Phase stability and alloy-related trends in Ti-Al-N, Zr-Al-N and Hf-Al-N systems from first principles

SURFACE & COATINGS TECHNOLOGY

卷:206

Article

Holec, David¹  Rachbauer, Richard¹  Chen, Li^1,2  Wang, Lan¹  Luef, Doris¹  Mayrhofer, Paul H.¹ 

[1] Univ Leoben, Dept Phys Met & Mat Testing, A-8700 Leoben, Austria

[2] Cent S Univ, State Key Lab Powder Met, Changsha 410083, Hunan, Peoples R China

关键词: Density functional theory (DFT);    Hard coatings;    TiAlN;    ZrAlN;    HfAlN;   

DOI  :  10.1016/j.surfcoat.2011.09.019

来源: Elsevier

【 摘 要 】

Transition metal aluminium nitride (TM-Al-N) thin films are valued for their excellent mechanical (e.g. hardness) as well as protective (e.g. oxidation resistance) properties. This paper addresses the structure and phase stability of group IVB TM-Al-N systems Ti(1-x)Al(x)N, Zr(1-x)Al(x)N, and Hf(1-x)Al(x)N. The predicted stability regions of the rock salt cubic structures are x <= 0.7, x <= 0.45, and x <= 0.45, respectively, while the wurtzite-type single phase field is obtained for x >= 0.7, x >= 0.68, and x >= 0.62 respectively. The predicted phase stability regions and the broad dual-phase transition regions in the case of Zr(1-x)Al(x)N and Hf(1-x)Al(x)N are validated by experiments. Furthermore, the phase transition from cubic to wurtzite with increasing Al content in the alloys is correlated with changes of electronic structure and bonding in the systems. (C) 2011 Elsevier B.V. All rights reserved.

【 授权许可】

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