Kinetics of V(N,C) and Nb(N,C) coatings produced by V–Nb–RE deposition technique

Kinetics of niobium carbide reinforced composite coating produced in situ

“…Like conventional diffusion methods, the ISS process diffuses elements in the treating agent into the substrate surface in situ producing a coating. It accelerates NbC formation and decreases the activation energy of NbC layer in comparison with other kinetic studies [7,9].…”

“…These coatings are fabricated by surface modification methods, such as laser treatment [3], plasma jet cladding [4], chemical vapor deposition [5], physical vapor deposition [6], thermo-reactive deposition (TRD) [7], and in situ synthesis (ISS) techniques [8]. However, while some of these techniques may achieve good results, distinct disadvantages, such as high costs, complex equipment, operational difficulties, or limitation of the coating thickness (d) [2,9], have also been observed; these disadvantages greatly restrict the wider industrial application of these coatings. Recent developments in the ISS technique have indicated that this approach is inexpensive and offers fine ceramic grains, strong interfacial bonding between the substrate and reinforcement phase, and excellent mechanical properties [10].…”

“…Consequently, NbC is deposited and dispersed in a Fe substrate from the surface to tens of microns deep, which helps improve the surface hardness and modulus of elasticity of materials [9,12]. Several studies have been performed to investigate the mechanism of NbC coating formation as well as the microstructure and microhardness of the coatings produced on steel [12e14].…”

Duplex ceramic coating produced by low temperature thermo-reactive deposition and diffusion on the cold work tool steel substrate: Thermodynamics, kinetics and modeling

“…It has been reported that vanadium carbide/carbonitride/ nitride coatings grow at a faster rate by pre-treating with carburizing, nitrocarburizing and/or nitriding [12]. This is due to the fact that pre-treatment raises the concentration of interstitials in the surface of the substrate prior to TD treatment.…”

“…This is due to the fact that pre-treatment raises the concentration of interstitials in the surface of the substrate prior to TD treatment. Chicco et al [12] carburized H13 tool steel by following TD vanadizing to yield a vanadium carbide coating with the thickness of 4.6 μm. Even thicker coatings are achievable with pre-nitrocarburizing and pre-nitriding because vanadium has a higher affinity for nitrogen rather than carbon.…”