Study On The Effect Of Nior Tion Microstructure And Properties Of Magnesium-based Composites

Magnesium-based composites have high specific strength and specific modulus,good wear resistance and corrosion resistance,etc.They are light metal matrix composites with excellent performance developed after aluminum-based composites,and they have a broad development prospect in aerospace,automobile industry,electronic communication and other fields.In our country,magnesium resources are abundant.Nowadays,with the depletion of limited energy sources on earth,accelerating the research and development of magnesium materials is one of the important measures to realize the effective utilization of resources and sustainable development strategy in China.In this paper,Mg,Sb,Ni,and Ti powders were used as raw materials.?Mg₂Ni+Mg₃Sb₂?/Mg composites and?Ti+Mg₃Sb₂?/Mg composites were prepared by powder metallurgy.The effects of the addition of Ni or Ti on the phase composition,microstructure,mechanical properties and friction and wear properties of magnesium-based composites were studied by changing the composition ratio and sintering temperature of the composites.The results show:?1?The hot pressing plastic deformation of the composite can eliminate the defects such as holes in the material,improve the density of the composite,improve the distribution uniformity of the structure,and improve the strength and hardness of the composite.?2?With the increase of Ni contents or Ti contents,the microhardness of?Mg₂Ni+Mg₃Sb₂?/Mg and?Ti+Mg₃Sb₂?/Mg composites increases gradually,and the tensile strength increases first and then decreases.When w_Sb=15%and w_Ni=7.5%,the mechanical properties of?Mg₂Ni+Mg₃Sb₂?/Mg composites are the best.The average values of hardness and strength of?Mg₂Ni+Mg₃Sb₂?/Mg composites are about 33%and 20%higher than that of Mg₃Sb₂/Mg composites respectively.When w_Sb=15%and w_Ti=10%,the mechanical properties of?Ti+Mg₃Sb₂?/Mg composites are the best.The average values of hardness and strength of?Ti+Mg₃Sb₂?/Mg composites are 23%and34%higher than that of Mg₃Sb₂/Mg composites respectively.?3?The microstructure and mechanical properties of?Mg₂Ni+Mg₃Sb₂?/Mg composites and?Ti+Mg₃Sb₂?/Mg composites are different with the change of sintering temperature.When the sintering temperature is 700?,the microstructure and mechanical properties of?Mg₂Ni+Mg₃Sb₂?/Mg composites and?Ti+Mg₃Sb₂?/Mg composites are well distributed and the best.?4?When the load and frequency are fixed and other experimental conditions are the same,the volume wear rate of?Mg₂Ni+Mg₃Sb₂?/Mg composites and?Ti+Mg₃Sb₂?/Mg composites decreases with the increase of Ni content or Ti content.when the load is fixed and other experimental conditions are the same,the volume wear rate of?Mg₂Ni+Mg₃Sb₂?/Mg composites and?Ti+Mg₃Sb₂?/Mg composites increases with the increase of friction frequency.The wear mechanism of materials is different under different experimental conditions.