Toughening mechanisms in V-Si-N coatings

Materials & Design

卷:209

N. Daghbouj¹  Y.J. Feng¹  H.S. Sen²  M. Callisti²  B.S. Li³  T. Polcar⁴  F. Huang⁴  F.F. Ge⁴  P. Zhu⁴  F.P. Meng⁴  P. Li⁵ 

[1] Corresponding authors.;

[2] Department of Control Engineering, Faculty of Electrical Engineering, Czech Technical University in Prague, Technická 2, 160 00 Prague 6, Czechia;

[3] Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS, United Kingdom;

[4] Engineering Laboratory of Advanced Energy Materials, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang, 315201, China;

[5] State Key Laboratory for Environment-friendly Energy Materials, Southwest University of Science and Technology, Mianyang, Sichuan 621010, China;

关键词: Grain boundaries;    Toughening mechanisms;    Superhard nanocomposite;    Physical vapor deposition;    Ab initio simulations;    Friedel oscillations;   

DOI  :  

来源: DOAJ

【 摘 要 】

Microstructural evolution and deformation mechanisms of magnetron sputtered V-Si-N coatings with various Si contents are investigated by transmission electron microscopy, X-ray absorption spectroscopy, and ab initio calculations. A small amount of Si atoms was dissolved into the cubic VN lattice, locally reducing the neighboring V-N p-d hybridization near the Si site. The Si content was found to impact the architecture of coating significantly. With increasing Si content, the microstructure evolved through three different architectures: (i) highly textured columnar grains, (ii) refined columnar grains, and (iii) nanocomposite structures where elongated grains were bounded by vein-like boundaries. Enhanced damage tolerance was observed in the nanocomposite structure, where multiple toughening mechanisms become active. Ab initio calculations revealed that the incorporation of Si monolayer in the (111)-oriented VN resulted in the formation of weaker Si-N bonds compared to V-N bonds, which allowed a selective response to strain and shear deformations by assisting the activation of the slip systems.

【 授权许可】

Unknown