Preparation and Application of Low Temperature Supersonic Spraying Al-Si Coating

In order to solve the problem of ZM5 magnesium alloy parts which are easy deformation in the repair, the Al-Si coating is prepared by low temperature supersonic spraying technology. Tensile test by cementation dual-sample, metallographic microscope and image analysis software, micro-hardness were taken to value the bonding strength, porosity and hardness of the coating, respectively. and through the scanning electron microscope (SEM) was carried out on the coating surface morphology analysis, The results show the bonding strength was 51.3 MPa, the porosity of the coating prepared was 0.1%, and the micro-hardness was 135.9 HV_0.1, They are better than the eligibility criteria. The micro-structure indicates that the prepared coating is uniform, compact, and the sample is not deformed, and can be used for repairing of the mounting hole of the accessory casing. The coating prepared by low temperature supersonic spraying technology has high bonding strength, low porosity, good micro-hardness, compact coating and is not easy to be deformed. It can be used for the re-manufacturing of ZM5 magnesium alloy parts. According to the prepared magnesium alloy parts repair process, the method is applied to ZM5 alloy parts repair. The results show that the deformation of magnesium alloy is beyond the regulation. By further analyzing and studying the deformation causes of the parts, the magnesium alloy parts were repaired again with measures such as optimizing spraying parameters, improving special tooling and strengthening aging treatment, and the deformation amount of ZM5 alloy parts after repair met the technical requirements. The coating prepared by low temperature supersonic spraying technology has the advantages of high bonding strength, low porosity, good micro-hardness, compact coating and low deformation resistance, which can be used for ZM5 magnesium alloy parts repair and effectively solve the problem of ZM5 magnesium alloy parts repair and deformation.