Case Study in Shot Peening - Subsurface Residual Stress Nondestructively Quantified for Alloys

Author:  Shot Peening Staff
Source:  The Shot Peener magazine, Vol 18 / Issue 1, Winter 2004
Doc ID:  2004044
Year of Publication:  2004
Abstract:  
PIPA measures shot peening effects at the atomic level Advances have been made in the design of metallic / intermetallic alloys and in the surface treatments which increase performance and decrease component weight. One such surface treatment is shot peening, which is used to improve durability and limit crack initiation in high performance / high stress components, such as turbine blades and engine parts in aircraft. However, material evaluation technologies have been limited in their ability to characterize the effect of these surface treatments on a component's structural integrity. Shot peening induces subsurface compressive stress that increases a component's resistance to cracking. It remains unclear how this compressive stress interacts with thermal and mechanical fatigue over time. Consequently, little credit can be taken for shot peening in design and maintenance activities.