COMPOSITE MATERIAL

Abstract

The present application provides a composite material and a method for producing the same. The present application can provide a composite material which comprises a metal foam and a polymer component, and has other excellent physical properties such as impact resistance, processability and insulation properties while having excellent thermal conductivity.

Claims

1. A composite material, comprising: a metal foam comprising pores; a metal oxide contacting a surface of the metal foam; and a polymer component on the surface of the metal foam or in the pores of the metal foam, wherein the composite material has a thermal conductivity of 0.4 W/mK or more.

2. The composite material according to claim 1, wherein the metal oxide comprises protrusions.

3. The composite material according to claim 2, wherein an aspect ratio of the protrusions is in a range of 1 to 8.

4. The composite material according to claim 1, wherein the metal oxide covers 5% to 60% of the surface of the metal foam.

5. The composite material according to claim 1, wherein a ratio (T/MT) of a total thickness (T) of the composite material to a thickness (MT) of the metal foam is 2.5 or less.

6. The composite material according to claim 1, wherein a ratio (MV/PV) of a volume (MV) of the metal foam to a volume (PV) of the polymer component is 10 or less.

7. A method of producing a composite material, the method comprising: forming a porous metal body by sintering a metal structure comprising a metal component; forming a metal oxide on a surface of the porous metal body by contacting the porous metal body with oxygen, and then applying a polymer component to the porous metal body.

8. The method according to claim 7, further comprising forming the metal structure using a slurry including the metal component, a dispersant and a binder.

9. The method according to claim 8, wherein the dispersant is an alcohol.

10. The method according to claim 8, wherein the binder is an alkylcellulose, a polyalkylene carbonate or a polyvinyl alcohol.

11. The method according to claim 8, wherein the slurry comprises 1 to 500 parts by weight of the binder relative to 100 parts by weight of the metal component.

12. The method according to claim 8, wherein the slurry comprises 10 to 2,000 parts by weight of the dispersant relative to 100 parts by weight of the binder.

13. The method according to claim 7, wherein contacting the porous metal body with oxygen is performed at a temperature in a range of 300° C. to 600° C.

14. The method according to claim 13 further comprising naturally cooling the porous metal body after sintering the metal structure, wherein contacting the porous metal body with oxygen is performed when the temperature is in the range of 300° C. to 600° C. while naturally cooling the porous metal body.

15. The method according to claim 13, wherein contacting the porous metal body with oxygen is performed under an oxygen concentration of 1 ppm to 10,000 ppm.

16. The method according to claim 7, further comprising naturally cooling the porous metal body, wherein naturally cooling the porous metal body and contacting the porous metal body with oxygen are performed simultaneously.

17. The method according to claim 16, wherein contacting the porous metal body with oxygen comprising injecting a gas having an oxygen concentration in a range of about 400 ppm to 700 ppm at an ambient temperature of about 500° C.

18. The method according to claim 7, wherein sintering the metal structure is performed in a hydrogen/argon atmosphere.

19. The method according to claim 7, wherein the metal oxide comprises protrusions.

20. The composite material according to claim 1, wherein the polymer component includes an acrylic resin, a silicone resin, an epoxy resin, a urethane resin, an amino resin, or a phenol resin.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0100] FIG. 1 is a photograph of a metal foam formed in an example.

MODE FOR INVENTION

[0101] Hereinafter, the present application will be described in detail by way of examples and comparative examples, but the scope of the present application is not limited to the following examples.

Example 1

[0102] The metal foam was a copper metal foam, where the copper metal foam in a film shape, in which the oxide in the form of protrusions is present on the surface, having a thickness of about 90 μm or so and a porosity of about 65% to 75% was used. The copper foam was prepared with a slurry using a copper (Cu) powder with an average particle diameter (D50 particle diameter) of about 10 to 20 μm or so as a metal component, using alpha-terpineol as a dispersant and applying polyvinyl acetate as a binder. The weight ratio (Cu:dispersant:binder) of the metal component (Cu), the dispersant and the binder in the slurry was about 1:1.11:0.09 or so. The slurry was coated so as to form the film of the above thickness and dried at a temperature of about 100° C. for about 40 minutes. Subsequently, the structure in the form of a film was heat-treated (sintered) at a temperature of about 900° C. for about 1 hour in a hydrogen/argon gas atmosphere of 4%, and the metal component was bonded while removing the organic components to prepare a porous metal sintered body. After the sintering, the sintered body was naturally cooled and simultaneously brought into contact with oxygen by injecting oxygen gas to have a concentration in a range of about 400 ppm to 700 ppm at an ambient temperature of about 500° C. or so until the ambient temperature become room temperature (about 25° C.). FIG. 1 is a photograph of the sheet prepared in Example 1, and it can be confirmed from the photograph that the oxide in the form of protrusions is grown on the surface of the metal foam. The aspect ratio of the protrusion shape was in the range of about 1 to 3, and the area ratio of the oxide was about 10% to 30% or so. The copper foam was impregnated with a thermosetting silicone resin composition (Dow Corning, PDMS, Sylgard 183 Kit), and an excess amount of the composition was removed using an applicator so that the final composite material had a thickness of about 110 μm or so. Subsequently, the material was maintained in an oven at about 120° C. for about 10 minutes or so and cured to prepare a composite material. As a result of being calculated based on the density and the applied weight of each of the applied polymer component (silicone resin) and metal foam (copper foam), the ratio (MV/PV) of the volume (MV) of the metal foam to the volume (PV) of the polymer component was about 0.3 or so. The thermal conductivity of this composite material was about 5.12 W/mK or so.

[0103] The thermal conductivity was determined by obtaining the thermal diffusivity (A), specific heat (B) and density (C) of the composite material and substituting them into an equation of thermal conductivity=ABC, where the thermal diffusivity was measured with a laser flash method (LFA equipment, model name: LFA467), the specific heat was measured by way of DSC (differential scanning calorimeter) equipment and the density was measured with Archimedes method. Also, the thermal conductivity is a value with respect to the thickness direction (Z axis) of the composite material.

Example 2

[0104] A composite material was prepared in the same manner as in Example 1, except that a different kind of composition (Dow Corning, PDMS, Sylgard 527 Kit) was used as the thermosetting silicone resin composition. As a result of measuring the thermal conductivity of the prepared composite material in the above-mentioned manner, it was about 6.86 W/mK or so.

Example 3

[0105] A composite material was prepared in the same manner as in Example 2, except that a plate-like boron nitride powder was introduced into a thermosetting silicone resin composition (Dow Corning, PDMS, Sylgard 527 Kit) at a ratio of about 10 wt % or so and used. As a result of measuring the thermal conductivity of the prepared composite material in the above-mentioned manner, it was about 10.14 W/mK or so.