Effect Of Grain Refiner On Microstructure And Properties Of AZ52X Magnesium Alloy

The purpose of this paper is to replace the aluminum alloy components of UAV power housings with magnesium alloys to make them lightweight.With Mg-5Al-2Zn-0.5Ca as matrix,different content of grain refiners Al-Ti-B and Al-Ti-C were added,and a new type of magnesium alloy with good mechanical properties was casted by metal mold.The microstructures of the prepared alloys were analyzed by optical microscopy?OM?,scanning electron microscopy?SEM?,and X-ray tester?XRD?,and tested by Brinell hardness tester,Vickers hardness tester,and electronic universal tester.The prepared alloys were tested for mechanical properties in order to meet the requirements of strength,and the effects of Al-Ti-B and Al-Ti-C on the microstructure and mechanical properties of the alloys were investigated.The processed raw materials were compounded according to the preset composition,and were smelted in an electric resistance furnace.Different levels of grain refiners Al-Ti-B and Al-Ti-C were added according to the single factor variables.When a certain amount of Al-Ti-B and Al-Ti-C are added to the AZ52X alloy,the microstructure of the alloy can be significantly improved,and the second phase?-Mg₁₇Al₁₂2 becomes a diffuse distribution from the coarse dendrite network structure.The granular shape improves the mechanical strength.With the increase of Al-Ti-B and Al-Ti-C contents,the refinement effect increases first and then decreases.When the addition amount of Al-Ti-B is 1.5wt.%,the refining effect is the best,the tensile strength is the highest,it can reach 225MPa,the tensile strength is 34%higher than that of the base alloy;when the Al-Ti-C is added in At 3wt.%,the finest effect is best,and the tensile strength is the highest,which can reach 235 MPa,which is 40%higher than that of the base alloy.The T6 treatment of the two best performance alloys has improved the mechanical properties.Compared with the non-refining agent,the tensile strength of AZ52X+1.5Al-Ti-B reaches 252MPa,which is 50%higher than that of the base alloy.The elongation rate reaches 10%;the tensile strength of AZ52X+3Al-Ti-C reaches 267MPa,which is 59%higher than that of the base alloy;the elongation rate reaches 10%;it reaches the performance level of ZL101 and can be powered by drones.Used on the housing,it has a wide range of application prospects.