Experimental investigation of plasma arc cutting process to evaluate the characteristics of kerf geometry using ANOVA

The effects of cutting speed and current on plasma cut quality were investigated. Regression modeling was used to establish relationship between process parameters and responses. Analysis of variance was performed to determine the significance of independent variables influencing the kerf geometry. The analysis showed that the proposed regression model fits the experimental data fairly well and the selected variables influence kerf length difference and top kerf width substantially. However, while the bottom kerf width was significantly influenced by cutting speed, it was not affected by the current. The analysis results were compared with the experimental data and were found to be in good agreement. The images captured with high-speed camera using appropriate band-pass filter revealed that the plasma flows under the workpiece were affected by the process parameters. The tail length and the direction angle of the plasma flow dictated the shape of the kerf geometry.