Method and device for laser peening correction size precision online control for welded metal plate

The invention provides a method and device for laser peening correction size precision online control for a welded metal plate. A laser machine emits a laser beam, the laser beam is transmitted to a workpiece welding area through a light path system, a water limiting layer covers the welding area, and a limiting layer is formed. Under the action of laser pulse, impulse waves are formed on the welding surface, residual compressive stress is generated in the welded metal plate, and the residual compressive stress is eliminated. Efficiency of laser penning is high, a deep residual compressive stress layer can be generated, size correcting efficiency is high, the size correcting makes the surface and a certain depth range of a peening area of a welded piece to be subjected to plastic deformation, the straightening purpose is achieved, and meanwhile, fatigue strength of a welded joint is improved. According to the method and device for the laser peening correction size precision online control for the welded metal plate, precise size correcting can be conducted on the welded piece, working efficiency is high, controllability is good, and the range of application is wide.