METHOD FOR FORMING A LAYER OF A SINGLE-PHASE OXIDE (Fe,Cr)O WITH A RHOMBOHEDRAL STRUCTURE ON A SUBSTRATE MADE OF STEEL OR A HEAT-RESISTANT ALLOY Russian patent published in 2022 - IPC C23C8/02 C23C8/14 C23C8/80 F24S70/30 

FIELD: shaping.

SUBSTANCE: group of inventions relates to a method for forming a layer of a single-phase oxide (Fe,Cr)₂O₃ with a rhombohedral structure on a substrate made of steel or a heat-resistant alloy, a solar absorber and a method for manufacture thereof. The method for forming a layer of a single-phase oxide (Fe,Cr)₂O₃ with a rhombohedral structure with a thickness from 70 nm to 150 nm on a substrate made of steel or a heat-resistant alloy includes the following sequential stages: a) producing a substrate made of steel or a heat-resistant alloy with a surface layer, wherein the steel comprises at least 2 wt.% chromium, b) removing the surface layer before reaching the substrate in an atmosphere containing at least 0.2 atm of dioxygen, providing a level of micro-deformations in the crystal lattice of the steel or the heat-resistant alloy of more than 1.0×10^-3 and heating locally at a rate of more than 400°C/s in order to form a layer of a single-phase oxide (Fe,Cr)₂O₃ with a rhombohedral structure, c) performing heat treatment in air at a partial water pressure of less than 10,000 million^-1 and at a temperature from 400°C to 1,000°C in order to grow a layer of a single-phase oxide (Fe, Cr)₂O₃ with a rhombohedral structure, formed at stage b).

EFFECT: formation of a layer of a single-phase oxide (Fe, Cr)₂O₃ with a controlled crystallographic structure and an adjustable thickness of 70 to 150 nm on the surface of a substrate made of steel or a heat-resistant alloy.

16 cl, 10 dwg, 2 tbl