Metal separation plate and method for manufacturing the same

Abstract

This application relates to a metal separation plate and a method for manufacturing the same, comprising a first base material including a first manifold section, a second manifold section, and a reaction section provided between the first and second manifold sections, wherein the first and second manifold sections each comprise a plurality of openings and a surface layer located between the plurality of openings, and a surface modification layer is formed on the upper surface of the surface layer and the inner surface of the openings, respectively, wherein the metal separation plate and its manufacturing method not only have excellent electrical conductivity but also excellent corrosion resistance.

Claims

1. The first base material includes a first manifold section, a second manifold section, and a reaction section provided between the first manifold section and the second manifold section. The first manifold section and the second manifold section each comprise a plurality of openings and a surface layer located between the plurality of openings. A metal separation plate having a surface modification layer formed on the upper surface of the surface layer and on the inner surface of the opening, respectively.

2. The metal separation plate according to claim 1, wherein the first base material comprises 28,000% to 33,000% by weight of chromium, 0.010% by weight or less of carbon, 0.200% by weight or less of silicon, 0.300% by weight or less of manganese, 0.300% by weight or less of titanium, the remainder being iron and other unavoidable impurities.

3. The metal separation plate according to claim 1, wherein the surface modification layer formed on the upper surface of the surface layer contains 20 at% to 28 at% chromium in the region from the surface exposed to the outside to a depth of 1.0 nm, and contains 15 at% to 25 at% iron in the region from the surface exposed to the outside to a depth of 1.0 nm.

4. The metal separation plate according to claim 1, wherein the surface modification layer formed on the upper surface of the surface layer and the inner surface of the opening portion, respectively, is heat-treated at 100°C to 300°C for 10 to 300 seconds.

5. The first base material has a contact resistance of 14 mΩ·cm under a contact pressure of 1.0 MPa. ２ The following is true: 0.6V ｖｓ ＳＣＥ At a potential of 4 μA / cm², the current density is 4 μA / cm². ２ The metal separation plate according to claim 1, which is as follows:

6. The metal separation plate according to claim 1, further comprising a porous body laminated on the upper surface of the reaction section.

7. A fuel cell cell comprising a metal separation plate according to any one of claims 1 to 6.

8. Preparation step to prepare the first base material; A manifold piercing step in which the first base material is punched out on both sides of one surface of the first base material to form a first manifold section and a second manifold section, each having a plurality of openings and a surface layer between the plurality of openings; A surface modification layer formation step of modifying the surface of the first base material on which the first manifold portion and the second manifold portion are formed, and forming a surface modification layer on the exposed surface of the first base material; and, The heat treatment step includes heat treatment of the first base material on which the surface modified layer is formed, A method for manufacturing a metal separation plate, wherein a surface modification layer is formed on the upper surface of the surface layer and the inner surface of the opening portion provided in the first manifold portion and the second manifold portion, respectively.

9. The method for manufacturing a metal separation plate according to claim 8, wherein the first base material comprises 28,000% to 33,000% by weight of chromium, 0.010% by weight or less of carbon, 0.200% by weight or less of silicon, 0.300% by weight or less of manganese, 0.300% by weight or less of titanium, the remaining iron and other unavoidable impurities.

10. The surface modification layer formation step includes a first modification step in which a solution is prepared by adding one or more selected from fluorine, hydrochloric acid, and phosphoric acid to a sulfuric acid solution, and the surface of the first base material is deposited in the solution; and, A method for manufacturing a metal separation plate according to claim 8, comprising a second modification step of depositing the first base material that has undergone the first modification step into a solution containing hydrogen peroxide and fluorine.

11. The method for manufacturing a metal separation plate according to claim 8, wherein the heat treatment step is performed at 100°C to 300°C for 10 to 300 seconds.

12. In the preparation step described above, prepare the second base material. The method for manufacturing a metal separation plate according to claim 8, further comprising a porous body piercing step of punching out the prepared second base material to form a porous body having a plurality of holes.

13. A method for manufacturing a metal separation plate according to claim 12, further comprising a laminate formation step of stacking and joining the porous material in the center of the first base material after performing the heat treatment step and the porous material piercing step to form a laminate.

14. The surface modification layer formation step further includes modifying the surface exposed to the outside of the second base material or porous body before or after the porous body piercing step, and forming a surface modification layer on the exposed surface of the second base material or porous body. The method for manufacturing a metal separation plate according to claim 12, wherein the heat treatment step further comprises heat treatment of a second base material or porous body on which the surface modification layer is formed.

15. The method for manufacturing a metal separation plate according to claim 12, further comprising a slitting step of slitting the widths of the first base material and the second base material, respectively, before performing the manifold piercing step and the porous body piercing step.

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