Effect of hot isostatic pressing on microstructure and properties of cooled hot dip aluminum coating in magnetic field.

The effect of hot isostatic pressing (HIP) on the microstructure and properties of hot dip aluminum coating cooled in a magnetic field was investigated in this study. In order to improve the microstructure and properties of magnetic dip aluminum coating, hot isostatic pressing technology was used for post-treatment. Initially, a traditional aluminum-impregnated coating was prepared on the surface of titanium alloy TA15, an alternating electromagnetic field was applied during the forming and solidification process of the coating. Finally, the coating was treated with hot isostatic pressing technology. Analyzed three different coatings of the microstructure and element distribution, and tested the microhardness of the coatings at various positions. The test results revealed that the TA15 titanium alloy hot-dip aluminum coatings obtained through the three different processes exhibited a gradient structure. Compared with the traditional hot-dipped aluminum air-cooled coating, when an appropriate intensity of alternating electromagnetic field was applied during the coating solidification process, the outer coating structure was enhanced, the number of holes was reduced, the microstructure density increased, and the number of cracks significantly decreased. The defects of the 800 °C hot isostatic magnetic cold and hot dip aluminum coating were repaired under high temperature and pressure, resulting in a uniform and fine microstructure. The comprehensive properties of the magnetic cold and hot dip aluminum coating on the surface of the titanium alloy were effectively enhanced through hot isostatic pressing.