ION-IMPLANTATION OF COBALT-TUNGSTEN CARBIDE TOOLS FOR MACHINING TITANIUM

Cobalt-base tungsten carbide cutting tools were implanted with Cl, F, Br, I, S, In, Ga and Sn to dose levels of 2 x 10(16) ions cm-2 to 5 x 10(17) ions cm-2. Both untreated and implanted tools were tested in tu rning against a log of Ti-6Al-4V alloy at a cutting speed of 300 f.p.m . Each test was carried out for 1 min and the uniform flank wear was m easured, whereupon the tool was tested for a further 1 min. Testing co ntinued in this fashion until the uniform flank wear approached or exc eeded 0.02''. The distribution of the implanted elements was determine d by secondary ion mass spectrometry. In general, doses of 1 x 10(17) ions cm-2 increased tool life by a factor of two in the case of the ch lorine and indium implants. Other implant elements were less effective in increasing tool life against the titanium alloy.