Process for injection moulding a composite part

Patent metadata

Field	Value
Publication number	US-9669570-B2
Application number	US-201214116068-A
Country	US
Kind code	B2
Filing date	May 2, 2012
Priority date	May 6, 2011
Publication date	Jun 6, 2017
Grant date	Jun 6, 2017

Abstract

A method of injection molding a part made of composite material is provided. The method includes placing a preform in a mold; injecting a resin into the mold so as to impregnate the preform; unmolding the part after curing the resin; and subjecting the resin and the preform to pressure inside the mold while the resin is curing.

First claim

The invention claimed is:

1. A method of injection molding a blade comprising a composite material, the method comprising:
placing a blade fiber preform in a mold, the blade fiber preform being formed by weaving yarns and including a root portion having a first planar sloping face, a second planar sloping face, and a bottom planar face between the first and second sloping faces in a cross-sectional view, and an airfoil portion having a leading edge and a trailing edge;
injecting a resin into the mold so as to impregnate the blade fiber preform;
unmolding the blade after curing the resin; and
subjecting the resin and the blade fiber preform to pressure inside the mold while the resin is curing,
wherein the blade is free of pores,
wherein the mold includes a resin injection hole facing the bottom planar face of the root portion and a vent hole facing a tip of the airfoil portion, a first gas injection hole facing the leading edge of the airfoil portion, and a second gas injection hole facing the trailing edge of the airfoil portion, and
wherein the pressure is applied to the blade fiber preform by injecting a fluid under pressure into the mold via the first gas injection hole and the second injection hole.

2. The method according to claim 1 , wherein the pressure is applied to the blade fiber preform in the mold before a degree of curing of the resin exceeds a value of from 20% to 30%.

3. The method according to claim 1 , wherein the pressure applied to the blade fiber preform in the mold is higher than a vapor pressure of a gas generated during curing of the resin.

4. The method according to claim 1 , wherein the pressure applied to the blade fiber preform is greater than or equal to 2 bars, relative to atmospheric pressure.

5. The method according to claim 1 , wherein the resin is an epoxy resin, a bismaleimide resin, a polyimide resin, or any resin comprising volatile impurities, solvents, or both.

6. The method according claim 1 , wherein the mold is evacuated in order to inject the resin.

7. The method according to claim 1 , further comprising a plurality of successive stages of injecting resin into the mold and of pressurizing the resin and the mold.

8. The method according to claim 1 , wherein the fluid injected under pressure is a gas such as air or nitrogen, or a liquid that is not miscible with the resin.

9. The method according to claim 1 , wherein the mold includes recesses corresponding to the first and second sloping faces of the root portion.

10. The method according to claim 1 , wherein the pressure is further applied to the blade fiber preform by injecting the fluid under pressure into the mold via the resin injection hole and the vent hole.

Assignees

• Godon Thierry
• Dambrine Bruno Jacques Gérard
• Ruiz Eduardo Antonio Julian
• Trochu François
• Snecma

Inventors

• Godon Thierry
• Dambrine Bruno Jacques Gérard
• Ruiz Eduardo Antonio Julian
• Trochu François

Classifications

• B29C45/0025 Primary

  Preventing defects on the moulded article, e.g. weld lines, shrinkage marks (preventing defects on the preformed parts or layers B29C45/14836) · CPC title

• B29C70/48 Primary

  and impregnating the reinforcements in the closed mould, e.g. resin transfer moulding [RTM] {, e.g. by vacuum} · CPC title

• B29C70/461 Primary

  Rigid movable compressing mould parts acting independently from opening or closing action of the main mould · CPC title