Correlation between static indentation and micro cutting marble-based material

Abstract

Defining how the chip is formed during micro-cutting can be extremely difficult. The reason is the miniaturization of the process itself in relation to the macro cutting, as well as, the smaller depth of cut in relation to the tool tip radius. Besides, the micro-cutting mechanism is influenced also by the material being machined, as well as the processing conditions. Considering that marble is brittle by its nature, the micro-cutting mechanism does not match that defined for various types of steel, aluminum, etc. Experimental analysis revealed that during the micro-cutting of marble, two different processing modes occur. In the first (ductile mode) micro-cutting is based only on the elastic and plastic deformations. In the second, which corresponds to the brittle fracturing mode, the chip is created by the formation and uncontrolled growth of the cracks within the material. The critical depth of cut that separates the two modes can be determined in many ways, and one of them is the static indentation. In addition, this method can also be used to identify the types of cracks that occur during micro-cutting in a brittle fracturing mode, which is done in this paper.