Pure and Applied Chemistry · 1976 · 29 citations · 7 references
Natural SciencesMaterials EngineeringMaterials ScienceChemical KineticsMetallic MaterialsSurface ScienceCoating ProcessesCoating TechnologyCoatingsHigh-temperature PlasmasPlasma HeatingPlasma-surface InteractionsActivation EnergyBond StrengthPlasma Sprayed CoatingsPlasma SprayingPlasma Treatment Of CompositesPlasma-activated BondingPlasma-assisted BondingPlasma-surface Reactions
Plasma heating and spraying of different materials are considered. Data are given on the energy balance of plasma jets. 1t is shown that, using plasma spraying, one can produce coatings and composite materials. Physicochemical processes causing formation of strong bonds between coating and substrate are considered. Experimental investigations of the rate of increase of bond strength for melted particles which are being sprayed on the polished surface of specimens have shown that the main stage in this process is chemical interaction of a particle and the substrate. Data on interaction of 80 pairs of materials are given. These are activated processes, and the activation may be due to heating of the substrate and overheating of the sprayed particles. The effects of different parameters both on the type of reactions and their kinetics are analysed. The activation energy for the formation of a strong bond between metals by spraying is approximately .half the bond energy of atoms in the metallattice of a substrate.
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