A method for densifying porous annular substrates having a central passage by chemical vapor infiltration, the method including providing stacks of porous annular substrates, providing a plurality of individual modules including stacks disposed on a support plate having a perforated injection tube each mounted on a gas inlet opening, forming a stack of individual modules, aligning the individual modules of the stack in a sealed manner by means of an annular seal disposed between the injection tubes of a second individual module and the gas inlet openings of a first individual module with which it cooperates, and injecting into the internal volume of each stack of porous annular substrates a gas phase including a gaseous precursor of a matrix material to be deposited within the porosities of the substrates.

A shape-stable structure that is configured to provide ablative cooling. The structure is used to form a component that includes shape-stable bulk structure and an ablative material. The bulk structure is infiltrated with the ablative material so that the ablative material is disposed in pathways defined by the bulk structure.