Ab initio-guided development of super-hard Mo-Al-Cr-N coatings

SCRIPTA MATERIALIA

卷:140

Article

Klimashin, F. F.¹  Mayrhofer, P. H.¹ 

[1] TU Wien, Inst Mat Sci & Technol, Getreidemarkt 9, A-1060 Vienna, Austria

关键词: Superhardness;    Mo-Al-Cr-N;    Reactive sputtering;    Nitrogen vacancies;    Mechanical properties;   

DOI  :  10.1016/j.scriptamat.2017.06.052

来源: Elsevier

【 摘 要 】

The ab initio-guided adjustment in N-2-partial pressure during reactive magnetron sputtering allowed the preparation of single-phase cubic-structured Mo1-x-yAlxCryNz coatings with Al-contents up to even x approximate to 0.6. Combining with low Cr-concentrations, Al-enrichment significantly enhances material strength. The highest hardness, H, of 412 +/- 2.9 GPa in combination with a low indentation modulus, E, of 440 +/- 15 GPa is obtained for Mo0.39Al0.52Cr0.09N0.98, possessing also the highest H/E- and H-3/E-2-ratios of 0.1 and 036 GPa, respectively. Further Al-enrichment (x>similar to 0.6) favours, however, the hexagonal phase formation, drastically decreasing the hardness to similar to 20 GPa. Therefore, the combination of excellent mechanical properties with a high Al-content suggests fcc-Mo1-x-yAlxCryNz for severe applications. (C) 2017 Acta Materialia Inc. Published by Elsevier Ltd.

【 授权许可】

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