SMA复合材料低速冲击数值模拟方法

利用形状记忆合金(shape memory alloy,SMA)独特的超弹性效应,提出一种利用形状记忆合金提高复合材料结构抗低速冲击性能的方法.基于形状记忆合金的分段化线性简化模型,利用ABAQUS有限元软件提供的VUMAT子程序编制了SMA合金超弹性本构关系并将其引入到复合材料层板低速冲击模型,提出了含SMA复合材料低速冲击数值模拟方法.研究形状记忆合金利用迟滞阻尼特性吸收部分形变能量并加以释放的过程,探讨SMA纤维对复合材料层板抗冲击性能的增强规律.结果表明,随着SMA体积分数的提高,复合材料层板的冲击应力峰值和挠度会下降,但在低SMA体积分数(<10%)情况下,对挠度的改善作用不明显;同时随着SMA体积分数增加,单位体积SMA的冲击能量吸收率会降低,在SMA体积分数为5%~10%时,SMA纤维具有最高的能量吸收率.得出了SMA纤维具有改善复合材料抗冲击性能的作用的结论. 

Numerical simulation method of low-velocity impact on SMA composite material

A method of improving the ability of low velocity impact resistance of composite material by using the super elastic property of shape memory alloy (SMA) was proposed. Based on the segmented linearization model of SMA and its simplified assumption, SMA super elastic constitutive model was developed by the VUMAT subroutine of ABAQUS. The numerical simulation model of low velocity impact of SMA reinforced composite material was established by ABAQUS to study how SMA absorb and discharge part of deformation energy by using hysteresis damping. Results show that the peak value of impact stress and the deflection of composite material decrease with the increase of SMA volume fraction, but the improvement of the deflection is not obvious at low SMA volume fraction (<10%). With the increase of SMA volume fraction, the impact energy absorption rate of SMA per unit volume decreases, and the SMA fiber has the highest energy absorption rate in the SMA volume fraction of 5%-10%. Numerical result shows that SMA fiber can effectively improve low velocity impact response performance of composite material.