Microstructure investigation of magnetron sputtered WC/C coatings deposited on steel substrates

The effect of coating architecture and defects on the corrosion behaviour of a PVD multilayer Inconel 625/Cr coating

“…Defects tend to be non-uniformly distributed over the coated surface; the density, shape and size of the defects is dependent on the deposition conditions and the nature of the substrate. Defects can originate from substrate surface irregularities such as pits and asperities, foreign particle contamination on the substrate surface (such as dust and grinding/polishing residues), and from uncontrolled deposition of material from the sputter or evaporation source [8,10,[12][13][14]. It is assumed that large defects are related to the cleanliness of the batching room, and it has been shown that some microscopic particles can remain on the substrate surface even after ultrasonic cleaning [9,12].…”

Nanoindentation Study of PVD WC/C Coatings Supported by Cross-Sectional Electron Microscopy Observations

“…The presence of a brighter band in the coating is due to a higher tungsten concentration. 10 The micrograph clearly establishes that the uplifting of the coating occurred not by interfacial fracture, but by crack propagation inside the coating. Furthermore, the cracks produced by tensile stresses, namely, the ones related to the indentation apex and the through thickness, FIG.…”

“…These defects are created either by substrate surface irregularities or simply by the top morphology of the chromium columns. 10 The explanation for crack propagation in the carbon lamellae (and ultimately leading to decohesion) of coated system S2, and not also of system S1, is related to their multilayers microstructure. From high-resolution TEM it could be learned that the multilayers have a different interlaminar structure.…”

“…A thorough study of the deposition process, microstructure, and chemical composition of the systems has been described elsewhere. 10 Therefore, in this article information is only given about the structure of the systems whenever it is required to understand their surface deformation behavior. The use of different coatings-substrates configurations reveals important clues with respect to the mechanical behavior of the entire coating system.…”

First-principles calculation of W/WC interface: Atomic structure, stability and electronic properties

“…(2) stress relaxation; (3) reduction of porosity; (4) crack deflection [3]. Researchers had attempted to prepare the WC/W bilayer coating [3,4] and WC-Co multilayer coatings [5].…”