Embossed release film, vacuum bagging system, and methods of fabricating composite parts using the same
An embossed release film for use in a vacuum bagging system during a process of curing a composite part includes a raised pattern defining an upper air pathway and a lower air pathway. The raised pattern defining the upper air pathway and the lower air pathway negates the need for a breather fabric that is included in conventional vacuum bagging systems. Providing a vacuum bagging system without a breather fabric simplifies the vacuum bagging system, satisfies lean manufacturing principles, and reduces cycle time, manufacturing cost, and waste.
1 . A method of fabricating a composite part, the method comprising:
loading a fibrous material of an uncured composite part on a mold;
curing the uncured composite part to form the composite part, wherein the curing the uncured composite part comprises placing the uncured composite part in a vacuum bagging system and placing the vacuum bagging system and the uncured composite part in an oven or an autoclave, wherein the curing generates volatile compounds due to off-gassing of resin in the composite part,
wherein the placing the uncured composite part in the vacuum bagging system comprises:
placing an embossed release film on the uncured composite part, the embossed release film comprising a raised pattern having an irregular arrangement and defining a plurality of pathways extending across the embossed release film;
covering the uncured composite part and the embossed release film with a vacuum bag film; and
sealing the vacuum bag film to the mold; and
evacuating air and the volatile compounds from an interior space between the vacuum bag film and the mold through one or more vacuum ports in communication with interior space utilizing a vacuum pump of the vacuum bagging system during the curing of the uncured composite part, wherein the air and the volatile compounds flow across the embossed vacuum bag film through the plurality of air pathways defined by the embossed release film during the evacuating of the air and the volatile compounds from the interior space; and
removing the composite part from the vacuum bagging system,
wherein the embossed release film self-releases from the composite part,
wherein the vacuum bagging system does not include a breather fabric,
wherein the embossed release film crosses the one or more vacuum ports in a plan view, and
wherein a size and the shape of the plurality of air pathways vary across the embossed release film.
2 . The method of fabricating a composite part of claim 1 , wherein the embossed release film comprises a polyolefin or a fluoropolymer material.
3 . The method of fabricating a composite part of claim 1 , wherein the embossed release film further comprises a release-coating on at least a portion of an inner surface of the embossed release film.
4 . The method of fabricating a composite part of claim 1 , wherein sealing the vacuum bag film to the mold comprises sealing the vacuum bag film to the mold with a tape sealant.
5 . The method of fabricating a composite part of claim 1 , wherein the fibrous materials further comprise layers or plies of fabric or fibrous materials bonded together with a matrix of polymer and arranged in a laminate stack.
6 . The method of fabricating a composite part of claim 5 , wherein the layers or plies of fabric or fibrous materials comprise carbon, fiberglass, aramid, or quartz.
7 . The method of fabricating a composite part of claim 5 , wherein the matrix of polymer comprises epoxy, polyester, vinyl esters, bismaleimides, or benzoxazine.