Mechanical applications of thin and thick diamond films

Abstract

Abstract Several applications of thin and thick diamond films have been developed in our laboratory which enable us to exploit the well-known property of diamond, i.e. the highest hardness on earth. These applications include cutting inserts of either a coated (thin film) type or a brazed (thick film) type whose performance has been evaluated and compared with both conventional sintered and single-crystal diamond insert (tool) as well as tungsten carbide insert in cutting very-hard-to-turn materials such as a 18 wt.% Si aluminium alloy or a dispersion-strenthened aluminium alloy including 20 vol.% SiC whiskers. The performance test is extended to a precision turning operation of pure aluminium which requires a very good surface finish. Other applications of diamond film here have been found in antiabrasive tools; one is a dresser used for forming grinding wheels and another is a shearing tool for cutting very abrasive materials such as a polishing tape with a top SiC coating layer. Finally, the development of an indenter mounting a thick diamond film flake shaped into a scratch tester tip has been explained as one example of diamond films for use as various mechanical parts or elements.