Commissariat &#xc0; L'&#xc9;nergie Atomique Et Aux &#xc9;nergies Alternatives

Commissariat a L'energie Atomique

Mannesmann Precision Tubes France

Olivier Sicardy

Christophe Dubarry

Olivier Raccurt

Gatien Fleury

Raphaël Couturier

Benoit Boulay

Carole Mollard

Francis Bourguignon

Pierre-Jean Marchais

A method for forming a layer of single-phase oxide (Fe, Cr)Owith a rhombohedral structure on a steel or super alloy substrate, may include, successively: (a) supplying a steel or super alloy substrate covered with a surface layer, the steel including at least 2 wt.-% chromium; (b) removing the surface layer in an atmosphere containing at least 0.2 atm O, creating a level of micro-deformation in the crystal lattice of the steel or super alloy that is greater than 1.0.10, and a heating at a heating rate higher than 400° C./s, such as to form a layer of rhombohedral oxide () (Fe, Cr)O; and (c) carrying out a thermal treatment, in the presence of air, at a water partial pressure of less than 10.000 ppm, and at a temperature varying in a range of from 400 to 1000° C., such as to grow the layer of rhombohedral oxide formed in the removing (b) to a thickness in a range of from 70 to 150 nm.

Method for forming a layer of single-phase oxide (Fe, Cr)Owith a rhombohedral structure on a steel or super alloy substrate

A solar radiation absorber element for a thermal concentrating solar power plant is achieved by forming a selective coating on an outer surface of a substrate made from stainless steel, chosen from stainless steels presenting an aluminum content of more than 0.5% by weight. Formation of the selective coating includes a surface treatment step of the substrate, by polishing, and a heat treatment step of the substrate, in an oxidizing atmosphere, in a temperature range included between 550&#xb0; C. and 650&#xb0; C. The heat treatment in particular enables at least one intrinsically selective superficial thin layer to be formed on the outer surface of the substrate.

Process for producing an element for absorbing solar radiation for a thermal concentrating solar power plant

A crystallization method, including: depositing a thin film of a crystalline material on a substrate; heating the substrate and the crystalline material deposited on the substrate to a first temperature for a time enabling internal strains present in the crystalline material to be relaxed; after the heating, subjecting the substrate and the crystalline material to a second temperature and to a uniform bending by placing the substrate on a bending bench, a quantity of bending and a difference between the first and the second temperature having values determined from elastic bending constants, thermal deformations and thermal expansion coefficients to favor a particular crystallographic orientation of the crystalline material along an azimuth direction in relation to a direction normal to the substrate.

Crystallisation method with control of the orientation of the crystal grains

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Saint-Egrève, France

Olivier Sicardy