On the improvement of the performance of high speed steel turning tools by tin coatings

Abstract Reactive ion plating using an arc source has been used to produce a TiN layer, 5 μm thick, on high speed steel turning tools. A comparison between the cutting edge durabilities of uncoated and coated tools when oblique turning mild steel at different cutting speeds has been carried out. Dry cutting has been used to accelerate wear which in turn has been assessed on the tool flank at different cutting speeds and fixed tool angles, feed and depth of cut. Wear curves have been plotted and Taylor equations have been derived. The results have shown that the Taylor equation for uncoated tools is TV 7.28 = 9.8 × 10 12 and that of coated tools is TV 3.34 = 4.85 × 10 7 where T is the tool durability in minutes and V is the cutting speed in metres per minute. Thus the cutting edge durability of coated tools has been found to be 4.5–5 times as much as that of uncoated tools.