METHOD FOR MANUFACTURING COMPOSITE MATERIAL, AND COMPOSITE MATERIAL

Abstract

Methods for manufacturing a composite material and composite materials are provided. The method may include preparing a metal foam, preparing a mixture including the metal foam and a curable polymer, curing the curable polymer of the mixture to obtain a composite material, and performing a planarization treatment. The planarization treatment may be performed on the metal foam before preparing the mixture, on the mixture before curing the curable polymer, and/or on the composite material. The composite materials may include a metal foam and a polymer that is on a surface and/or in pores of the metal foam. The composite material may have a surface roughness of 2 μm or less and/or may have a thermal resistance of 0.5 Kin.sup.2/W or less at 20 psi.

Claims

1. A method for manufacturing a composite material, the method comprising steps of: (a) providing a metal foam; (b) preparing a mixture comprising the metal foam and a curable polymer; (c) curing the curable polymer of the mixture to obtain the composite material; and (d) performing a planarization treatment on at least one of the metal foam before preparing the mixture, the mixture before curing the curable polymer, and the composite material.

2. The method for manufacturing the composite material according to claim 1, wherein the step (d) is performed on the metal foam before the step (b).

3. The method for manufacturing the composite material according to claim 2, wherein after the step (d) is performed, a porosity of the metal foam is in a range of 30% to 60%.

4. The method for manufacturing the composite material according to claim 2, wherein after the step (d) is performed, a surface roughness of the metal foam is 6 μm or less.

5. The method for manufacturing the composite material according to claim 1, wherein the step (d) is performed by polishing or pressing.

6. The method for manufacturing the composite material according to claim 5, wherein the pressing is performed by a roll press.

7. The method for manufacturing the composite material according to claim 1, wherein the step (a) is performed in a manner comprising (a1) a process of manufacturing a green structure using a slurry comprising a metal powder, a binder and a dispersant, and (a2) a process of sintering the green structure.

8. A composite material comprising: a metal foam comprising a plurality of pores; and a polymer on a surface and/or in the plurality of pores of the metal foam, wherein the composite material has a surface roughness of 2 μm or less and has a thermal resistance of 0.5 Kin.sup.2/W or less at 20 psi.

9. The composite material according to claim 8, wherein the metal foam has a porosity in a range of 30% to 60%.

10. The composite material according to claim 9, wherein the metal foam has a porosity in the range of 40% to 50%.

11. The composite material according to claim 8, wherein the metal foam is in the form of a film or sheet.

12. The composite material according to claim 11, wherein the metal foam in the form of a film or sheet has a thickness of 2,000 μm or less.

13. The method for manufacturing the composite material according to claim 2, wherein a ratio (TA/TB) of a first thickness (TA) of the metal foam after performing the planarization treatment to a second thickness (TB) of the metal foam before performing the planarization treatment is 0.9 or less.

14. The method for manufacturing the composite material according to claim 2, wherein a ratio (RA/RB) of a first surface roughness (RA) of the metal foam after performing the planarization treatment to a second surface roughness (RB) of the metal foam before performing the planarization treatment is 0.9 or less.

15. The method for manufacturing the composite material according to claim 2, wherein a ratio (KA/KB) of a first thermal resistance (KA) of the metal foam after performing the planarization treatment to a second thermal resistance (KB) of the metal foam before performing the planarization treatment is 0.9 or less.

Description

DESCRIPTION OF DRAWINGS

[0096] FIG. 1 is a laser micrograph of the metal foam of Manufacturing Example 1 and a surface shape analysis result thereof.

[0097] FIG. 2 is an SEM photograph of the metal foam of Manufacturing Example 2.

[0098] FIG. 3 is a laser micrograph of the metal foam of Manufacturing Example 5 and a surface shape analysis result thereof.

[0099] FIG. 4 is an SEM photograph of the metal foam of Manufacturing Example 6.

[0100] FIG. 5 is a laser micrograph of the composite material of Example 1 and a surface shape analysis result thereof.

[0101] FIG. 6 is an SEM photograph of the composite material of Example 1.

[0102] FIG. 7 is an SEM photograph of the composite material of Example 2.

[0103] FIG. 8 is an SEM photograph of the composite material of Comparative Example 1.

[0104] FIG. 9 is a SEM photograph of the composite material of Comparative Example 2.

BEST MODE

[0105] Hereinafter, the present application will be described in detail through the following examples, but the scope of the present application is not limited by the following examples.

Manufacturing Example 1. Metal Foam

[0106] Copper (Cu) powder having an average particle diameter (D50 particle diameter) of about 60 μm or so was used. Texanol was used as a dispersant, and ethyl celluose was used as a binder. A slurry was prepared by mixing a solution obtained by dissolving ethyl cellulose in texanol to be a concentration of about 7 weight % with the copper power so that the weight ratio was about 1:1.

