Sensitivity analysis on surface topography for laser-surface-texturing of Hastelloy C-276 superalloy: studies on micro-structure morphology characterization

In the present scenario, controlling surface characteristics of superalloys such as friction, wear rates, and fatigue failure needs special attention for various manufacturing applications. The present research work deals with the analyses of a fiber laser surface texturing of Hastelloy C-276 to utilize the generated surfaces for high power applications. Texturing on Hastelloy C-276 surface has been achieved with the overlapping of linear micro-grooves. The effects of laser process parameters like laser power, scan speed, pulse frequency, and duty cycle on the surface morphology like arithmetic mean surface roughness (Ra), skewness (Rsk), and kurtosis (Rku) have been studied. Empirical modeling of the process parameters for fiber laser surface texturing of Hastelloy C-276 has been carried out by response surface methodology. A sensitivity analysis is conducted here to find out the sensitivity of process variables on surface characteristics. The combination of laser power of 19.93 W, pulse frequency of 60 kHz, a duty cycle of 38.96%, and a scan speed of 8.41 mm/s lead to the optimized roughness criteria are 1.2 mu m, - 0.35, and 3 for Ra, Rsk, and Rku respectively.