Dry Friction Behavior Of Mg-xAl(Zn,Si,Ca)binary Magnesium Alloys

As a new type of lightweight metal material,magnesium material has the advantages of high specific strength,good casting and processing performance,etc.,and has become an important material in the fields of automobiles,aviation,and electronic products.With the continuous expansion of application fields,people have higher and higher requirements for the performance of magnesium alloys,and wear resistance has attracted much attention as one of the important properties during use.At present,the research on the wear resistance of magnesium alloys mainly focuses on multicomponent magnesium alloys.The alloying elements in magnesium alloys have the solid solution and precipitation strengthening effects.The precipitation phase is usually a metal compound formed by multiple elements.It is difficult to distinguish the influence of a single element on the Mg matrix.In order to study the effect of alloying elements on the wear resistance of magnesium alloys,and to describe the effects of solid solution strengthening and precipitation strengthening in magnesium alloys on the friction mechanism of Mg matrix,it is necessary to carry out research on the tribological behavior of binary magnesium alloys with different element contents.At the same time,the qualitative and quantitative analysis of the effect of alloying elements on the wear resistance of Mg matrix will provide experimental and theoretical support for the composition design of multicomponent wear-resistant magnesium alloys.The application of magnesium alloys is inseparable from the casting and heat treatment process.Appropriate magnesium alloy casting methods can refine the grains,improve the surface quality of the alloy,and improve the wear resistance of the alloy.Heat treatment can further increase the solid solubility of alloying elements,cause lattice distortion,increase dislocation resistance,and at the same time refine grains and enhance the wear resistance of the alloy.In order to study the effect of alloying elements on the wear resistance of binary magnesium alloys,how to make the solid solution and precipitation uniform becomes the key to the selection of casting and heat treatment processes.To this end,this paper selects metal mold gravity casting to prepare Mg-x Al,Mg-x Zn,Mg-x Si,Mg-x Ca magnesium alloys,adopts solution and artificial(natural)aging method for heat treatment,and analyzes the changes of alloy hardness and microstructure.On this basis,the dry friction behavior of binary magnesium alloys was studied,the effects of solid solution and precipitation strengthening on the tribological properties of Mg matrix were analyzed,and the tribological mechanism of magnesium alloys was expounded.At the same time,according to the tribological test data of Mgx Al and Mg-x Zn binary magnesium alloys,the mathematical relationship between multi-element AZ magnesium alloy elements and wear resistance was established.The research of this topic will provide experimental data for the effect of alloying elements in multi-element magnesium alloys on the wear resistance of Mg matrix,improve the theoretical system of tribology under dry friction of magnesium alloys,and provide a basis for the composition design and engineering of lightweight wear-resistant magnesium alloys.The application provides theoretical guidance.