Method for fabricating reinforced composite materials

A method for fabricating a reinforced matrix composite, comprising:

• providing a fibrous composite preform comprising at least one surface having a midpoint, a first edge and a second edge along a centerline;
• applying a preselected amount of matrix material having a preselected curing temperature onto the preform at preselected locations along the preform;
• orienting the preform vertically along the axis with the first edge above the midpoint and the second edge below the midpoint;
• reducing pressure to the first edge;
• providing fluid communication from the first edge to the second edge;
• heating the composite preform to a preselected temperature, the preselected temperature being sufficient to render the matrix material viscous and insufficient to cure the matrix material;
• collecting matrix material flowing from the second edge;
• circulating matrix material collected from the second edge to the first edge through the fluid communication;
• maintaining the reduced pressure and the first temperature until the matrix material has been distributed across the preform substantially uniformly;
• heating the preform to a second preselected temperature, the second temperature being sufficient to cure the matrix material;
• and
• thereafter cooling the preform to form a reinforced matrix composite having a low void content and a substantially uniform matrix distribution.

A method for fabricating a reinforced matrix composite part for a gas turbine engine, comprising:

• providing a tool having a tool surface;
• positioning a composite preform on at least a portion of the tool surface, the preform comprising a center, a first edge and a second edge;
• attaching a plurality of plates to the tool surface, each plate comprising a first and second surface;
• positioning the plates with each second surface adjacent to at least a preselected portion of the composite preform;
• the plates being comprising a material having a thermal coefficient of expansion greater than the thermal coefficient of expansion of the composite preform;
• the tool being comprising a material having a thermal coefficient of expansion greater than the thermal coefficient of expansion of the composite preform;
• providing a matrix material having a preselected curing temperature;
• applying the matrix material onto predetermined locations on the preform to form a coated preform, wherein a greater amount of matrix material is placed on the center of the preform than on each of the first and second edges;
• applying a layer of barrier material to at least a portion of the coated preform that isolates the matrix material from an external environment and enables flow of matrix material from the center to the first and second edges;
• providing a vacuum membrane;
• placing the tool and preform into a vacuum membrane;
• heating the composite preform to a preselected temperature, the preselected temperature being sufficient to render the matrix material viscous, but below the curing temperature of the matrix material;
• holding the temperature at the preselected temperature to flow the matrix material from the predetermined locations into the composite preform;
• the first preselected temperature also being sufficient to cause thermal expansion of the tool and the plates that is greater than the thermal expansion of the composite preform;
• the thermal expansion of the tool and the plate relative to the composite preform being sufficient to cause tensional force across the composite preform;
• applying reduced pressure to an interior of the vacuum membrane sufficient to draw gas from the edges of the preform;
• applying increased pressure to the exterior of the vacuum membrane to apply force across the first surface of the plate through the membrane, thereby creating a pressure differential;
• the reduced pressure to the interior of the vacuum membrane and the increased pressure to the exterior of the vacuum membrane facilitate the flow of the matrix material into the composite preform as a result of the pressure differential, while maintaining the positioning of the preselected portion of the composite preform adjacent to the plurality of plates;
• collecting matrix material flowing from one of the first edge or the second edge;
• distributing the matrix material collected to the one of the first edge or the second edge from which excess material was not drawn;
• heating the preform to a preselected second temperature;
• the second temperature being sufficient to cure the matrix material;
• and
• thereafter cooling the preform to form a reinforced matrix composite having a low void content and a substantially uniform matrix distribution.