Abstract
A new ΔK-decreasing test method was developed by using metal film. The film was adhered to a through elliptical hole in a base plate and was fatigued in accordance with the displacement constraint along the hole circumference in the base plate subjected to a cyclic stress. Commonly, a stress intensity factor range was increased with a crack propagation under a constant stress amplitude but was decreased toward the hole edge because of the difference in thickness between the film and the base plate in this ΔK-decreasing test method. As a result, the fatigue crack propagation rate was decreased and was arrested near the hole edge under the constant stress amplitude to the base plate. The threshold stress intensity factor ranges were obtained for some kinds of metal films.
