Abstract
This study investigated the stress relaxation and fatigue life and strength of laser peened single crystal nickel superalloy specimens following hot corrosion exposure and then fatigue testing compared to un-peened and shot peened specimens. The specimens were treated by conventional laser peening and a new cyclic laser peening plus thermal microstructure engineering process. Stress measurements by slitting showed the plastic penetration depth of laser peening exceeded shot peening by a factor of 24. Un-peened and peened specimens were exposed to sulphate corrosives at 700°C for 300 hours and then fatigue tested. Tests of five non-laser peened specimens all failed in low cycle fatigue regime whereas three identically tested laser peened specimens all achieved multi-million-cycle runout without failure, indicating fully consistent large benefit for life by laser peening. Additional tests showed fatigue strength improvement of 2:1 by laser peening.
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
