Study of the structure, properties, scratch resistance and deformation behaviour of graded Cr-CrN-Cr(1-x)AlxN coatings
Document Type
Journal Article
Publication Title
Ceramics International
Publisher
Ceramics International
School
School of Engineering
RAS ID
27275
Abstract
An in-depth investigation of the structure, properties, scratch adhesion characteristics of graded Cr-CrN-Cr(1-x)AlxN coatings synthesized onto M42 steel substrates using closed – field unbalanced magnetron sputtering (CFUBMS) was carried out. Advanced microscopy (scanning and transmission electron microscopy), focused ion beam (FIB) imaging, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and micro–scratch tests was used to investigate the microstructure, mechanical properties and scratch performance as a function of Al content. FIB and TEM investigations revealed that the coatings exhibited a distinct structure; i.e., an adhesive Cr layer, a CrN transition layer and a graded CrAlN top layer with a face centered cubic (FCC) B1 structure. A columnar morphology was exhibited by the coatings and the dimensions of the columnar grains decreased with increasing Al content. Residual stress measurements, obtained from the XRD – sin2ψ method, revealed increasing compressive stresses with increasing Al content. Furthermore, nanoindentation tests showed an increase in mechanical properties, fracture toughness index (H/E) and plastic deformation resistance (H3/E2) as the Al content increased, accompanied by a decrease in the critical load, LC, during scratch testing implying a decrease in scratch toughness.
DOI
10.1016/j.ceramint.2018.03.187
Access Rights
subscription content
Comments
Kabir, M. S., Munroe, P., Zhou, Z., & Xie, Z. (2018). Study of the structure, properties, scratch resistance and deformation behaviour of graded Cr-CrN-Cr (1-x) AlxN coatings. Ceramics International, 44(10), 11364-11373.
Available here.