Method of manufacturing a ceramic matrix composite

A method of manufacturing a ceramic matrix composite using fibers comprising the steps of:

• (a) forming a slurry comprising a ceramic sol, filler material and a suspension medium,
• (b) forming a plurality of laminates of the fibers,
• (c) applying the slurry to each of the plurality of laminates of fibers,
• (d) stacking the plurality of laminates of fibers on a mold,
• (e) applying pressure to the stack of laminates of fibers at a low temperature to remove the suspension medium from the slurry to solidify the ceramic sol and thereby produce a ceramic matrix composite,
• (f) pressure less sintering the ceramic matrix composite at a high temperature and at atmospheric pressure wherein step (e) further comprises covering the stack with a porous membrane, covering the porous membrane with a breather fabric, covering the breather fabric with a vacuum bag and evacuating the vacuum bag to remove the suspension medium from the slurry to solidify the ceramic sol and thereby produce the ceramic matrix composite, and heating the stack during or after evacuation of the vacuum bag to encourage the solidification of the ceramic sol.

A method of manufacturing a ceramic matrix composite using fibers comprising the steps of:

• (a) forming a slurry comprising a ceramic sol, filler material and a suspension medium,
• (b) forming a plurality of laminates of the fibers,
• (c) applying the slurry to each of the plurality of laminates of fibers,
• (d) stacking the plurality of laminates of fibers on a mold,
• (e) applying pressure to the stack of laminates of fibers at a low temperature to remove the suspension medium from the slurry to solidify the ceramic sol and thereby produce a ceramic matrix composite,
• (f) pressure less sintering the ceramic matrix composite at a high temperature and at atmospheric pressure, wherein the mould is hollow and has an inner surface, the method further comprising stacking the laminates of fibres on the inner surface of the hollow mould.

A method of manufacturing a ceramic matrix composite using fibers comprising the steps of:

• (a) forming a slurry comprising a ceramic sol, filler material and a suspension medium,
• (b) forming a plurality of laminates of the fibers,
• (c) applying the slurry to each of the plurality of laminates of fibers,
• (d) stacking the plurality of laminates of fibers on a mold,
• (e) applying pressure to the stack of laminates of fibers at a low temperature to remove the suspension medium from the slurry to solidify the ceramic sol and thereby produce a ceramic matrix composite,
• (f) pressure less sintering the ceramic matrix composite at a high temperature and at atmospheric pressure, wherein the mould defines an aerofoil shape.

A method of manufacturing a ceramic matrix composite using fibers comprising the steps of:

• (a) forming a slurry comprising a ceramic sol, filler material and a suspension medium,
• (b) forming a plurality of laminates of the fibers,
• (c) applying the slurry to each of the plurality of laminates of fibers,
• (d) stacking the plurality of laminates of fibers on a mold,
• (e) applying pressure to the stack of laminates of fibers at a low temperature to remove the suspension medium from the slurry to solidify the ceramic sol and thereby produce a ceramic matrix composite,
• (f) pressure less sintering the ceramic matrix composite at a high temperature and at atmospheric pressure, wherein the fibres comprise mullite or mullite and alumina, the ceramic sol comprises silica and the filler material comprises alumina.

A method of manufacturing a sandwich structure comprising at least two layers of ceramic matrix composite and a ceramic filler arranged between the at least two layers of ceramic matrix composite, the method comprising the steps of:

• a) forming a mold from a ceramic filler material to a predetermined shape, the mold having spaced apart surfaces,
• b) forming a slurry comprising a ceramic sol, filler material and a suspension medium,
• c) forming a plurality of laminates of fibers,
• d) applying the slurry to each of the plurality of laminates of fibers,
• e) stacking the plurality of the laminates of fibers on the mold, the plurality of laminates being stacked on the spaced apart surfaces of the mold, and
• f) applying pressure to the stack of laminates of fibers to remove the suspension medium from the slurry to solidify the ceramic sol and thereby produce a sandwich structure comprising at least two ceramic matrix composite layers and a ceramic filler material between the at least two layers of ceramic matrix composite,
• wherein the mold is hollow and has an inner surface, the method comprising stacking the laminates of fibers on the inner surface of the hollow mold.