[0107] The slurry was coated in the form of a film having a thickness of about 250 μm, and dried at a temperature of about 120° C. for about 60 minutes to form a metal foam precursor. Thereafter, sintering was performed by applying an external heat source in an electric furnace so as to maintain the precursor at a temperature of about 1000° C. for about 2 hours in a hydrogen/argon atmosphere, and a metal foam was manufactured. The manufactured metal foam had a thickness of about 85 μm, a porosity of about 64%, surface roughness of about 7.5 μm or so, and thermal resistance of about 0.466 Kin.sup.2/W under a pressure condition of 20 psi. Analysis Tech's TIM Tester 1300 was used as the measuring equipment for thermal resistance, and it was measured according to the manual of the equipment (hereinafter, this was used in the same manner).

[0108] A laser micrograph of the metal foam of Manufacturing Example 1 and a surface shape analysis result thereof were shown in FIG. 1.

Manufacturing Example 2. Metal Foam

[0109] A metal foam was manufactured in the same manner as in Manufacturing Example 1, except that the slurry coating thickness was adjusted to about 300 μm. The manufactured metal foam had a thickness of about 100 μm, a porosity of about 64%, surface roughness of about 8 μm or so, and thermal resistance of about 0.496 Kin.sup.2/W under a pressure condition of 20 psi. The SEM photograph of the metal foam was shown in FIG. 2.

Manufacturing Example 3. Metal Foam

[0110] A metal foam was manufactured in the same manner as in Manufacturing Example 1, except that the slurry coating thickness was adjusted to about 1500 μm. The manufactured metal foam had a thickness of about 500 μm, a porosity of about 70%, surface roughness of about 9 μm or so, and thermal resistance of about 0.871 Kin.sup.2/W under a pressure condition of 20 psi.

Manufacturing Example 4. Metal Foam

[0111] A metal foam was manufactured in the same manner as in Manufacturing Example 1, except that the slurry coating thickness was adjusted to about 2500 μm. The manufactured metal foam had a thickness of about 1000 μm, a porosity of about 75%, surface roughness of about 10 μm or so, and thermal resistance of about 1.064 Kin.sup.2/W under a pressure condition of 20 psi.

Manufacturing Example 5. Metal Foam

[0112] A gap between rolls of a roll press device (WCRP-1015G, Wellcos Corp) was set to 70 μm, and the metal foam of Manufacturing Example 1 was passed through the rolls of the device to manufacture a pressed metal foam. The pressed metal foam had a thickness of about 70 μm, a porosity of about 53%, surface roughness of about 5.2 μm or so, and thermal resistance of about 0.335 Kin.sup.2/W under a pressure condition of 20 psi. A laser micrograph of the metal foam of Manufacturing Example 5 and a surface shape analysis result thereof were shown in FIG. 3.

Manufacturing Example 6. Metal Foam

[0113] A gap between rolls of a roll press device (WCRP-1015G, Wellcos Corp) was set to 80 μm, and the metal foam of Manufacturing Example 2 was passed through the rolls of the device to manufacture a pressed metal foam. The pressed metal foam had a thickness of about 80 μm, a porosity of about 57%, surface roughness of about 4 μm or so, and thermal resistance of about 0.360 Kin.sup.2/W under a pressure condition of 20 psi. An SEM photograph of Manufacturing Example 6 was shown in FIG. 4.

Manufacturing Example 7. Metal Foam

[0114] A gap between rolls of a roll press device (WCRP-1015G, Wellcos Corp) was set to 300 μm, and the metal foam of Manufacturing Example 3 was passed through the rolls of the device to manufacture a pressed metal foam. The pressed metal foam had a thickness of about 300 μm, a porosity of about 55%, surface roughness of about 5 μm or so, and thermal resistance of about 0.403 Kin.sup.2/W under a pressure condition of 20 psi.

Manufacturing Example 8. Metal Foam

[0115] C6—A gap between rolls of a roll press device (WCRP-1015G, Wellcos Corp) was set to 500 μm, and the metal foam of Manufacturing Example 4 was passed through the rolls of the device to manufacture a pressed metal foam. The pressed metal foam had a thickness of about 50 μm, a porosity of about 45%, surface roughness of about 4 μm or so, and thermal resistance of about 0.527 Kin.sup.2/W under a pressure condition of 20 psi.

[0116] According to FIGS. 1 to 4, it can be confirmed that the metal foam surface is formed relatively smoothly pursuant to pressing, thereby having lower thermal resistance than that before pressing.

Example 1. Composite Material

[0117] The metal foam of Manufacturing Example 5 was immersed in a thermosetting silicone resin (polydimethylsiloxane, Sylgard 527 kit, Dow Corning) as a curable polymer. The excess amount of the silicone resin was removed using a film applicator so that the thickness of the curable polymer composition in which the metal foam was immersed was about 80 μm. Subsequently, the polymer composition was cured by holding it in an oven maintained at 120° C. for about 10 minutes to manufacture a film-shaped composite material. FIG. 5 is a laser micrograph of the composite material of Example 1 and a surface shape analysis result thereof, and FIG. 6 is an SEM photograph of the composite material of Example 1. The surface roughness of the composite material was about 1.2 μm, and the thermal resistance was about 0.098 Kin.sup.2/W under a pressure condition of 20 psi.

