Freeze drying of composites for filament spreading

A method of manufacturing a ceramic matrix composite, the method comprising:

• forming a fiber preform;
• applying an aqueous solution to a fiber preform, wherein:
• the aqueous solution comprises water and a cryoprotectant;
• the fiber preform comprises a plurality of fiber tows;
• freezing the fiber preform after applying the aqueous solution, wherein freezing the fiber preform spreads filaments within the plurality of fiber tows;
• freeze drying the fiber preform to remove water from the fiber preform;
• heating the fiber preform to remove cryoprotectant from the fiber preform after freeze drying;
• and
• densifying the fiber preform after heating the fiber preform.