Method of making carbonized composites
Methods of producing a fiber reinforced polymer matrix composite and a composite thermal protection system formed from the same. The method includes forming a polymerized fiber reinforced composite which including a cured thermoset polymer matrix and at least one reinforcement material. The method further includes treating at least a portion of a first face of the polymerized fiber reinforced composite with electromagnetic radiation to raise the temperature of the portion of the first face to at least 800° C. to produce a surface layer of graphitized carbon and a bulk polymerized fiber reinforced composite representing the untreated polymerized fiber reinforced composite. Further, the surface layer of graphitized carbon has an electrical conductivity of 0.25 S m −1 to 2.5 S m −1 where the electrical conductivity and a thermal conductivity are both greater than those of the bulk polymerized reinforced composite.
1. A composite thermal protection system (TPS), the composite TPS comprising:
a surface layer of graphitized carbon formed from treating at least a portion of a first face of a polymerized fiber reinforced composite comprising a cured thermoset polymer matrix and at least one reinforcement material with electromagnetic radiation to raise the temperature of the portion of the first face to at least 800° C.,
wherein a thermoset polymer forming the cured thermoset polymer matrix comprises polymer represented by chemical formula (I) or (II) or (III)
wherein:
m and n are each an integer greater than or equal to 1,
at least one of R 1 or R 2 comprises an aromatic moiety, and
X is selected from the group consisting of CH 2 , NH, O, S, SO 2 , and combinations thereof;
wherein formation of the surface layer of graphitized carbon directly from the polymerized fiber reinforced composite results in the surface layer of graphitized carbon being unified with a bulk polymerized fiber reinforced composite representing the polymerized fiber reinforced composite not treated with the electromagnetic radiation;
wherein the surface layer of graphitized carbon comprises an electrical conductivity of 0.25 S m −1 to 2.5 S m −1 ; and
wherein the surface layer of graphitized carbon comprises a thermal conductivity that is greater than a thermal conductivity of the bulk polymerized reinforced composite.
2. The composite TPS of claim 1 , wherein the reinforcement material is carbon fiber or ceramic fiber.
3. The composite TPS of claim 1 , wherein a thickness of the surface layer of graphitized carbon ranges from 0.05 to 2 mm.
4. The composite TPS of claim 1 , wherein the thermal conductivity of the surface layer of graphitized carbon ranges from 10 to 4000 W m −1 K −1 .
5. The composite TPS of claim 1 , wherein the surface layer of graphitized carbon extends across at least 90% of the first face of the polymerized fiber reinforced composite.
6. The composite TPS of claim 1 , wherein electrically and thermally conductive traces in a defined pattern form the surface layer of graphitized carbon.
7. The composite TPS of claim 6 , wherein the electrically and thermally conductive traces cover less than 50% of the area of the first face of the polymerized fiber reinforced composite.
8. The composite TPS of claim 1 , wherein the electromagnetic radiation is applied at a power density of 0.05 W/mm 2 to 0.75 W/mm 2 and deliver a total energy density to the portion of the first face of 0.5 J/mm 2 to 2.5 J/mm 2 .
9. The composite TPS of claim 1 , wherein the composite thermal protection system is applied to a hypersonic vehicle.
10. The composite TPS of claim 1 , wherein the composite thermal protection system is in a lightning strike protection, radar absorbing, deicing, or EMI shielding application.
11. A composite thermal protection system (TPS), the composite TPS comprising:
a bulk polymerized fiber reinforced composite comprising:
a cured thermoset polymer matrix; and
at least one reinforcement material; and
a surface layer of graphitized carbon unified with the bulk polymerized fiber reinforced composite;
wherein a thermoset polymer forming the cured thermoset polymer matrix comprises comprises polymer represented by chemical formula (D) or (II) or (IID)
wherein;
m and n are each an integer greater than or equal to 1,
at least one of R 1 or R 2 comprises an aromatic moiety, and
X is selected from the group consisting of CH 2 , NH, O, S, SO 2 , and combinations thereof;
wherein the bulk polymerized fiber reinforced composite and the surface layer of graphitized carbon form a monolith without an adhesive or fastener to secure the surface layer of graphitized carbon to the bulk polymerized fiber reinforced composite;
wherein the surface layer of graphitized carbon comprises an electrical conductivity of 0.25 S m −1 to 2.5 S m −1 ; and
wherein the surface layer of graphitized carbon comprises a thermal conductivity that is greater than a thermal conductivity of the bulk polymerized reinforced composite.