US EPA

1756127 

Journal Article 

The development of high-performance CVD diamond coated cutting tool inserts 

Olson, JM; Windischmann, H 

1998 

8 

2 

105-124 

WOS:000076621600004 

The use of diamond as a thin film or a coating enables us to
exploit the wear resistance properties of the thin film while taking advantage of the bulk
mechanical properties (toughness) of the underlying substrate base material. However, in order to
achieve this goal in practice, it is important to optimize both the physical properties of the
diamond film and the properties of the film/substrate interface. Early efforts to produce
diamond-coated WC Co products did not improve the adhesion strength to a level that provides a
diamond-coated material of sufficient utility to the end user. In this paper we describe the
essential characteristics of the diamond/substrate interface which, when acting together, have
recently led to significant improvements in the adhesion strength of the diamond film to the
underlying substrate. These characteristics fall into three general categories: a) chemical
composition, b) phase composition, and c) microstructural composition. All of these
characteristics are produced using essentially one process step that was developed to produce
these characteristics in such a way that other important physical features are not compromised.
Finally, we will review the results of efforts to optimize the physical characteristics of the
diamond deposits for metal cutting applications as well as overview results of worldwide testing
of these diamond-coated WC-Co based cutting tool inserts. 

diamond; cutting tools; adhesion; fracture propagation; nucleation density; C-Co; wear resistance; SEM; EDS