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Abstract：
In this article, a response of the complex-phase high-strength steel SZBS800 was modelled by considering the strain-rate influence. The material\'s response was first measured with a series of standard tensile tests at lower strain rates. Higher strain rates were achieved using the unconventional test of shooting the ball into flat specimens. A viscoplastic formulation of the Cowper-Symonds material model was applied to consider the strain-rate effects. The parameters SIGY, p, and C of the material model were estimated using a step-wise procedure. First, rough estimates of the three parameters were obtained from the tensile tests using the grid search method. Then, the parameters p and C were fine-tuned using the reverse engineering approach. With the help of explicit dynamic simulations and all the experimental data, a multi-criteria cost function was defined and applied to obtain a smooth response function for the parameters p and C. Its optimum was determined by a real-valued genetic algorithm. The optimal values of the estimated parameters model the material response well, although a domain of optimum candidates spans two orders of magnitude for the parameter p and a few orders of magnitude for the parameter C.
摘要：
在这篇文章中,通过考虑应变率影响，模拟了复相高强度钢SZBS800的响应。首先用一系列标准拉伸试验在较低的应变率下测量材料的响应。使用将球射入平坦试样的非常规测试可获得更高的应变率。应用Cowper-Symonds材料模型的粘塑性公式来考虑应变率效应。参数SIGY，p,材料模型的C和C是使用逐步程序估计的。首先,使用网格搜索方法从拉伸试验中获得了三个参数的粗略估计。然后，使用逆向工程方法对参数p和C进行了微调。在显式动态模拟和所有实验数据的帮助下，定义了多准则成本函数，并将其应用于获得参数p和C的平滑响应函数。估计参数的最优值很好地模拟了材料响应，尽管最佳候选域跨越参数P的两个数量级和参数C的几个数量级。
