Claims
- 1. A method of vacuum assisted resin transfer molding, comprising:
forming a resin transfer assembly by positioning a dry fiber preform on a tool and sealing at least a portion of the dry fiber preform in a vacuum bag; positioning the resin transfer assembly in an autoclave; infusing the resin into the dry fiber preform; vacuum pressurizing a resin outlet line and bleeding resin out of the fiber preform concurrent with pressurizing the resin inlet line; detaching the resin inlet line; and pressurizing the autoclave and bleeding additional resin out of the fiber preform.
- 2. The method of claim 1, further comprising the step of attaching the resin inlet line and the resin outlet line to the resin transfer assembly before pressurizing the inlet and outlet lines.
- 3. The method of claim 1, wherein said steps of pressurizing the inlet and outlet lines result in a fiber volume fraction of at least 53% in the fiber preform.
- 4. The method of claim 3, wherein said step of pressurizing the autoclave results in a fiber volume fraction of at least 57% in the fiber preform.
- 5. The method of claim 1, wherein said step of forming a resin transfer assembly includes positioning a second tool on the portion of the dry fiber preform and sealing the second tool in the vacuum bag along with the portion of the dry fiber preform.
- 6. The method of claim 5, wherein said step of forming a resin transfer assembly further includes rigidly fixing an external locating fixture to the second tool through a hole in the vacuum bag and positioning the second tool within a tight tolerance.
- 7. The method of claim 6, wherein said step of forming a resin transfer assembly further includes sealing the hole in the vacuum bag against airflow with a mounting seal.
- 8. The method of claim 6, wherein said step of positioning the second tool within the tight tolerance includes positioning the tool within ±0.015 inches or less.
- 9. The method of claim 5, wherein said step of forming a resin transfer assembly further includes positioning a mold detail on the second mold line tool at a hard interface between the second mold line tool and the portion of the dry fiber preform.
- 10. The method of claim 1, wherein said pressurizing the autoclave step includes drawing away the additional resin bled from the fiber preform through the resin outlet line.
- 11. A method of manufacturing a resin-impregnated composite, comprising:
encapsulating a dry fiber preform within a fluid-impermeable container; supplying a resin to the fluid-impermeable container and infusing the dry fiber preform with the resin; providing an outlet from the fluid-impermeable container; and applying an external pressure to an external surface of the fluid-impermeable container resulting in an internal pressure increase within the fluid-impermeable container wherein the internal pressure increase is attributable to, and in proportion to, the external pressure increase, said internal pressure increase urging the resin out of the preform and fluid-impermeable container and increasing a fiber-volume fraction of the resin-impregnated composite.
- 12. A method of claim 11, wherein applying the external pressure includes applying an external pressure up to a peak of 100 psi.
- 13. A method of claim 11, wherein supplying the resin includes connecting the fluid-impermeable container to a resin supply and wherein infusing the preform includes supplying a vacuum to the fluid-impermeable container.
- 14. A method of claim 13, wherein the fiber-volume fraction of the composite is 57% or greater.
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a divisional of U.S. application Ser. No. 09/878,825, filed Jun. 11, 2001, which is hereby incorporated herein in its entirety by reference.
FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] The United States Government may have rights in this invention as provided by the terms of Contract No. NAS 1-20546 awarded by the National Aeronautics and Space Administration.
Divisions (1)
|
Number |
Date |
Country |
Parent |
09878825 |
Jun 2001 |
US |
Child |
10752831 |
Jan 2004 |
US |