Impact-sliding wear properties of PVD CrN and WC/C coatings

Multilayer CrN/CrAlN coatings were deposited on the 420-SS by the cathodic arc evaporation system with different duty cycles of bias-voltage. The deposited films were characterized by XRD and FESEM techniques. Mechanical, electrochemical, and surface properties of deposited films were studied by nano-indentation, electrochemical, and AFM analysis. Microstructure investigation confirmed the formation of adhesive and dense nanostructure multilayer film.Increasing the duty cycle led to the decrease in the coating grain size and promoted the hardness to 34.1 ± 4 GPa. A clear reduction of size and distribution of macroparticles was observed by using large repulsive force at a high duty cycle. By increasing the duty cycle, the coating deposition rate was increased from 1.23 to 1.38 µm/h and the surface roughness was decreased from 155 to 70 nm. The lower corrosion current density was obtained for the film applied at the 40% duty cycle (0.59 µA cm −2 ), which was about 10-order of magnitude less than the substrate.

Section: Microstructure Investigationmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

The effect of duty cycle on the mechanical and electrochemical corrosion properties of multilayer CrN/CrAlN coatings produced by cathodic arc evaporation

Baseri

Mohammadi

Ghatee

et al. 2020

“…So, porosity (black spots) was found in the Irregular-WC coating shown in Figure 7(b) and Figure 3(b). Therefore, the dissolution mechanism of irregular WC particles was: (1) The sharp edges of irregular WC particles first dissolved; (2) the dissolved free C atoms would partly adhere to the flat interface with small-becoming curvature of irregular WC particles, and a concentration of C was formed at the surface of irregular WC particle; (3) the concentrated C at the surface of WC reacted with O element and oxidation occurred. This dissolution mechanism of irregular WC particles can be concluded as decarburization and oxidation.…”

Section: Dissolution Mechanism Of Wc Particlesmentioning

confidence: 99%

“…In aerospace, mining, metallurgy and other applications, the wear of part surface is one of the main causes of material failure. The metal matrix composite coating with tungsten carbide (WC) as the reinforcement, which combines the advantages of metallic and ceramic materials, exhibits good strength, toughness, hardness and wear resistance [1]. It is widely used to protect the parts, strengthen the surface and repair the worn parts and is of great significance to increase the service life of parts, reducing material consumption and improving production efficiency [2][3][4].…”

Section: Introductionmentioning

confidence: 99%

Microstructures and wear-resistance of WC-reinforced high entropy alloy composite coatings by plasma cladding: effect of WC morphology

Peng

Zhang

et al. 2020

WC-reinforced FeCoCrNi high entropy alloy (HEA) composite coatings with different WC morphology of spherical and irregular shape, were prepared by plasma cladding. The effects of WC morphology on carbide evolution, WC dissolution, and the wear resistance of the coatings were investigated. The results indicated that the evolution of the massive and fishbone M 6 C carbides were significantly influenced by the WC morphology, due to the different curvature radius of WC particles. The dissolution mechanism of spherical WC was diffusion, which of irregular WC was decarburization and oxidation. Although irregular WC particles were broken due to the WC→W 2 C transformation, the wear resistance of the coating with irregular WC was relatively stable, only slightly lower than that of spherical WC, because the developed fish-bone carbide in HEA matrix resisted the three-body abrasive wear of broken WC and W 2 C fragments.

“…The low friction and long life of the coating are attributed due to the transfer behaviour of the coating and polishing action on the counter surface which reduces the sliding and rolling friction. For tool applications where the surface undergoes high contact stress and shear force, such carbon-based coatings show better performance than any other commercial coating such as CrN coatings [25,26].…”

Section: Introductionmentioning

confidence: 99%

Effect of WC/C coated rolling element to improve bearing life

Jain¹,

Vashishtha²,

P³

2023

The research is aimed to understand the effect of WC/C coating on the bearing rolling elements to improve fatigue life in surface distress conditions. The 1-1.5 microns optimized coating thickness was deposited on the steel substrate using the PVD process. The coating's physical and chemical properties were analysed by X-ray diffraction, scanning electron microscope, contact profilometer, nanoindentation hardness, and micro scratch indenter. The wear properties were compared on a ball-on-disc tribometer with and without a coated specimen. The bearing tests were performed in contaminated and clean lubrication conditions to prove the coating's effect on bearing life in surface distress conditions. Results show that coated roller bearings perform at least two times that of the standard bearing. The overall benefit of less friction and wear resistance was due to the polishing action and coating transfer mechanism of multi-layer coating which increases oil film thickness between contacts and hence improve bearing life.