WCCo cutting tool inserts with diamond coatings

Abstract

Abstract WCCo cutting tool inserts were coated with diamond films using microwave plasma assisted chemical vapor deposition. Several pretreatment processes and combinations were used to enhance the diamond nucleation and growth: mechanical treatments with diamond powder seeding, acid etching of the cobalt using an electrolytic acid bath, and formation of a TiC or DLC interlayer using metal plasma immersion ion implantation and deposition (MePIIID). Scanning electron microscopy (SEM) was used to view the diamond film morphology, and microanalysis was used to examine for cobalt removal after acid etching. The diamond quality was characterized by Raman spectroscopy, and the adhesion between the film and the cutting tool inserts was estimated by indentation tests. The present work compares the different treatments of the WCCo insert surface, with particular reference to the adhesion between the diamond film and the cutting tool insert.