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 DISCUSSIONS |
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 |
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