Laser Beam Micromarking on Inconel 625 Superalloy
A.P. Tiwary and I. Shivakoti
The present research investigates the laser beam micromarking process on Inconel 625 superalloy. Important laser beam micromarking process variables viz. current, pulse frequency and scanning speed were considered for experimentation on the basis of L9 orthogonal array of the Taguchi design of experiments (DOE). Material removal rate (MRR) and kerf width have been evaluated at different process parametric combination and the detailed parametric study has been presented. To attain the optimal process parametric combination, evaluation based on distance from average solution (EDAS) method has been successfully adopted. Mathematical equations have been established for each performance characteristic to connect the marking parameters and process output relationship. The analysis of variance (ANOVA) indicated that the laser beam micromarking process parameters have a great impact on performance characteristics. Current was found to be the most dominating factor among the three process variables for both MRR and kerf width followed by pulse frequency and scanning speed. The optimal process parametric combination for accomplishing higher MRR and lower kerf width during laser beam micromarking of Inconel 625 superalloy was established as current of 22 A, pulse frequency of 4600 Hz, and 7 mm/s scanning speed. The confirmation experiment at obtained optimal parametric setting validated the methodology and framework used in the present experimental investigation to enhance the overall laser micromarking process.
Keywords: Nd:YAG laser, Inconel 625 superalloy, laser beam micromarking, process parameters, evaluation based on distance from average solution (EDAS), analysis of variance (ANOVA), multi-objective optimization.