Metal-boron-carbon Based Coatings-novel Material with High Hardness and Fracture Resistance
| Authors | |
|---|---|
| Year of publication | 2018 |
| Type | Conference abstract |
| MU Faculty or unit | |
| Citation | |
| Description | Nowadays used hard protective coatings are often based on ceramics. They generally exhibit high hardness and high stiffness, however, these positive features are often accompanied by negative brittle deformation behaviour. If a crack is formed, it can easily and rapidly spread which can lead to a sudden premature failure of the coating as well as the whole coated tool. The current trend in surface engineering is to sacrifice some of the hardness in favour of enhanced ductility and fracture toughness. According to the ab-initio models, boron and carbon-based nanolaminates such as Mo2BC should exhibit an unusual combination of high stiffness and moderate ductility. Nanolaminates with tantalum, tungsten and molybdenum were predicted to exhibit the best mechanical properties making them the best candidates for experimental synthesis. These materials (Mo-B-C, W-B-C and Ta-BC) were sputter deposited at moderate temperatures employing DCMS or HiPIMS. The coatings are prepared in a fully amorphous form, as nanocomposite system and also in a fully crystalline form. The hardness of these coatings was higher than 20 GPa and the fracture resistance of the coatings is shown to be significantly enhanced compared to the state-of-the-art protective coatings such as TiN or TiAlN. |
| Related projects: |