Example 2. Composite Material

[0118] A composite material was manufactured in the same manner as in Example 1, except that the metal foam of Manufacturing Example 6 was immersed instead of the metal foam of Manufacturing Example 5, and the excess amount of the silicone resin was removed using a film applicator so that the thickness of the curable polymer composition in which the metal foam was immersed was about 90 μm. FIG. 7 is an SEM photograph of the composite material of Example 2. The surface roughness of the composite material was about 1.5 μm, and the thermal resistance was about 0.102 Kin.sup.2/W under a pressure condition of 20 psi.

Example 3. Composite Material

[0119] A composite material was manufactured in the same manner as in Example 1, except that the metal foam of Manufacturing Example 7 was immersed instead of the metal foam of Manufacturing Example 5, and the excess amount of the silicone resin was removed using a film applicator so that the thickness of the curable polymer composition in which the metal foam was immersed was about 320 μm. The surface roughness of the composite material was about 1.6 μm, and the thermal resistance was about 0.226 Kin.sup.2/W under a pressure condition of 20 psi.

Example 4. Composite Material

[0120] A composite material was manufactured in the same manner as in Example 1, except that the metal foam of Manufacturing Example 8 was immersed instead of the metal foam of Manufacturing Example 5, and the excess amount of the silicone resin was removed using a film applicator so that the thickness of the curable polymer composition in which the metal foam was immersed was about 525 μm. The surface roughness of the composite material was about 1.8 μm, and the thermal resistance was about 0.315 Kin.sup.2/W under a pressure condition of 20 psi.

Comparative Example 1. Composite Material

[0121] A composite material was manufactured in the same manner as in Example 1, except that the metal foam of Manufacturing Example 1 was immersed instead of the metal foam of Manufacturing Example 5, and the excess amount of the silicone resin was removed using a film applicator so that the thickness of the curable polymer composition in which the metal foam was immersed was about 100 μm. FIG. 8 is an SEM photograph of the composite material of Comparative Example 1. The surface roughness of the composite material was about 2.5 μm, and the thermal resistance was about 0.203 Kin.sup.2/W under a pressure condition of 20 psi.

Comparative Example 2. Composite Material

[0122] A composite material was manufactured in the same manner as in Example 1, except that the metal foam of Manufacturing Example 2 was immersed instead of the metal foam of Manufacturing Example 5, and the excess amount of the silicone resin was removed using a film applicator so that the thickness of the curable polymer composition in which the metal foam was immersed was about 110 μm. FIG. 9 is an SEM photograph of the composite material of Comparative Example 2. The surface roughness of the composite material was about 2.4 μm, and the thermal resistance was about 0.236 Kin.sup.2/W under a pressure condition of 20 psi.

Comparative Example 3. Composite Material

[0123] A composite material was manufactured in the same manner as in Example 1, except that the metal foam of Manufacturing Example 3 was immersed instead of the metal foam of Manufacturing Example 5, and the excess amount of the silicone resin was removed using a film applicator so that the thickness of the curable polymer composition in which the metal foam was immersed was about 530 μm. The surface roughness of the composite material was about 3.2 μm, and the thermal resistance was about 0.652 Kin.sup.2/W under a pressure condition of 20 psi.

Comparative Example 4. Composite Material

[0124] A composite material was manufactured in the same manner as in Example 1, except that the metal foam of Manufacturing Example 4 was immersed instead of the metal foam of Manufacturing Example 5, and the excess amount of the silicone resin was removed using a film applicator so that the thickness of the curable polymer composition in which the metal foam was immersed was about 1050 μm. The surface roughness of the composite material was about 3.0 μm, and the thermal resistance was about 0.783 Kin.sup.2/W under a pressure condition of 20 psi.

[0125] The physical property analysis results of the composite materials of Examples and Comparative Examples were shown in Tables 1 and 2 below.

TABLE-US-00001 TABLE 1 Example 1 2 3 4 Applied metal Manufac- Manufac- Manufac- Manufac- foam turing turing turing turing Example 5 Example 6 Example 7 Example 8 Surface roughness 1.2 1.5 1.6 1.8 Thermal resistance 0.098 0.102 0.226 0.315 @20 psi(Kin.sup.2/W)

TABLE-US-00002 TABLE 2 Comparative Example 1 2 3 4 Applied metal Manufac- Manufac- Manufac- Manufac- foam turing turing turing turing Example 1 Example 2 Example 3 Example 4 Surface roughness 2.5 2.4 3.2 3.0 Thermal resistance 0.203 0.236 0.652 0.783 @20 psi (Kin.sup.2/W)

[0126] According to Tables 1 and 2, it can be confirmed that the composite materials manufactured through the planarization treatment, specifically the composite materials of Examples 1 to 4 manufactured using the pressed metal foams have the lower surface roughness relative to the thickness than that of the composite materials of Comparative Examples and have reduced thermal resistance. Through this, it can be seen that when a composite material is manufactured with a planarization treatment as in the method of the present application, the surface roughness and thermal conductivity of the composite material can be improved.