On the Machinability of Medium Density Fiberboard by Drilling

Abstract

Machinability is one of the most important technological properties in the machining process. The machinability index is a numerical value that shows the degree of difficulty or ease with which a material can be machined. The research described herein consisted of drilling blind holes in a medium density fibreboard (MDF) using a cemented carbide tool. Different cutting speeds (vc) and feeds (fn) were used in the tests. The goal was to determine the value of the axial force (Ff), the cutting torque (Mc), and the chip thickness. To analyse signals involving axial force and cutting torque, a methodology for determining the average values of these signals was proposed to avoid random changes in signal values. The results obtained were used to determine the MDF machinability index in the drilling process based on the measurement of the axial force, cutting moment, and shear angle of the chips. The results obtained showed that the machinability index based on the adopted criteria is constant for a given workpiece and does not depend on the cutting parameters.