时效对多胞铝合金薄壁结构压缩变形行为的影响

Effect of aging treatment on axial collapse behaviors of aluminum alloy with multi cell thin-walled structure

以6063铝合金多胞薄壁梁结构为研究对象,采用准静态轴向加载的方式,借助WAW-E600型微控万能试验机,探明时效处理对铝合金薄壁梁压缩变形行为与吸能性能的影响规律。结果表明:随着时效处理时间的延长,6063铝合金多胞薄壁梁试样的变形模式逐渐由欧拉模式转变为手风琴模式,试样的峰值载荷、名义载荷与吸能性能也逐渐提高;针对载荷-位移曲线进行二阶求导获得结构临界失稳载荷,运用Slogistic函数拟合研究时效处理对试样承载性能的影响规律;基于T-Student相关性参数评估方法,通过主因子相关性分析引入Ramberg-Osgood硬化指数n(n为变量),建立峰值载荷、名义载荷、可压缩变形量及吸能性能的二次多项式拟合模型,该模型能够准确预测不同时效处理状态下6063铝合金薄壁梁结构的弹塑性变形行为,为铝合金车身结构的概念设计提供理论指导。

The effect of heat treatment on collapse behaviors and energy absorption of 6063 aluminum alloy with multi cell thin-walled structure was investigated by quasi-static axial compression using WAW-E600 microcomputer controlled universal testing machine. The results show that the deformation mode of the 6063 aluminum alloy with multi cell thin-walled structure changes from Euler mode to concertina mode with the increase of aging time, while the peak load, mean load and energy absorption of the sample also enlarge. The critical buckling load of the structure is obtained by the second order derivation of the load-displacement curve. The influence of aging treatment on the bearing performance of the specimen was studied by Slogistic function fitting. Based on the T-Student evaluation method, the Ramberg-Osgood hardening parameter n is introduced as a variable by the main effect analysis. The quadratic polynomial fitting models of peak load, mean load, collapsed length and energy absorption performance were established. The models can accurately predict the elastic-plastic deformation behavior of 6063 aluminum alloy thin-walled structure under different aging conditions, which can provide theoretical guidance for the conceptual design of aluminum alloy automotive body.