US 11,858,862 B1
Method of producing machined CMC surfaces without exposing fiber
Jeffrey Crutchfield, Cypress, CA (US); Pathikumar Sellappan, Cypress, CA (US); Chris Downie, Cypress, CA (US); Christopher Mara, Cypress, CA (US); and Sungbo Shim, Cypress, CA (US)
Assigned to ROLLS-ROYCE HIGH TEMPERATURE COMPOSITES INC., Huntington Beach, CA (US)
Filed by Rolls-Royce High Temperature Composites Inc., Cypress, CA (US)
Filed on Jul. 22, 2022, as Appl. No. 17/871,401.
Int. Cl. C04B 35/80 (2006.01); C04B 35/657 (2006.01); C04B 35/628 (2006.01)
CPC C04B 35/80 (2013.01) [C04B 35/62884 (2013.01); C04B 35/62892 (2013.01); C04B 35/62894 (2013.01); C04B 35/62897 (2013.01); C04B 35/657 (2013.01); C04B 2235/5252 (2013.01); C04B 2235/612 (2013.01); C04B 2235/616 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method to produce a ceramic matrix composite part, the method comprising:
providing a ceramic fiber preform, the ceramic fiber preform including a three-dimensional framework of a plurality of ceramic fibers;
prior to melt infiltration, adding a layer of machinable stock to only a target area of the ceramic fiber preform, wherein the target area comprises less than a total surface area of the ceramic matrix composite part;
melt infiltrating the ceramic fiber preform;
forming the ceramic matrix composite part by cooling the melt infiltrated ceramic fiber preform;
machining the part in the target area where the machinable stock is located; and forming a precision feature in the machinable stock disposed on the target area.