Wear of CrC-coated carbide tools in dry machining

Abstract

This paper discusses the tribological characteristics and cutting performance of chromium carbide (Cr x% C)-coated carbide tool inserts and micron-drills in dry machining. Cr x% C coatings have been deposited with different optical emission monitoring (OEM) set values, x%, of chromium target “poisoning” by unbalanced magnetron sputtering and OEM control. The microstructures and mechanical properties of Cr x% C coatings have been measured by the experiments of scanning electron microscope (SEM), nanoindentation and adhesion. Experimental results indicate that the coating microstructure, mechanical properties and wear resistance vary according to OEM set values. Cr 10%C-coated inserts showed the best wear resistance in AISI 1045 steel turning test. Cr 50%C-coated tools have performed exceptionally well in both copper turning and printed circuit board (PCB) through-hole drilling tests. The service life of Cr 50%C-coated tool is four times higher than that of an uncoated tool in the PCB through-hole drilling test.