Carbon fiber-filled sheet molding compound and method of manufacturing same
View Patent ↗The present invention involves a carbon fiber-filled sheet molding compound and method of manufacturing the same. The invention comprises providing chopped automotive carbon fibers, a predetermined resin paste, a first carrier film, and a second carrier film. The method further involves coating substantially completely one side of one of the first and second carrier films with the predetermined resin paste to define a coated side, depositing the chopped automotive carbon fibers onto the coated side, and covering the deposited carbon fibers with the second carrier film to define a compactible carbon-filled laminate. The method further includes compacting the carbon-filled laminate to admix the resin paste with the carbon fibers between the films, whereby to form the automotive carbon fiber-filled sheet molding compound.
1. A system for making from laminate an automotive carbon fiber-filled sheet molding compound having the characteristics of light weight, high stiffness and high strength, the system comprising:
a mechanism for providing chopped automotive carbon fibers, a predetermined resin paste, a first carrier film, and a second carrier film;
a mechanism for coating substantially completely one side of one of the first and second carrier films with the predetermined resin paste to define a coated side;
a mechanism for depositing chopped automotive carbon fibers onto the coated side, wherein the coated side is the one side of the first and the second carrier films that is coated substantially completely with the predetermined resin paste;
a mechanism for covering the deposited carbon fibers with the second carrier film to define a compactable carbon-filled laminate; and
a mechanism for compacting the carbon-filled laminate to admix the resin paste with the carbon fibers between the films, whereby to form the automotive carbon fiber-filled sheet molding compound.
2. The system of claim 1 wherein the paste is maintained at a viscosity between about 800 and 200,000 centipoise.
3. The system of claim 2 wherein the paste is maintained at the viscosity by applying heat to the paste at between about 150 and 200 degrees Fahrenheit.
4. The system of claim 1 wherein the chopped carbon fibers have lengths between about 12.5 and 75 millimeters.
5. The system of claim 1 wherein the carbon fibers have a size of between about 24,000 and 320,000 filaments.
6. The system of claim 1 wherein the paste includes about 35% weight of a resin system and about 65% weight of a filler system.
7. The system of claim 1 wherein the mechanism for compacting the carbon-filled laminate further wets-out the carbon-filled laminate.
8. The system of claim 1 wherein the compacted laminate is maintained at a predetermined temperature for a set time period, to mature the laminate for compression molding.
9. The system of claim 8 wherein the predetermined temperature is approximately 85 degrees Fahrenheit and the set time period is approximately between about 1 and 3 days.
10. The system of claim 1 further comprising coating substantially one side of the other of the first and second carrier films with the predetermined resin paste.