Research on Laser Hardened Bead Geometry in Laser Hardening Parameters of ASTM Grade3 Pure Titanium

Abstract

Abstract
In the presented study, the laser transformation hardening of commercially pure titanium sheet material of thickness being 1.6 mm is investigated using CW (continuous wave) 1.6 kW solid state Nd:YAG laser. Commercially pure titanium has widespread application in various fields of industries including the medical, nuclear, automobile and aerospace. A full factorial design (FFD) with response surface methodology (RSM) is employed to establish, optimize and to investigate the relationships of three laser transformation hardening process parameters such as laser power, scanning speed, and focused position on laser hardened bead profile parameters such as hardened bead width, hardened depth, heat input. RSM is used to develop pseudo-closed-form models from the computational parametric studies. Effects of laser process parameters: laser power, scanning speed and focal point position on laser hardened bead geometries such as hardened bead width, hardened depth and heat input were carried out using RSM. Results indicate that the scanning speed and laser power have the significant effect as compared to the focal point position on the laser hardening process parameters. The scanning speed has a positive effect on all responses while the laser power has a positive effect particularly on hardened bead width and as compared to hardened depth and heat input. The optimum laser hardening conditions are identified sequentially to minimise hardened depth, heat input, and maximum hardened bead width. The validation results demonstrate that the developed models are accurate with low percentages of error (less than 7.409%).
Keywords: Laser transformation hardening; response surface methodology; full factorial design; analysis of variance; bead geometry

Cite this Article
Duradundi Sawant Badkar. Research on Laser Hardened Bead Geometry in Laser Hardening Parameters of ASTM Grade3 Pure Titanium. Research & Reviews: Journal of Physics. 2017; 6(1): 22–37p.