Mechanical Behavior And Phenomenological Constitutive Of SiCp/AZ91D Under Quasi-static And Dynamic Loading

The mechanical behaviors of SiCp/AZ91 D were studied through the combination of experimental,numerical simulation and theoretical methods.The universal testing machine and SHPB were applied to the experiments.Based on the existing constitutive model combined with the experimental results,the materials parameters were determined.The yield and hardening behaviors of SiCp/AZ91 D were analized.The corresponding rate dependence were described quantitatively,and the one dimension constitutive equation was proposed.In this study,10 vol.% of 5 ?m Si Cp was added into AZ91 D alloy.The quasi-static and dynamic compressive behaviors of SiCp/AZ91 D composites were investigated through universal testing machine and SHPB,respectively.The constitutive equations was than constructed.Experimental results show that the work hardening of SiCp/AZ91 D compositecan be observed in all test conditions,which exhibits the significant rate-dependence.The exponential function was used to describe the strain rate effect on yield stress of composite.The study about hardening parameters constructed an one-dimensional constitutive equation including rate-sensitivity.The SCS was introduced to the mechanical testing of Si Cp/AZ91 D.Three bilinear constitutive models were selected to simulate mechanical behaviors i.e.the relationship of apparent load and displacement of SCS and Mises equivalent stress and strain under quasi-static and dynamic loading.Results show that: for a certain SCS with the shape and size,There is a certain relationship between the apparent load,displacement and the Mises equivalent stress,strain,which can be obtained by a appropriate data process.However,the relationship is affectedby the materials properties and loading rate.For this reason,three bilinear constitutive were applied in the numerical simulation,then the relationship between the apparent load,displacement and the Mises equivalent stress,strain can be obtained without the consideration of the materials properties.Furthermore,the unified form can be determined through the analysis of the results under different loading rates.Then the mechanical behaviors of SiCp/AZ91 D under high strain rate and large strain were investigated.The material parameters were determined based on the J-C model.The constitutive equation describe the mechanical behavior of SiCp/AZ91 D under high strain rate and large strain was proposed.