Prediction of surface roughness parameters in drilling of MDF composite panel using Box-Behnken experimental design (BBD)

Medium Density fiberboards are appropriate for many interior and exterior industrial applications. The degree of surface roughness of the MDF board plays an important role, since any surface irregularities reducing the final quality of the product. Design of experiments has been used to study the effects of the drilling parameters such as speed, feedrate, and drill diameter (input data´s) used on the prediction of surface roughness (output response) on drilling MDF composite. A mathematical model on the surface roughness has been developed in terms of the input parameters. The effect of these parameters on surface roughness has been investigated using Box-Behenken experimental design. Response contours were constructed for determining the optimum drilling condition for a required surface roughness. The developed model establishes a correlation between speed, feed rate and drill diameter that influence the surface roughness in a MDF panel. Analysis of variance (ANOVA) is employed to study the surface roughness characteristics in drilling operation of MDF board. The analysis of variance showed high coefficient of determination (R²) value of 0.995, thus ensuring a satisfactory adjustment of the second order regression model with experimental data. The verification experiment carried out to check the validity of the developed model predicted surface roughness with in 4.6%error.