Investigation on the material surface strengthened by YAG laser guiding combined-pulse discharge

The method of the laser guiding combined-pulse discharge was studied to increase the phase-change layer depth of the laser guiding discharge pit, and avoid the energy loss induced by serious material surface vaporization. This method includes two schemes. One is increasing laser pulse numbers in the process of discharge to enhance the ability of the laser guiding. The other is increasing discharge pulses,in which the input of discharge energy is controlled by the temperature of the machining point so that the energy concentration is reduced and the depth of the strengthening pit is increased. The results showed that the diameter of the discharge pit reduced from 690μm to 652μm and 653μm, and the depth increased from 85μm to 100μm and 92μm, if increasing laser pulse numbers in the late discharge pulse and combining laser and discharge pulses respectively.These methods are applicable for the surface strengthening process of mechanical components.