Method for manufacturing a double-layered heat exchange wall

A method for manufacturing a double-layer heat-exchange wall comprising a first layer and a second layer, the first and second layers being metallic, this manufacturing method comprising the following successive steps (i) to (v), and optionally (vi):

• (i) the provision:
• of a first metal sheet intended to form the first layer and having a thickness e1,
• of a second metal sheet intended to form the second layer and having a thickness e2, and
• of a leaf of iron Fe0 having a thickness e3 of between 10 μm and 100 μm and, advantageously, between 50 μm and 100 μm;
• (ii) the assembly of the first and second metal sheets and the leaf of iron Fe0, the leaf being interposed between the first and second metal sheets,
• (iii) the mechanical pressing of the assembly obtained at the end of the previous step at a minimum pressure of 1 MPa;
• (iv) the peripheral welding of the pressed assembly obtained at the end of step (iii);
• (v) the heat treatment of the welded assembly obtained at the end of step (iv), this heat treatment being implemented by hot isostatic pressing conducted at a temperature of between 800° C. and 1200° C., at a pressure of between 108 Pa and 2.108 Pa, for a period of between 1 hour and 3 hours;
• and, optionally,
• (vi) a supplementary treatment such as curving, bending, quenching, normalised ageing or annealing.