摘要
基于等刚度理论设计了以聚乳酸为材料的某款电动车蓄电池托盘。通过拓扑优化,在使托盘质量减轻8.5%的同时,托盘的最大应力和最大位移分别减小了26.5%和19.7%。考虑到非金属材料的蠕变特性,以时间硬化理论为基础建立材料蠕变模型,通过有限元分析,得到零件在长期受载情况下的蠕变应变值。结果表明,聚乳酸材料零件满足产品在尺寸稳定性上的设计要求,验证了聚乳酸材料在汽车产品应用中的可行性。
The battery tray of polylactic acid in an electric vehicle is designed based on equal stiffness theory. Through topology optimization the maximum stress and displacement of battery tray reduce by 26.5% and 19.7% respectively while its mass drops by 8.5%. With consideration of the creep characteristics of nonmetallic materials, the creep model of the material is established based on the theory of time hardening, and a finite element analysis is conducted to get the creep strain of battery tray under long-term loading condition. The results show that polylactic acid parts meet the design requirements of product in terms of dimension stability, verifying the feasibility of the application of polylactic acid to automotive products.
引文
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