Analytical modeling of ductile-regime machining of tungsten carbide by endmilling

Abstract

Tungsten carbide is considered as difficult-to-machine material because of its super hardness and high brittleness. It has the tendency to undergo brittle fracture during machining with conventional technique. To achieve high-quality surface finish, tungsten carbide must be machined in ductile mode. This paper presents the theoretical and experimental research results of ductile-mode machining of tungsten carbide by milling process. An analytical model has been developed based on Griffith's energy-balance criterion for brittle fracture to predict the critical chip thickness for ductile-brittle transition in micro-cutting of tungsten carbide by endmilling. The experimental results have validated the theoretical model. It was established that ductile-mode machining of tungsten carbide can be performed efficiently by endmilling process within certain critical limits of cutting conditions governed mainly by the material properties and tool geometry. © 2010 Springer-Verlag London Limited.