Preloaded laser shock peening

A method of laser shock peening a gas turbine engine article by loading the article such that a portion of the article to be laser shock peened is placed in a loaded condition while the portion is laser shock peened using a laser to fire a laser beam with sufficient power to vaporize material on a laser shock peening surface of the portion of the article to form a region in the portion having deep compressive residual stresses imparted by the laser shock peening process extending into the article from the laser shock peened surface. The loaded condition may be either in compression or preferably tension. The loaded article is continuously moved while continuously firing a stationary laser beam, which repeatably pulses between relatively constant periods, on a portion of the article with sufficient power to vaporize material on the surface of the portion of the article with the pulses around laser beam spots formed by the laser beam on the surface and form a region having deep compressive residual stresses extending into the article from the laser shock peened surface. Flowing a curtain of water over the surface upon which the laser beam is firing while moving the article until the laser shock peened surface is completely covered by laser beam spots at least once. The surface may coated with paint or tape which is the material used to produce the plasma or the surface may be unpainted and the metal of the article is used to produce the plasma.