Laser produced plasma affects on welding

Acoustic data and high speed pictures indicate that a (laser-supported combustion wave (lscw) is generated and propagates away from the surface in the direction toward the laser. The high speed pictures also show that numerous plasmas are generated during one laser pulse. The optical data show that the number of plasmas generated and their initiation times depend upon laser power. The depth of penetration is also dependent upon the number of plasmas generated, with more plasmas producing more penetration. This latter fact supports the conclusion that the plasma improves the efficiency of the laser process. Thus, a plasma in the form of a laser supported combustion wave is generated and acts to convert the poorly absorbed laser radiation into blackbody radiaiation. The blackbody radiation has a broadband short wavelength spectrum which is readily absorbed by most materials.