Abstract
In the present work, a new surface mechanical strengthening (SMS) technique named stress ultrasonic rolling (SUR), which is ultrasonic rolling (UR) assisted with a uniaxial tensile elastic stress field, was reported and successfully conducted on 5 % wt TiB2/7050Al composite. Based on the experimental analysis and numerical simulation, the effects of SUR on surface integrity and fatigue performance of the composite were comprehensively investigated. Compared with ordinary UR, SUR further enhanced the fatigue strength at 106 cycles of the composite by 5 % and prolonged the fatigue life of the composite under the stress level of 532.8 MPa by 1.8 to 3.3 times, which are attributed to the comprehensive effect of excellent surface finish, larger and deeper compressive residual stress (RSc) layer, dispersed TiB2 particles distribution in the surface, and superficial nanocrystalline structures. Besides, the assistance of uniaxial tensile elastic stress field did not increase the amount of surface plastic deformation, which indicates the RSc generated by SUR should have similar mechanical and thermal stability to that produced by ordinary UR treatment.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
