Definition - What does Peening mean?
Peening is a surface modification process used to improve a material by the application of a mechanical force. It is used to strengthen a metal surface, thereby making it more resistant to external degradation and corrosion factors.
Corrosionpedia explains Peening
There are two main types of peening: hammering and blasting. Both are cold-working processes that involve the deformation of a metal surface.
Hammering is the expansion of a cold metal surface by applying blunt forces and inducing compressive and tensile stresses.
Blasting is primarily of two types - shot and laser. Shot peening involves the propulsion of cast iron particles under high pressure onto the metal surface to be treated. Laser peening involves the use of high-energy beams to generate shock waves on the metal surface.
All types of peening propagate the metal's resistance to the formation of cracks, fatigue, cavitation and stress corrosion.