COMPOSITION OF POWDER MIXTURE FOR THERMODIFFUSION TREATMENT OF STEEL ITEMS, METHOD OF THERMODIFFUSION TREATMENT OF STEEL PRODUCTS

摘要

FIELD: chemistry.;SUBSTANCE: invention relates to thermodiffusion treatment of articles in powdered mixtures. It can be used for increase of corrosion resistance of parts and units of mechanisms operating in aggressive media, in particular, oil and gas industry equipment operated in medium containing hydrogen sulphide. Composition of the powder mixture contains zinc and aluminium powders, an activator, that is a mixture of silicocalcium, sodium fluoride, silicon metal, iron oxide, ammonium chloride, lithium chloride, potassium chloride, zinc chloride, an inert filler - silicon oxide, quartz sand or a mixture thereof. Method of thermal diffusion treatment of articles by said saturating powder mixture is carried out by stepwise heating first at temperature of 400–450 °C for 25–30 minutes, then at temperature 500–550 °C for 30–35 minutes.;EFFECT: higher corrosion resistance of parts and units of mechanisms operating in medium containing hydrogen sulphide.;2 cl, 4 tbl, 7 ex