MODELLING THE BASIC CUTTING ACTION AND MACHINING PERFORMANCE OF SINTERED METALLIC MATERIALS

Abstract

Extensive ‘classical’ orthogonal cutting tests have been run to study and model the basic cutting action and machining performance of a popular sintered metallic material widely used in structural automotive components. These tests were also run to assess whether the ‘Unified-Generalised Mechanics of Cutting Approach’ to force and power prediction in practical machining operations such as turning and drilling is likely to be applicable to sintered materials. The orthogonal cutting tests have shown that the modified mechanics of cutting analysis, incorporating the edge force, was equally applicable to sintered metallic materials while comprehensive drilling and turning tests over a wide range of operation variables have shown good qualitative and quantitative correlation between predicted and measured forces and torques thus confirming the validity of the predictive force models for machining sintered materials. This investigation has provided further evidence of the generic nature of the predictive machining performance modelling approach developed at the University of Melbourne and its applicability to both conventionally produced and sintered metallic materials for structural components. It has also been shown that the chip formation, cutting characteristics and mechanics of cutting analyses for the sintered metallic material for structural components, with its relatively high density and low porosity, are qualitatively similar to those for conventionally produced metallic materials. Quantitatively, however, the basic cutting quantities for use in the predictive force models are different and have to be established for each tool-workpiece material combination irrespective of whether the metallic material is a conventionally produced material or a sintered P/M material.