Abstract: Process for producing an element comprising a multilayer architecture, the layers of which comprise primary channels on their upper faces, said process comprising the following successive steps: (a) producing secondary channels on the lower faces of each layer, each secondary channel being intended to be facing a primary channel of the neighboring lower layer within the architecture, (b) depositing a coating that protects against oxidation at a temperature of between 500° C. and 1000° C. and against corrosion over all of the lower and upper surfaces of the layers, (c) sanding or mechanical cleaning of the surfaces intended to be assembled, and (d) assembling via superposition of the various layers so that each secondary channel of a lower face of an upper layer is facing and is centered on a primary channel of the neighboring lower layer, the width of each secondary channel being greater than the width of the primary channel which it is facing within the architecture.