This Letter describes the theoretical structure of the plasma diffusion layer that develops from an initially sharp gas-metal interface. The layer dynamics under isothermal and isobaric conditions is considered so that only mass diffusion (mixing) processes can occur. The layer develops a distinctive structure with asymmetric and highly nonlinear features. On the gas side of the layer the diffu...

the use of fe-al intermetallic compound coatings has been investigated in order to improve the tribological behaviour of carbon tool steel. the coatings were formed by a pack cementation process and subsequently diffusion annealing at 900˚c in an argon controlled atmosphere. the optimum diffusion time was selected on the basis of optimum thickness and tribological behaviour. the microstructure ...

Abstract: In this research plasma nitriding of pure aluminium and effect of iron elemental alloy on the formation and growth of aluminium nitride was investigated. Also corrosion properties of formed AlN were investigated. After preparation, the samples were plasma nitrided at 550oC, for 6, 9 and 12 h and a gas mixture of 25%H2-75%N2. The microstructure and phases analysis were investigated usi...

radiation enhanced diffusion at the surface of metals has been observed and studied for low-energy nitrogen ions at the surface of copper. the displacement of the target atoms during irradiation creates vacancies and other defects near the surface, thus enhancing the diffusion of implanted materials toward the surface and also into the solid. the mechanism has been studied here by a special met...

Thin-film Si grows layer by layer on Si(001)-(2 × 1):H in plasma-enhanced chemical vapor deposition. Here we investigate the reason why this occurs by using quantum chemical molecular dynamics and density functional theory calculations. We propose a dangling bond (DB) diffusion model as an alternative to the SiH3 diffusion model, which is in conflict with first-principles calculation results an...

Distribution of contact pressure between the bipolar plate and gas diffusion layer considerably affect the performance of proton exchange membrane fuel cell. In this regard, an adaptive neuro-fuzzy inference system (ANFIS) is developed to predict the contact pressure distribution on the gas diffusion layer due to dimensional errors of the bipolar plate ribs in a proton exchange membrane fuel ce...