Physical and mechanical behaviour of mild steel under a CO2 laser

Abstract

In this paper, we investigate the physical and mechanical behavior of mild steel when machined using a CO2 laser. First, some of the etched mild steel specimens are spray painted and dried. A continuous wave (cw) CO2 laser beam with an estimated power of 35 Watts is then focused on both the painted and unpainted specimens for a wide range of exposure times. The machinability of the painted and unpainted specimens is observed. Both sets of specimens are then checked for any microstructural changes. It was clear that the unpainted specimens had no visible marks or microstructural changes even after the longest exposure of 1000 seconds. However, it was observed that exposure of the material to the beam had effects on the microstructure of the painted specimens even with as little exposure time as 30 seconds.