This study investigates the effects of cutting speed and assisted gas pressure on the cutting-edge quality in laser machining of High-Speed Steel (HSS) and Mild Steel (MS) using oxygen as the assisting gas. The kerf width ratio (KWR) studied at the entry, middle, and exit points and the heat-affected zone (HAZ) was observed. Taguchi L9 orthogonal array was employed to optimize the experimental design, minimizing trials to achieve parameter impacts. Measurements of KWR and microscopic analysis of the HAZ were conducted to assess laser machined surface quality. Results reveal that cutting speed significantly affects KWR, with higher speeds producing narrower kerfs due to improved heat dissipation. HAZ analysis highlights distinct thermal effects, such as recast layers and gradients, with variations between HSS and MS attributed to differences in thermal conductivity and material properties. These findings provide valuable insights into optimizing laser machining parameters to enhance accuracy and efficiency, offering recommendations for various industrial applications.
