Interface characteristics of CVD diamond coating on WC-Co cemented carbide substrate

Abstract

Chemical vapor deposition (CVD) diamond coatings on WC-Co substrates have gained significant attention due to their exceptional mechanical properties and wide-ranging applications in cutting tools, wear-resistant parts, and other advanced technologies. The interface bonding between CVD diamond coatings and WC-Co substrates plays a crucial role in determining the performance and durability of the coated tools. In this paper, the characteristics of the interface microstructures between the CVD diamond coating and WC-Co substrate was investigated by high resolution transmission electron microscopy (HRTEM) and EDS. The structures were observed in the system where the diamond coating (film) was deposited on the WC-Co cemented carbide substrate using HF-CVD technology. The results indicate three types of structures at the diamond coating-substrate interface: WC/diamond, WC/graphite/diamond, and Co/graphite/amorphous carbon/diamond. The bonding mechanisms at the CVD diamond coating/WC-Co substrate interface are discussed.