Diamond coatings designed for machining CFRP, ceramics, graphite, and aluminium alloys

Mapal has developed extremely hard and wear-resistant diamond coatings for machining materials such as CFRP, ceramics, graphite and aluminium alloys.

The tool manufacturer has coating technologies to coat indexable inserts and solid carbide tools using PVD or CVD processes. The choice of process depends on the relevant application parameters. For dry machining and high cutting speeds, CVD is usually chosen; in the case of unstable machining situations or difficult machining conditions, the tougher PVD coatings are applied.

Diamond-like carbon coatings (DLC) are deposited using PVD or a plasma-enhanced CVD process. These coatings are formed by a mixture of sp2 hybridised carbon atom bonds (graphite) and those with sp3 hybridisation (diamond). The mixing ratio determines the physical and mechanical properties of the coatings. The more sp3 atomic bonds there are, the harder the coating.

Since the coating process functions via a chemical reaction combined with mechanical clamping, defined etching of the carbide surface and seeding are important during pre-treatment.

Whether fine-grained microcrystalline or nanocrystalline layers are produced during coating is determined by the temperature, pressure, and flow of the respective reactive gases during the process. Theoretically, layers up to a thickness of 50 µm can be produced by HF-CVD. The company currently focuses on the range between 3 µm and 15 µm, depending on the respective application.

Mapal | mapal.com