In-situ desizing for liquid infusion processes
A method of molding a component includes the steps of providing a plurality of fibers, applying the fibers with a low temperature sizing to form a plurality of sized fibers, forming a preform from the plurality of sized fibers, placing the preform in a mold, and de-sizing the preform by heating the mold to an initial temperature that is sufficient to break down the low temperature sizing to a gaseous phase. A molding apparatus is also disclosed.
1. A method of molding a component comprising the steps of:
(a) providing a plurality of fibers;
(b) applying the fibers with a low temperature sizing to form a plurality of sized fibers;
(c) forming a preform from the plurality of sized fibers;
(d) placing the preform in a mold; and
(e) de-sizing the preform by heating the mold to an initial temperature that is sufficient to break down the low temperature sizing to a gaseous phase.
2. The method according to claim 1 , wherein the plurality of fibers are high temperature fibers formed from a material that is capable of being processed at a temperature that is 600 degrees Fahrenheit or greater.
3. The method according to claim 2 , wherein the plurality of fibers are comprised of a polyimide-matrix composite material.
4. The method according to claim 2 , wherein the low temperature sizing is comprised of a material capable of complete decomposition at temperatures less than 850 degrees Fahrenheit.
5. The method according to claim 1 , including (f) removing the gaseous phase of the low temperature sizing from the mold via at least one of a vacuum pressure and a positive pressure.
6. The method according to claim 5 , including (g) heating the mold to an infusion temperature and injecting an infusion liquid to completely infuse the preform with the infusion liquid.
7. The method according to claim 6 , including (h) heating the mold to a curing temperature for a predetermined period of time to provide a cured preform.
8. The method according to claim 1 , wherein the preform is comprised of a non-pre-impregnated material.
9. The method according to claim 1 , wherein the preform comprises a three-dimensional dry-shaped preform.
10. The method according to claim 9 , wherein the dry-shaped preform is formed by at least one of braiding and weaving.
11. The method according to claim 1 , wherein the preform comprises a stack of tackified fabric.
12. A method of molding a component comprising the steps of:
(a) providing a plurality of fibers;
(b) applying the fibers with a low temperature sizing to form a plurality of sized fibers;
(c) forming a preform from the plurality of sized fibers;
(d) placing the preform in a mold;
(e) de-sizing the preform by heating the mold to an initial temperature that is sufficient to break down the low temperature sizing to a gaseous phase;
(f) removing the gaseous phase of the low temperature sizing from the mold;
(g) heating the mold to an infusion temperature and injecting an infusion liquid to infuse the preform; and
(h) heating the mold to a curing temperature to form a cured polyimide-matrix composite material.
13. The method according to claim 12 , wherein step (g) is performed subsequent to step (f).
14. The method according to claim 12 , wherein the low temperature sizing is comprised of a material capable of complete decomposition at temperatures less than 850 degrees Fahrenheit.
15. The method according to claim 14 , wherein the infusion liquid is resin.
16. The method according to claim 14 , wherein step (f) includes removing the gaseous phase with a vacuum pump.
17. The method according to claim 14 , wherein the plurality of fibers are high temperature fibers formed from a material that is capable of being processed at a temperature that is 600 degrees Fahrenheit or greater.
18. The method according to claim 17 , wherein the plurality of fibers are comprised of a polyimide-matrix composite material.