Composite material and method of producing the same, and composite metal material and method of producing the same

1. A method of producing a composite metal material, the method comprising:

(a) mixing at least a first carbon material and a particulate metal material Z into an elastomer, and dispersing the first carbon material and the metal material Z by applying a shear force to obtain a composite elastomer, the metal material Z having a melting point lower than a melting point of the first carbon material;

(b) heat-treating the composite elastomer in an atmosphere containing oxygen to vaporize the elastomer included in the composite elastomer to obtain an intermediate composite material including a second carbon material, wherein the second carbon material is derived from the first carbon material and the metal material Z;

(c) heat-treating the intermediate composite material together with a substance including an element Y having a melting point lower than the melting point of the metal material Z to vaporize the substance including the element Y;

(d) grinding a composite material obtained by the step (c) to powder, the composite material including a carbon-based material and the metal material Z; and

(e) powder forming the composite material to obtain the composite metal material,

wherein:

the metal material Z is aluminum or an alloy containing aluminum as a major component;

the element Y is magnesium;

the heat treatment temperature in the step (b) is set at a point lower than the vaporization temperature of the substance including the element Y;

the heat treatment temperature in the step (c) is set at a point higher than the heat treatment temperature in the step (b), the heat treatment temperature in the step (c) is set at a point equal to or higher than the vaporization temperature of the substance including the element Y, and the heat treatment temperature in the step (c) is set at a point lower than the vaporization temperatures of the metal material Z and the first carbon material;

a surface of the first carbon material activated in the step (a) bonds to oxygen present in the atmosphere inside a furnace by the heat treatment in the step (b) to obtain the second carbon material having a surface oxidized; and

the composite metal material has a compressive yield strength mean value of 320 MPa or more.

2. A method of producing a composite metal material, the method comprising:

(a) mixing at least a first carbon material and a particulate metal material Z into an elastomer, and dispersing the first carbon material and the metal material Z by applying a shear force to obtain a composite elastomer, the metal material Z having a melting point lower than a melting point of the first carbon material;

(b) heat-treating the composite elastomer in an atmosphere containing oxygen to vaporize the elastomer included in the composite elastomer to obtain an intermediate composite material including a second carbon material, wherein the second carbon material is derived from the first carbon material and the metal material Z;

(c) heat-treating the intermediate composite material together with a substance including an element Y having a melting point lower than the melting point of the metal material Z to vaporize the substance including the element Y;

(d) grinding a composite material obtained by the step (c) to powder, the composite material including a carbon-based material and the metal material Z; and

(e) causing a molten matrix metal material to permeate the composite material to obtain the composite metal material,

wherein:

the metal material Z is aluminum or an alloy containing aluminum as a major component;

the element Y is magnesium;

the heat treatment temperature in the step (b) is set at a point lower than the vaporization temperature of the substance including the element Y;

the heat treatment temperature in the step (c) is set at a point higher than the heat treatment temperature in the step (b), the heat treatment temperature in the step (c) is set at a point equal to or higher than the vaporization temperature of the substance including the element Y, and the heat treatment temperature in the step (c) is set at a point lower than the vaporization temperatures of the metal material Z and the first carbon material;

a surface of the first carbon material activated in the step (a) bonds to oxygen present in the atmosphere inside a furnace by the heat treatment in the step (b) to obtain the second carbon material having a surface oxidized;

a material for the matrix metal material is the same as a material for the metal material Z; and

the composite metal material has a compressive yield strength mean value of 320 MPa or more.

3. The method of producing a composite metal material as defined in claim 1 ,

wherein the step (b) is performed in the presence of a substance including an element X so that the element X bonds to a carbon atom of the first carbon material; and

wherein the element X includes at least one element selected from boron, nitrogen, oxygen, and phosphorus.

4. The method of producing a composite metal material as defined in claim 2 ,

wherein the step (b) is performed in the presence of a substance including an element X so that the element X bonds to a carbon atom of the first carbon material; and

wherein the element X includes at least one element selected from boron, nitrogen, oxygen, and phosphorus.

5. The method of producing a composite metal material as defined in claim 3 ,

wherein the composite elastomer includes the substance having the element X; and

wherein the element X bonds to a carbon atom of the first carbon material by the heat treatment in the step (b).

6. The method of producing a composite metal material as defined in claim 4 ,

wherein the composite elastomer includes the substance having the element X; and

wherein the element X bonds to a carbon atom of the first carbon material by the heat treatment in the step (b).

7. The method of producing a composite metal material as defined in claim 1 , wherein the substance including the element Y is mixed with the elastomer in the step (a).

8. The method of producing a composite metal material as defined in claim 2 , wherein the substance including the element Y is mixed with the elastomer in the step (a).

9. The method of producing a composite metal material as defined in claim 1 , wherein, in the step (c), the substance including the element Y is disposed in a heat treatment furnace together with the second carbon material and vaporized by the heat treatment.

10. The method of producing a composite metal material as defined in claim 2 , wherein, in the step (c), the substance including the element Y is disposed in a heat treatment furnace together with the second carbon material and vaporized by the heat treatment.

