数与薄膜试件在不同测点的挠度仿真值之间的关系显式化,然后采用改进的鼓泡实验装置测量并获得薄膜试件上各测点的扰度实验值,再以相应的测点多项式代理模型值与实验值之间的相对误差的平方和作为目标函数,采用状态转移算法对材料参数进行反解,获得能表征薄膜的真实材料参数。采用这一方法,对304不锈钢薄膜和橡胶材料进行识别实验,证实了这一方法的有效性和可靠性。因此可以利用本文的方法研究鼓泡实验装置的仪器化,从而为进一步实现薄膜材料力学参数识别方法的统一提供新的思路。

In order to solve the difficulty in unifying the methods for identifying mechanical parameters of thin film materials with different constitutive relations by the bubbling method, a method based on polynomial proxy model for identifying mechanical parameters of thin film materials is proposed. Firstly, the polynomial proxy model is used to show the relationship between the unknown mechanical parameters of thin film materials and the simulated deflection values at different measuring points on the thin film specimens. The experimental values of the deflection at different measuring points on the thin film specimens are obtained by using the improved bubbling device. Then, the inverse problem model is constructed by taking the sum of squares of the difference between the experimental values and the corresponding polynomial proxy model at measuring points as the objective function. Finally, the state transition algorithm is used to reverse the material parameters and obtain the real material parameters which can characterize the thin film. In this work, the 304 stainless steel thin films and the rubber materials are taken as examples to identify the effectiveness and reliability of this method. The numerical results show that the inversion method based on polynomial proxy model has a strong ability to identify the unknown parameters of thin film materials, and can identify all the constitutive parameters of thin film materials at one time. The calculation efficiency and recognition accuracy are both superior.