Effects of ultrasonic surface rolling process on the microstructure and wear resistance of 2195 Al-Li alloy processed by laser powder bed fusion

•Ultrasonic surface rolling has most significant deformation strengthening effect.•The wear severity in laser powder bed fusion of 2195 Al-Li alloys is mitigated.•Multiple strengthening mechanisms enhance the material’s wear resistance. This study presents a comparative analysis of the impacts of surface rolling (SR) and ultrasonic surface rolling (USR) techniques on the microstructure and wear resistance of 2195 Al-Li alloy processed by laser powder bed fusion (LPBF). The results show that both SR and USR processes induced grain refinement, increased dislocation density, and converted tensile residual stress into compressive residual stress in the surface layer of the original samples. Compared to the SR process, the USR process exhibited more pronounced strengthening effects due to its unique acoustic effect and dynamic recrystallization mechanism. With the application of USR, the average coefficient of friction for the sample reduced from 0.41 to 0.32. This enhancement in wear resistance can be attributed to the synergistic effects of grain boundary strengthening, dislocation strengthening, and stress strengthening mechanisms.