Laser welding is a process method that uses a high-energy-density laser beam as the heat source to locally heat the materials to be welded to a molten or vaporized state. After condensation, a firm welded joint is formed. It is a non-contact and high-precision welding technology, widely used in manufacturing, electronics, aerospace, medical and other fields.

Laser beams are generated by lasers (such as fiber lasers, CO₂ lasers, disc lasers, etc.), focused into spots with diameters ranging from micrometers to millimeters by an optical system, and then projected onto the surface of the workpiece. After light energy is converted into heat energy, the local temperature of the material rapidly rises to the melting point or boiling point, forming a molten pool. As the laser beam moves, the molten pool cools and solidifies, forming a weld seam.