Surface crack of components repaired by laser

Surface crack of steel components was repaired with twin laser beams. The experimental results showed that the surface crack with the wideness of 0.2/spl sim/0.3 mm could be repaired under laser power of 3 kW. The repaired deepness is about 6.5 mm. There was an obvious joined band between filled region and substrate of component. The microstructures of repaired region were adnate cellular crystal, dendrite crystal.