Plasma assisted laser surface alloying

The combination of plasma arc with a Nd:YAG laser during surface alloying produces a synergistic effect which significantly increases the depth of the melt pool beyond that expected by a summation of the individual depths. Incremental increases in laser power produce larger depth changes than incremental increases in torch amperage. Displacing the sources emphasizes the effect. This could be attributed to an increase in interaction time. The depth of the heat affected zone experiences a lesser effect, suggesting that the synergism produces more efficient energy transfer into the liquid, therefore reducing energy transfer into the solid or HAZ. This would be accomplished by changes in fluid flow distribution. (C) 2003 Laser Institute of America.