泡沫铝材料压缩力学特性及本构模型研究

Research on compressive mechanical properties and constitutive model ofaluminum

为研究泡沫铝材料的力学特征及其本构模型.利用材料试验机对泡沫铝材料进行准静态压缩力学性能试验,从而得到泡沫铝不同孔径、孔隙率的应力应变曲线·拟合得到该型材料的本构模型,并分析孔径、孔隙率对其力学性能的影响规律。结果表明:泡沫铝的屈服强度与流动应力随着相对密度的增大而增加.压缩至致密段的最大应变量随着相对密度的增大而减小。泡沫铝的弹性模量与孔径大小无关,屈服强度与孔径大小相关。塑性模量受孔径的影响较大。通过曲面拟合,得出该材料的弹性模量、屈服强度的函数表达式,为后续泡沫铝材料的应用提供基础数据。

In order to study the mechanical properties and constitutive model of aluminum foam,the stress-strain curves of different aperture and porosity of aluminum foams has been studied and compared by MTS material testing machine to the quasi-static compressive mechanical test.The constitutive model of the material has been obtained by fitting the test result.The results show that,as the relative density increases,the yield strength and flow stress of aluminum foam increase,the maximum strain of compression to the tight section decreases.The elastic modulus of aluminum foam is independent of aperture.Yield strength is related to aperture.The mold modulus is greatly affected by the aperture.The function expressions of elastic modulus and yield strength has been obtained by curve fitting method.lIt provides the foundation for the subsequent applicationofaluminumfoam.