ANALYSIS OF MACHINING PARAMETERS INFLUENCING SURFACE FINISH OF MEDIUM CARBON STEEL DURING LATHE TURNING

The Effect of Machining Parameters on Surface Roughness of Medium Carbon Steel of 0.3%C during Turning Operation on Lathe Machine using Full Factorial Design was investigated. The data used for the work was from an earlier research titled ‘’effect of machining parameters on the surface roughness of medium carbon steel using lathe machine’’. These data points were used to perform the analyses in full factorial design. In the factorial design analysis, the design type selected for this study was the full factorial design. As applicable with the response surface method, the same Design Expert (version 13.0.5.0) Minitab software package for design of experiments was used to analyse and generate model equation for surface roughness. The selected model for this design was the two factorial interaction (2FI). Based on this design, one hundred and twenty-five (125) data points, extracted from the five hundred (500) data points were used to perform the analysis. The result revealed that a mathematical model was developed for the prediction of surface roughness of 0.3%C steel during turning operation on the Lathe machine using full factorial design. It was observed that the predicted values of surface roughness were virtually the same with that of the actual values obtained from the experiment. ANOVA result of the model revealed that the “Model F-value” of 9300.94 implies the model was significant. Predicted R² of 0.9996 was in reasonable agreement with the Adjusted R² of 0.9998; i.e. the difference was less than 0.2. Adeq. Precision measures the signal to noise ratio. A ratio greater than 4 is desirable. Therefore, the ratio of 442.465 indicated an adequate signal implying that the model can be used to navigate the design space. The result also showed that interaction between cutting speed and feed rate was a slow steady increase as values of cutting parameters were being increased from 0.15rev/min to 0.21rev/min. Finally, the result from full factorial design was supported by the result from ANN, that feed rate has the highest influence or effect on surface roughness of 0.3%C steel during turning operation on the lathe machine. Full factorial design therefore can be used for determining the effect of machining parameters on 0.3%C steel during turning operations on lathe machine