Effect of Nd-YAG Laser Pulses on Mechanical Properties of Carbontriding Steel type (AISI 1006)

Nd: YAG laser was applied to modify the surface characteristics of carbonitriding steel, such as microstructure, surface roughness, micro hardness and wear resistance. In this work; traditionally surface heat treatments carbonitriding was done on low carbon steel type AISI (1006 ) by using mixture from 40% NaCN ,30% Na2CO3 and 30% NACL ,followed applied Nd: YAG laser surface treatment. The laser parameters were energy 0.89, 2, 4 and 9 J, pulses duration 1, 2.33, 4.47and 9.87 ms, spot diameter 0.1049,0.1065,0.1077 and 0.1092 mm, with fix wavelength 1604nm. The laser surface treatment cycles wasmelting the layer surface, holding and rapid cooling in air medium. Optical microscopy (OM) and scanning electron microscope (SEM) has been used to study the microstructures and cross-sectional of molted and heat affected zones respectively. The wear test was done by using pin -on-disk principles were satisfied to measure the wear rate. The result shown that increasing in laser energy effects to increase in the area of melted and heat affected zones of nitriding steel. Also increase in laser Pulses duration lead to increases in micro hardness increased which increased about 81% while wear rate decreased 69%.