Laser Shock Peening to Strengthen Structural Components

Fleet Readiness Center East (FRCE) at Cherry Point, NC, is bringing on line a facility that will enable the centre to enhance the strength of structural components for Marine Corps F-35B LIGHTNING IIs from next year. The facility will then be one of only two such sites in the world to be able to provide a laser shock peening capability.

The state-of-the-art facility will allow FRCE to perform heavy structural modifications to the aircraft without the necessity for significant disassembly. Strengthening structures without adding metal or weight, thereby increasing aircraft life and reducing costs, laser shock peening has been used on the F-22 RAPTOR and in manufacture of aircraft and engine components, such as turbine blades.

Shot peening has been in use for decades – a process analogous to sand blasting, in which solid ablative particles hit the surface of an item, creating a relatively uneven surface. Laser shock peening overcomes that limitation by using a high-energy laser beam to create a shock wave in the target material, that results in compressive residual stresses that help improve damage tolerance, fatigue life and strength. The creation of a square beam, with consistent intensity throughout, is a major contributory factor to ensuring uniform treatment – which in turn contributes to resistance to fatigue stressing or cracking later in the component’s life.

The first two aircraft are due to undergo a validation/verification exercise at FRCE next summer and will be followed by enough aircraft to fill the facility for the next four to five years, observers close to the programme stated. FRCE will focus solely on the F-35B, while Ogden AFB, UT, will provide similar services for the F-35C and any overflow from FRCE.