Abstract
Laser cutting is associated with thermal effects at the cutting surface resulting in alteration of microstructure and mechanical properties. An abrupt change on the cutting surface is caused by a structural modified zone called heat affected zone (HAZ) due to weld heat treatment introduced by a high thermal gradient in the substrate material. Heat affected zone is often associated with undesirable effects such as surface cracking, fatigue resistance, etc. Therefore, it is important to minimize the thickness of this zone (HAZ). The objective of this work is to study the effect of high-power CO2 laser cutting on the heat affected zone. The laser cutting of low carbon steel (S235) is investigated with the aim of evaluating the effect of the input laser cutting parameters: laser power and cutting speed, on heat affected zone. An overall optimization was applied to find out the optimal cutting parameters that would minimize the thickness of heat affected zone. It was found that laser cutting parameters have an effect on the heat affected zone. The HAZ can be minimized by increasing the laser cutting speed and decreasing the laser power.