Laser Assisted Brazing of Inconel 718: The Effects of Process Parameters and Subsequent Optimization

In the present study, laser brazing of Inconel 718 alloy with silver based filler metal using a Nd:YAG laser is investigated. The effect of process parameters including laser power, speed and pulse width on brazing geometry (wetting angle, spreading and depth of flow) are studied using response surface methodology (RSM). Then the multi-response optimization was employed to optimize the brazing process. The optimum brazing parameters are identified in order to improve the productivity and decreasing the total operating cost. The results indicate that laser power has a direct effect on spreading and a reverse effect on wetting angle, however the effect of speed is opposite of the laser power effect. Also interaction effect of speed and laser power is significant. Decreasing pulse width results in decreasing of wetting angle and increasing of the spreading. The experimental values obtained from optimization show that the developed models are accurate with less than 6% errors.