Effect of different static load conditions on the comprehensive service performance of LPBF-IN718 nickel-based superalloy treated by ultrasonic surface rolling

The laser powder bed fusion-fabricated IN718 nickel-based superalloy was treated using the Ultrasonic Surface Rolling Process (USRP) to enhance its comprehensive service performance. Four parameter sets with different static loads were designed to investigate the effects of USRP on LPBF-IN718. This study primarily employed XRD, EBSD, electrochemical corrosion tests, and friction and wear tests to characterize the microstructure, corrosion resistance, and friction and wear properties of the samples before and after USRP treatment. The results indicate that the overall service performance of LPBF-IN718 is significantly improved after USRP treatment. The surface roughness decreased by 77.86%, and the microhardness increased by 30.4%. Under a static load of 1300 N, the USRP-treated specimen exhibited the best corrosion resistance, with a 51.39% reduction in the corrosion current density. Additionally, the specimen exhibited the best friction and wear performance, with the average friction coefficient reduced by approximately 47%. USRP treatment significantly enhances the corrosion resistance and friction and wear performance of LPBF-IN718.