Study On Mechanical Properties Of Particle Reinforced Magnisium Matrix Composites

Particle reinforced metal matrix composites with high specific strength,high specific stiffness and good wear resistance,good impact resistance,which excellent mechanical properties make them be widely used in aerospace,vehicle,weapons,electronic and other fields.Study found that,the mechanical properties of particle reinforced metal matrix composites will be affected by many factors,such as the preparation technology,components of the selected materials,the shape of particle,average size of particle,volume fraction,degree of partial poly,interfacial bonding situation between particles and matrix,and heat treatment process could produce a larger difference.The SiCp/AZ91 D magnesium matrix composites were investigated in this paper,introduced the thermal residual stresses caused by the difference of thermal expansion coefficient between matrix and enhancement phase,random particle model was established based on the finite element software,analyzed the effect of thermal residual stress of the composite materials on particle shape,particle size and particle mass fraction in the process of cooling,and analyzed the incidence of various factors on the thermal residual stress.Nanoindentation was used in this study to investigate the elastic modulus,hardness,load,and contact stiffness of SiC particle-reinforced AZ91 D composites and each relations between them.In addition,the flow stress characteristic of the composite material is measured by the split Hopkinson pressure bar,explained the mechanism of strength increased of silicon carbide particle reinforced composites,analyzed the mechanism of different strain rate sensitivity on quasi-static loading and high speed loading at the condition of plastic deformation.The adiabatic temperature rise was calculated under different strain rate,the flow stress curve was obtained with the uncorrected and modified Johnson-Cook model,comparing the experimental results with the calculated ones,we can know the adiabatic temperature rise and its impact on the constitutive equation.