Experimental and numerical study of the impact behavior of SMC plates
Experimental and numerical study of the impact behavior of SMC plates
复制标题
SMC板冲击行为的实验与数值研究
DOI：
10.1016/s0263-8223(00)00021-0
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发表时间：
1999
期刊：
影响因子：
--
通讯作者：
Y. Im
中科院分区：
文献类型：
--
作者：
Sangmin Lee;J. Cheon;Y. Im
钢构件通过塑性变形吸收冲击能，复合材料通过纤维脱粘、纤维断裂、基体开裂等损伤机制吸收冲击能。因此，为了在工业应用中适当地用复合材料代替金属部件，必须了解复合材料的冲击性能。摘要以SMC为研究对象，对其冲击性能进行了实验研究和数值模拟。SMC是一种成本低、生产率高、在汽车工业中得到广泛应用的复合材料。为了研究SMC的冲击性能，建立了落锤冲击试验系统，对其进行了试验研究。利用该系统测量了SMC平板的耗散冲击能，研究了冲击器的质量、形状、初始速度和试样厚度对冲击行为的影响。为了进行数值预测，开发了一种修正的SMC损伤模型，并将其应用于商用仿真程序LS-DYNA3D的用户自定义材料子程序中。为了提高冲击模拟的效率，考虑了纤维体积分数的局部差异，确定了SMC材料的性能。通过预测数据与实验结果的比较，验证了不同条件下的冲击耗散能和所开发的冲击模拟过程的可靠性。通过对比发现，在目前的研究范围内，试件厚度是SMC构件在冲击性能方面设计时应考虑的最重要参数。
Steel components absorb impact energy by plastic deformation whilst composite materials absorbing it by damage mechanisms such as fiber debonding, fiber fracture, and matrix cracking. Therefore, in order to properly substitute metal components with composite ones in industrial applications, the impact property of composite materials must be well known. In this study, the impact behavior of sheet molding compounds (SMC), which is widely used in automobile industry due to its relatively low cost and high productivity, was examined both experimentally and numerically. In order to investigate the impact behavior of SMC, an experimental study was carried out by setting up a drop weight impact test system. Using this system, the dissipated impact energies of SMC flat plates were measured to investigate the influence of the mass and shape of impactor, initial velocity, and specimen thickness on the impact behavior. For numerical predictions, a modified damage model for SMC was developed and adopted in the user defined material subroutine of the commercial simulation program LS-DYNA3D. For the sake of improving efficiency of impact simulations, the SMC material property was determined in consideration of the local differences of the fiber volume fractions. The dissipated impact energies under various conditions and the reliability of the developed impact simulation process were examined through comparisons of the predicted data with the experimental results. From this comparison, it was found that, in the scope of current study, the specimen thickness is the most important parameter that should be considered in the design of SMC components for the aspect of impact behavior.