Investigation On Mechanical Behavior Of Aluminum Matrix Composite With 316L Stainless Steel Hollow Spheres

As a novel material with many excellent properties,stainless steel hollow sphere aluminum matrix composite has a wide application prospect in the fields of aerospace,weapons and ships.In this thesis,the quasi-static and dynamic mechanical properties of 316 L stainless steel hollow sphere and stainless steel hollow sphere aluminum matrix composites were studied by universal testing machine and Hopkinson bar device loaded with stress wave.Through numerical simulation,the deformation behavior of stainless steel hollow spheres with different wall thickness diameter ratio under quasi-static and dynamic compression conditions has been calculated.The deformation and failure of the hollow spheres in the composite after the test were observed by SEM.The failure form and damage evolution law of the hollow spheres in the composite were studied.The following results were obtained:(1)The deformation behavior of stainless steel hollow sphere is only related to the ratio of wall thickness to diameter when the loading condition is not changed.The hollow sphere has the best performance when the wall thickness diameter ratio is 0.025.(2)Under quasi-static compression loading,the internal deformation of the composite is relatively uniform.The crack initiation point is located near the center plane perpendicular to the compression direction,and expands to both ends at 45° from the compression direction.Under dynamic compression loading,the internal deformation of the composite is non-uniformation.The degree of deformation and damage of hollow spheres is located on the center plane which is perpendicular to the compression direction However,the cracks started at both ends of the composite material under load,and also expanded along compression direction with 45 degree.(3)With increasing volume fraction of hollow spheres in composite,the yield strength and energy absorption capacity of the composites decreased,while the energy absorption efficiency of the material increased.(4)In order to investigate the effect of arrangement of hollow spheres on the properties of composite materials,the simple cubic,face-centered cubic,and body-centered cubic have been calculated.The results show that the yield strength of the composite with simple cubic arrangement is the highest,while the property of the composite with body centered cubic arrangement is the lowest,and that of the face centered cubic is between them.When the strain is a constant,the varied rule of energy absorption under different arrangement of hollow spheres in composites is the same as that of the yield strength.The body-centered cubic composite hollow sphere composite material has the highest energy absorption peak and the face-centered cubic minimum.