Publication Date: 2003-Apr-23
The IP.com Prior Art Database
Resin transfer molding (RTM) and other molding processes are discussed which utilize secondary materials in conjunction with the primary reinforcing material in molding processes. The molding process permits the tailoring of a molded part to meet specific needs.
Resin transfer molding and other molding processes are discussed. The use of secondary materials in conjunction with the primary reinforcing material in molding processes is presented. The molding process permits the tailoring of a molded part to meet specific needs.
Resin transfer molding (RTM) is a closed mold process applicable to the fabrication of complex, high performance composite articles of both large and small size. There are several different resin transfer molding processes that are well known in the fabrication of composite parts. The RTM process is differentiated from various other molding processes in that the primary reinforcement material, such as fiberglass or other fiber reinforcement material, is placed separately into a molding tool cavity and then combined with resin within the mold cavity to form a fiber reinforced plastic (FRP) composite product.
Typically a three dimensional, preshaped fiber reinforcement (generally referred to as a "preform"), is positioned within a molding tool cavity and the molding tool is then closed. A liquid resin is then injected into the tool cavity where it impregnates and envelops the fiber reinforcement. The liquid resin may be a curable thermosetting resin or a thermoplastic resin. In the case of the thermosetting resin the resin is subsequently cured. In the case of the thermoplastic resin, the mold is cooled below the melt temperature of the resin prior to part removal.
The cured, semi-cured or cooled FRP product (as the case may be) then is removed from the molding tool cavity. In view of the fact that RTM processes allow the placement of various types of fiber reinforcement materials, in the mold cavity with minimal subsequent movement of the reinforcement during injection of the resin, the fiber reinforcemen...