• residual
• peening
• laser shock peening
• laser
• fatigue
• compressive
• 7050
• shock
• stress

In aeronautical constructions, fatigue is an issue of great concern.

Laser Shock Peening is an innovative technology which promises considerable improvements to the development of a residual stress field capable of mitigative fatigue induced failures. The process has been successfully used in military applications for compressor and fan blades and for primary structures and is being introduced in the commercial aviation.

The physical principles of the Laser Shock Peening, such as the Plasma Generation and the Shock Waves propagation, are reviewed and the cost/benefits of the technology are discussed. In order to investigate the influence of Laser Shock Peening on fatigue life of thick components, a test campaign was carried out by the author within EADS - Innovation Works Deutschland; the test campaign brought out that the Laser Shock Peening is capable of sensitive fatigue strength enhancements.

Some unexpected failures occurred during the experimental activities. In order to investigate this unforeseen behavior, numerical simulations by means of the finite element method were carried out by the author at the Department of Aerospace Engineering of University of Pisa regarding the specimens involved in the test campaign. The simulations highlighted a modification of the stress field in Laser Shock Peened specimens which explains the unexpected failures.