Tailoring CrNx stoichiometry and functionality by means of reactive HiPIMS

SURFACE & COATINGS TECHNOLOGY

卷:401

Article

Sanchez-Lopez, J. C.¹  Caro, A.¹  Alcala, G.²  Rojas, T. C.¹ 

[1] Univ Seville, CSIC, Inst Ciencia Mat Sevilla, Avda Americo Vespucio 49, Seville 41092, Spain

[2] Univ Complutense Madrid, Fac Chem, Dept Chem & Mat Engn, Ciudad Univ S-N, Madrid 28040, Spain

关键词: HiPIMS;    Duty cycle;    Pulse;    Oxidation resistance;    Hardness;    Bias;   

DOI  :  10.1016/j.surfcoat.2020.126235

来源: Elsevier

【 摘 要 】

This work presents a complete study of the influence of HiPIMS pulse characteristics on the microstructure, chemical composition, mechanical and oxidation resistance properties of CrN thin films. The investigated parameters were frequency and pulse length at two different nitrogen fluxes, maintaining constant the duty cycle conditions (2%). The effect of a negative bias of 100 V was investigated in a particular case. By changing the synthesis conditions, it was possible to tailor the N/Cr ratio and thus to control the CrNx stoichiometry from x = 0.63 to 1.10. The selection of longer pulses (shorter frequencies) generates more disordered structures with lower N/Cr ratios. This is reflected in higher hardness and elastic modulus values on despite of a lower oxidation resistance due to existence of larger concentration of N vacancies. The best oxidation resistance is obtained at the highest peak current combined with additional ion bombardment provided by substrate biasing. The present results open the possibilities of modifying chemical composition and engineering surfaces by changing exclusively the pulse conditions in HiPIMS deposition processes.

【 授权许可】

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