Cutting forces evolution with tool wear in sintered hardmetal turning with CVD diamond

Abstract

The cutting forces evolution is investigated during the dry turning of sintered hardmetal (WC-25 wt.%Co) with chemical vapour deposition (CVD) diamond brazed tools. The effect of the cutting speed ( v), feed ( f) and depth of cut ( d) in the cutting forces is analysed, being found a clear relationship between tool forces, tool wear and workpiece surface finishing. The chosen test conditions ( v=40 m min −1, f=0.03 mm rev. −1 and d=0.1 mm) allow to set up a threshold main cutting force value of 35 N below which excellent workpiece finishing is assured with low cutting tool damage. Flank tool wear, besides cratering on the rake tool face and hardmetal deposition on the tool surface, are the main damage modes of the cutting tools.