| 摘要 |
A method of producing a ceramic fiber/ceramic matrix composite having a precracked fiber coating includes depositing a metal coating or a metal nitride or metal carbide coating on each ceramic fiber in a preform of fibers, infiltrating the fiber preform with a ceramic matrix to form a ceramic fiber/ceramic matrix composite, after the formation of the composite is complete, oxidizing the coating so as to change the coating to an oxide thereof. This process forms microcracks throughout the oxidized coating because of the mismatch in characteristics between the precursor layer and the final oxidized layer. An alternative method of producing a ceramic fiber/ceramic matrix composite having a precracked fiber coating includes depositing an oxidation resistant oxide, carbide or nitride which undergoes a destructive phase transformation after the coating and matrix infiltration processes are complete by the use of thermal cycling. This process forms microcracks throughout or around the coating because of the volume change associated with the phase transformation. |
