| Title | Why can TiAlCrSiYN-based adaptive coatings deliver exceptional performance under extreme frictional conditions? |
|---|---|
| Authors | Beake B.D. , Fox-Rabinovich G.S. , Losset Y. , Yamamoto K. , Agguire M.H. , Veldhuis S.C. , ENDRINO ARMENTEROS, JOSÉ LUIS, Kovalev A.I. |
| External publication | Si |
| Means | Faraday Discuss. |
| Scope | Article |
| Nature | Científica |
| JCR Quartile | 1 |
| SJR Quartile | 1 |
| JCR Impact | 3.821 |
| SJR Impact | 1.751 |
| Web | https://www.scopus.com/inward/record.uri?eid=2-s2.0-84863701212&doi=10.1039%2fc2fd00131d&partnerID=40&md5=cf4b84b8a9ee7ba1787e34270fd1d7f6 |
| Publication date | 01/01/2012 |
| ISI | 000305892200018 |
| Scopus Id | 2-s2.0-84863701212 |
| DOI | 10.1039/c2fd00131d |
| Abstract | Adaptive TiAlCrSiYN-based coatings show promise under the extreme tribological conditions of dry ultra-high-speed (500-700 m min -1) machining of hardened tool steels. During high speed machining, protective sapphire and mullite-like tribo-films form on the surface of TiAlCrSiYN-based coatings resulting in beneficial heat-redistribution in the cutting zone. XRD and HRTEM data show that the tribo-films act as a thermal barrier creating a strong thermal gradient. The data are consistent with the temperature decreasing from ~1100-1200 °C at the outer surface to ~600 °C at the tribo-film/coating interface. The mechanical properties of the multilayer TiAlCrSiYN/TiAlCrN coating were measured by high temperature nanoindentation. It retains relatively high hardness (21 GPa) at 600 °C. The nanomechanical properties of the underlying coating layer provide a stable low wear environment for the tribo-films to form and regenerate so it can sustain high temperatures under operation (600 °C). This combination of characteristics explains the high wear resistance of the multilayer TiAlCrSiYN/TiAlCrN coating under extreme operating conditions. TiAlCrSiYN and TiAlCrN monolayer coatings have a less effective combination of adaptability and mechanical characteristics and therefore lower tool life. The microstructural reasons for different optimum hardness and plasticity between monolayer and multilayer coatings are discussed. © The Royal Society of Chemistry 2012. |
| Universidad Loyola members |