| Description |
Metal fatigue is microscopic damage/deformation that occurs each time a component is loaded. Metal fatigue is very common in aircraft structures, as they are often made as thin as possible for weight considerations. In order to continue flying older aircraft, cold expansion, or cold-working, was developed in the 1960's to improve the fatigue lives of fastener holes. Testing has shown that cold-working techniques improves the fatigue life of new fastener holes, but little work has been done to analyze the effects of cold-working a hole that already contains fatigue damage. This research will analyze and quantify cold-working effects for previously damaged fastener holes. |
