Quantitative assessment of plastic deformation in cutting tools materials

A method for quantifying the plastic deformation of cutting tool materials that is experienced during machining of high value manufactured components is needed to increase process efficiency (by at least 25%) and reduce energy use and material wastage. Its more accurate quantification would achieve these improvements by enabling better material selection for machining of complex metallic materials such as hardened steels and Nickel alloys commonly used in the aerospace manufacturing industry. It would also help accelerate the development of new tool material grades.

Plastic deformation of tooling materials (WC-Co cemented carbide) causes failure of the machining tools by accelerating wear through flaking of the hard coatings applied and then erosion of the tool material itself. The mechanisms of this deformation are not understood in part because it is so difficult to quantify. External measurement of wear to the tool geometry during use gives some indication of what is happening but uncertainties in the measured wear volume are not understood and certainly have not been correlated with measurement of the plastically deformed microstructure below the surface.

Development of methods of quantifying plastic deformation in the microstructure and external tool wear in three dimensions under different machining conditions would help to identify the key characteristics of the material microstructure that resist wear and thus lead to better material selection and development of new material grades with improved microstructures.