Artigo de peri??dico
Thick CrN/NbN multilayer coating deposited by cathodic arc technique
Registro en:
1516-1439
1
20
10.1590/1980-5373-MR-2016-0293
20.526
Autor
ARAUJO, JULIANO A.
SOUZA, ROBERTO M.
LIMA, NELSON B. de
TSCHIPTSCHIN, ANDRE P.
Resumen
The production of tribological nanoscale multilayer CrN/NbN coatings up to 6 ??m thick by
Sputtering/HIPIMS has been reported in literature. However, high demanding applications, such as
internal combustion engine parts, need thicker coatings (>30 ??m). 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 ??m 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 rocksalt
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. Funda????o de Amparo ?? Pesquisa do Estado de S??o Paulo (FAPESP) FAPESP: 12/50890-0