Effects of Ti alloying of AlCrN coatings on thermal stability and oxidation resistance

THIN SOLID FILMS

卷:534

Article

Forsen, R.¹  Johansson, M. P.^1,2  Oden, M.¹  Ghafoor, N.¹ 

[1] Linkoping Univ, Dept Phys Chem & Biol IFM, S-58183 Linkoping, Sweden

[2] Seco Tools AB, S-73782 Fagersta, Sweden

关键词: Age hardening;    Spinodal decomposition;    Hard coatings;    TiAlN;    TiCrAlN;    Catodic arc evaporation;   

DOI  :  10.1016/j.tsf.2013.03.003

来源: Elsevier

【 摘 要 】

Quaternary cubic (TixCr1-xAl-0.60)(1) N-1 coatings with 0 < x < 0.33 have been grown using reactive cathodic arc evaporation. When adding Ti the hardness was retained after annealing up to 1100 degrees C which is a dramatic improvement compared to CrAlN coatings. The coatings showed an age hardening process caused by spinodal decomposition into coherent TiCr-and Al-rich cubic TiCrAlN domains and the formation of hexagonal AlN precipitates and cubic TiCrN domains in the vicinity of the grain boundaries. The improved hardness was attributed to the stabilization of the cubic structure suppressing the formation and growth of hexagonal AlN. Furthermore, the presence of Ti atoms generated incoherent nanometer-sized crystallites within the hexagonal AlN precipitates disrupting the hexagonal lattice during the coarsening process. The addition of Ti promoted the formation of a TiO2 layer over Al2O3 resulting in a lower oxidation resistance. However, by tuning the composition it is possible to design coatings to have both good oxidation resistance and good high temperature mechanical stability. (C) 2013 Elsevier B.V. All rights reserved.

【 授权许可】

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