seen in fig3 the 50 overlapping pattern can be observed this overlapping pattern substantially reduces the likelihood of igscc occurring with respect to fig4 this illustrates a close up of the surface treatment of the destructively ground welded zone again as with fig3 the surface treatment through the use of the pulse laser substantially prevents the creation of igscc independent of the as machined or ground surfaces the igscc mitigation method works because carbon and chromium can go back into solid solution in the alloy matrix material adjacent to the grain boundaries along with the fact that the surface treatment using the pulse laser can be performed to reasonable depths at reasonable speeds the use of a pulse laser for surface mitigating has several advantages when compared to a continuous laser first since pulsed laser heats the material impulsively the time at the temperature of the heated zone is much less than that for a continuous laser this is true because with a continuous laser a steady temperature pattern must be established around a relatively slowly moving heat source second since the peak energy or power density is much higher for a pulse laser than that of a continuous laser surface breakdown and associated high efficiency energy absorption are initiated much faster by a pulsed laser therefore net power of a pulsed laser is less than that for a continuous laser doing the same job third the wavelengths of neodymium lasers glass or yag yttrium aluminum garnet are such that no special surface treatment is necessary prior to its use in surface desensitization this is not the case for a continuous wave co 2 laser.