11. The method of producing a composite metal material as defined in claim 1 , wherein the first carbon material is carbon black.

12. The method of producing a composite metal material as defined in claim 2 , wherein the first carbon material is carbon black.

13. The method of producing a composite metal material as defined in claim 1 , wherein the first carbon material is carbon fiber.

14. The method of producing a composite metal material as defined in claim 2 , wherein the first carbon material is carbon fiber.

15. The method of producing a composite metal material as defined in claim 13 , wherein the carbon fiber is carbon nanofiber.

16. The method of producing a composite metal material as defined in claim 14 , wherein the carbon fiber is carbon nanofiber.

17. The method of producing a composite metal material as defined in claim 15 , wherein the carbon nanofibers have an average diameter of 0.5 to 500 nm.

18. The method of producing a composite metal material as defined in claim 16 , wherein the carbon nanofibers have an average diameter of 0.5 to 500 nm.

19. The method of producing a composite metal material as defined in claim 1 , wherein the elastomer has a molecular weight of 5,000 to 5,000,000.

20. The method of producing a composite metal material as defined in claim 2 , wherein the elastomer has a molecular weight of 5,000 to 5,000,000.

21. The method of producing a composite metal material as defined in claim 1 , wherein at least one of a main chain, a side chain, and a terminal chain of the elastomer includes at least one unsaturated bond or group having affinity to carbon nanofibers selected from the group consisting of a double bond, a triple bond, α-hydrogen, a carbonyl group, a carboxyl group, a hydroxyl group, an amino group, a nitrile group, a ketone group, an amide group, an epoxy group, an ester group, a vinyl group, a halogen group, a urethane group, a biuret group, an allophanate group, and a urea group.

22. The method of producing a composite metal material as defined in claim 2 , wherein at least one of a main chain, a side chain, and a terminal chain of the elastomer includes at least one unsaturated bond or group having affinity to carbon nanofibers selected from the group consisting of a double bond, a triple bond, α-hydrogen, a carbonyl group, a carboxyl group, a hydroxyl group, an amino group, a nitrite group, a ketone group, an amide group, an epoxy group, an ester group, a vinyl group, a halogen group, a urethane group, a biuret group, an allophanate group, and a urea group.

23. The method of producing a composite metal material as defined in claim 1 , wherein a network component of the elastomer in an uncrosslinked form has a spin-spin relaxation time (T 2 n ) of 100 to 3,000 μsec, measured at 30° C. by a Hahn-echo method using a pulsed nuclear magnetic resonance (NMR) technique.

24. The method of producing a composite metal material as defined in claim 2 , wherein a network component of the elastomer in an uncrosslinked form has a spin-spin relaxation time (T 2 n ) of 100 to 3,000 μsec, measured at 30° C. by a Hahn-echo method using a pulsed nuclear magnetic resonance (NMR) technique.

25. The method of producing a composite metal material as defined in claim 1 , wherein a network component of the elastomer in a crosslinked form has a spin-spin relaxation time (T 2 n ) of 100 to 2,000 μsec, measured at 30° C. by a Hahn-echo method using a pulsed nuclear magnetic resonance (NMR) technique.

26. The method of producing a composite metal material as defined in claim 2 , wherein a network component of the elastomer in a crosslinked form has a spin-spin relaxation time (T 2 n ) of 100 to 2,000 μsec, measured at 30° C. by a Hahn-echo method using a pulsed nuclear magnetic resonance (NMR) technique.

27. The method of producing a composite metal material as defined in claim 1 , wherein the elastomer is natural rubber or nitrile butadiene rubber.

28. The method of producing a composite metal material as defined in claim 2 , wherein the elastomer is natural rubber or nitrile butadiene rubber.

29. The method of producing a composite metal material as defined in claim 1 , wherein the step (a) is performed by using an open roll method with a roll interval of 0.5 mm or less.

30. The method of producing a composite metal material as defined in claim 2 , wherein the step (a) is performed by using an open roll method with a roll interval of 0.5 mm or less.

31. The method of producing a composite metal material as defined in claim 29 , wherein two rolls used in the open-roll method have a surface velocity ratio of 1.05 to 3.00.

32. The method of producing a composite metal material as defined in claim 30 , wherein two rolls used in the open-roll method have a surface velocity ratio of 1.05 to 3.00.

33. The method of producing a composite metal material as defined in claim 1 , wherein the step (a) is performed by using an internal mixing method.

34. The method of producing a composite metal material as defined in claim 2 , wherein the step (a) is performed by using an internal mixing method.

35. The method of producing a composite metal material as defined in claim 1 , wherein the step (a) is performed by using a multi-screw extrusion kneading method.

36. The method of producing a composite metal material as defined in claim 2 , wherein the step (a) is performed by using a multi-screw extrusion kneading method.

37. The method of producing a composite metal material as defined in claim 1 , wherein the step (a) is performed at 0 to 50° C.

38. The method of producing a composite metal material as defined in claim 2 , wherein the step (a) is performed at 0 to 50° C.