A. Jutte, C. Cross, T. George, M. Shepard, Air Force Research Laboratory, Wright Patterson AFB, OH

Summary:

The use of Laser Shock Processing (LSP) for fatigue life enhancement in a directionally solidified (DS) turbine engine blade has been explored. LSP was applied to DS turbine engine blades and representative coupons for fatigue testing and residual stress analysis respectively. Residual stresses due to LSP were analyzed using a modified hole drilling technique both before and after a representative thermal soak. A unique test configuration was developed for the evaluation of the fatigue capability of the turbine blades at temperature. The fatigue lives, with and without LSP, were compared. Sufficient LSP induced residual stresses persisted after thermal exposure to positively impact fatigue life.