Thick CrN/NbN Multilayer Coating Deposited by Cathodic Arc Technique

Autor(es)

Juliano Avelar Araujo ^[1] ; Roberto Martins Souza ^[2] ; Nelson Batista de Lima ^[3] ; André Paulo Tschiptschin

Afiliação do(s) autor(es)

^[1] University of São Paulo. Metallurgical and Materials Engineering Department - Brasil

^[2] University of São Paulo. Mechanical Engineering Department - Brasil

^[3] Nuclear and Energy Research Institute. Department of Materials Characterization - Brasil

• Tipo de documento: Artigo Científico
• Fonte: MATERIALS RESEARCH-IBERO-AMERICAN JOURNAL OF MATERIALS; v. 20, n. 1, p. 200-209, 2016-12-19.

Resumo

The production of tribological nanoscale multilayer CrN/NbN coatings up to 6 µm thick by Sputtering/HIPIMS has been reported in literature. However, high demanding applications, such as internal combustion engine parts, need thicker coatings (>30 µm). The production of such parts by sputtering would be economically restrictive due to low deposition rates. In this work, nanoscale multilayer CrN/NbN coatings were produced in a high-deposition rate, industrial-size, Cathodic Arc Physical Vapor Deposition (ARC-PVD) chamber, containing three cathodes in alternate positions (Cr/Nb/Cr). Four 30 µm thick NbN/CrN multilayer coatings with different periodicities (20, 10, 7.5 and 4 nm) were produced. The coatings were characterized by X-Ray Diffraction (XRD) and Transmission Electron Microscopy (TEM). The multilayer coating system was composed of alternate cubic rock-salt CrN and NbN layers, coherently strained due to lattice mismatch. The film grew with columnar morphology through the entire stratified structure. The periodicities adopted were maintained throughout the entire coating. The 20 nm periodicity coating showed separate NbN and CrN peaks in the XRD patterns, while for the lower periodicity (≤10nm) coatings, just one intermediate lattice (d-spacing) was detected. An almost linear increase of hardness with decreasing bilayer period indicates that interfacial effects can dominate the hardening mechanisms. (AU)

• Processo FAPESP: 12/50890-0 - Improvement of surface properties of stainless steel used in the oil and gas industries through plasma assisted thermochemical treatment
• Beneficiário: Andre Paulo Tschiptschin
• Modalidade de apoio: Auxílio à Pesquisa - Regular