METHOD OF SINGLE STAGE DIFFUSION CHROME ALUMINISING OF PARTS OUT OF HEAT-RESISTANT ALLOYS Russian patent published in 2016 - IPC C23C10/56 

FIELD: metallurgy.

SUBSTANCE: parts are heated to temperature of diffusion saturation and held in circulating halide environment created upon contact of the input gaseous environment with sources of diffusible elements, ferroaluminium and chrome are used as such elements. The diffusion saturation is performed in mixture additionally containing ammonium chloride, nickel-yttrium and aluminium oxide, at the following ratio of elements wt %: ferroaluminium 38-50, chrome 23-27, ammonium chloride 2.0-5.0, nickel-yttrium 12-19, and aluminium oxide - rest. Heating is performed initially to 1000°C with holding for 6-12 h, them temperature is increased to 1050°C with holding at it for 6-14 h, at that at each heating stage during the diffusion holding the uniform circulation of the halide environment is performed. In particular case of invention implementation at each heating stage during the diffusion holding the circulating halide environment is additionally cleaned of the reacted mixture.

EFFECT: stability of composition, and coating thickness at all treated parts of charge regardless of place of location in the reaction chamber.

2 cl, 1 dwg, 1 tbl, 1 ex