CN-121986002-A - Method for producing titanium molded body, method for producing titanium porous body, and titanium porous body

Abstract

The method for producing a titanium molded body according to the present invention is a method for producing a sheet-like titanium molded body, and comprises a joining step of drying a paste containing titanium powder, an organic binder and an organic solvent to laminate a plurality of sheet-like dried bodies each obtained, and heating the laminate to a temperature of 70 ℃ to 200 ℃ while pressurizing the laminate in the thickness direction with a pressure of 0.1N/cm 2 or more.

Inventors

• GAO TIANGUI
• INOUE YOUSUKE
• NAGANUMA NORIYUKI

Assignees

• 东邦钛株式会社

Dates

Publication Date

20260505

Application Date

20240829

Priority Date

20231215

Claims (14)

1. 1. A method for producing a titanium molded body in the form of a sheet, The method for producing a titanium molded body comprises a bonding step in which a paste containing titanium powder, an organic binder and an organic solvent is dried, and a plurality of sheet-like dried bodies obtained by the bonding step are stacked together and heated to a temperature of 70 ℃ to 200 ℃ while being pressurized at a pressure of 0.1N/cm 2 or more in the thickness direction.
2. 2. The method for producing a titanium molded article according to claim 1, wherein, The joining step is preceded by a drying step of drying the paste to obtain a sheet-like dried body.
3. 3. The method for producing a titanium molded article according to claim 2, wherein, In the drying step, the paste is heated to a temperature of 90 ℃ to 165 ℃.
4. 4. The method for producing a titanium molded body according to claim 2 or 3, wherein, Drying the paste in the drying step is performed on a resin substrate.
5. 5. The method for producing a titanium molded article according to any one of claim 1 to 4, wherein, In the joining step, the sheet-like dried bodies are pressed and heated in a state in which the plurality of laminated sheet-like dried bodies are sandwiched by molding dies from both sides in the thickness direction.
6. 6. The method for producing a titanium molded article according to claim 5, wherein, In the joining step, the resin base material is pressurized and heated while being sandwiched between the sheet-like dry body and the molding die.
7. 7. The method for producing a titanium molded article according to any one of claims 1 to 6, wherein, The average particle diameter of the titanium powder in at least one sheet of the sheet-like dried body is 10 [ mu ] m or more and 20 [ mu ] m or less.
8. 8. The method for producing a titanium molded article according to any one of claims 1 to 7, wherein, In the sheet-like dried body, the difference between the average particle diameter of the titanium powder in one of the sheet-like dried bodies on the front side and the average particle diameter of the titanium powder in at least one other sheet-like dried body is 5 [ mu ] m or more.
9. 9. The method for producing a titanium molded article according to any one of claims 1 to 8, wherein, The paste used to make the sheet-like dried body is free of foaming agents.
10. 10. A method for producing a titanium porous body, which is a method for producing a sheet-like titanium porous body, comprising: A binder removal step of heating the titanium molded body produced by the method for producing a titanium molded body according to any one of claims 1 to 9 to volatilize the organic binder in the titanium molded body, and And a sintering step of heating the titanium molded body after the binder removal step to sinter the titanium powder in the titanium molded body.
11. 11. A titanium porous body is a sheet-like titanium porous body, The titanium porous body comprises a plurality of titanium porous layers, wherein the titanium porous layers are laminated by mutually bonding adjacent titanium bonding surfaces in the thickness direction, each porous layer has a hole part, can transmit gas and/or liquid, In the porous layers, the average value of the areas of the holes opened on the surface of the porous layer forming one surface is 5 μm to 2 μm 2 , the standard deviation value of the areas of the holes is 35 μm to 2 , the number of the holes existing in the rectangular area with the area of 22000 μm 2 and the aspect ratio of 4:3 is 256 or more, The porosity of the porous layer including a plurality of layers is 40% to 60%.
12. 12. The titanium porous body according to claim 11, wherein, The average value of the areas of the holes opened in the other surface on the back side of the one surface is 1.5 times or more the average value of the areas of the holes opened in the one surface.
13. 13. The titanium porous body according to claim 11 or 12, wherein, The total thickness is 200 μm or more and 3000 μm or less.
14. 14. The titanium porous body according to any one of claims 11 to 13, wherein, The thickness of the porous layer constituting the portion on the one surface side is 30% or less of the total thickness.

Description

Method for producing titanium molded body, method for producing titanium porous body, and titanium porous body Technical Field The present invention relates to a method for producing a sheet-shaped titanium molded body, a method for producing a titanium porous body, and a titanium porous body. Background The titanium porous body produced by sintering the titanium powder has air permeability, liquid permeability, and electrical conductivity by micropores, and also has high corrosion resistance by forming a passivation film or the like on the surface. As a titanium porous body having such characteristics, a porous transport layer (Porous Transport Layer, PTL) or the like in an environment where corrosion may occur in a solid polymer (Polymer Electrolyte Membrane, PEM) type water electrolysis apparatus has been studied. In particular, hydrogen produced by a PEM-type or other type of water electrolysis apparatus using electric power derived from renewable energy sources is called green hydrogen, and has been highly expected in recent years for accelerating the progress of decarburization society. As a technique related to a titanium porous body, for example, patent document 1 describes a method for producing a porous metal laminate, which is characterized in that the porous metal laminate is composed of a plurality of layers including porous layers in which a plurality of polyhedral voids each having a skeleton of a metal sintered body formed in a side are formed in a continuous state, and the method for producing a porous metal laminate includes a lamination step of laminating the porous layers and adjacent layers made of a metal, and a fusing step of fusing the porous layers and the adjacent layers to a desired shape by a laser in a state in which the porous layers and the adjacent layers are laminated, and in the fusing step, a fusion bonding layer for bonding the porous layers and the adjacent layers is formed on side surfaces of the porous layers and the adjacent layers by melting and solidifying the porous layers by the laser. Further, patent document 2 describes "a composite material comprising a first region formed of a metal foam having a conductive metal component having a conductivity of 8MS/m or more at 20 ℃, and a second region formed of a metal foam having a soft magnetic metal component". Prior art literature Patent literature Patent document 1 Japanese patent laid-open publication No. 2011-106023 Patent document 2 Japanese patent application laid-open No. 2021-529891 Disclosure of Invention Problems to be solved by the invention When the titanium porous body is used as a porous transport layer in a PEM-type water electrolysis apparatus, the titanium porous body may be pressed against an electrolyte membrane to be assembled. In this case, if the pores on the surface of the titanium porous body are large, the electrolyte membrane pressed by the titanium porous body partially enters the pores, and is greatly deformed at a portion close to the pores, which may cause damage to the electrolyte membrane. Therefore, from the viewpoint of suppressing occurrence of damage to the electrolyte membrane, it is desirable that the porous titanium body has small pores that open on the surface on the electrolyte membrane side. Even if the number of holes in the surface is small, a certain level of air permeability or liquid permeability can be exhibited. However, when not only the surface pores but also the entire pores of the titanium porous body are small, the number of pores is large, and the required air permeability or liquid permeability may not be obtained at a required level. In order to solve this problem, it is considered that by stacking a plurality of porous layers, a porous layer having small pores is provided on one surface side to suppress damage to the electrolyte membrane, and a titanium porous body having a large void ratio is formed as a whole so that excellent air permeability and liquid permeability can be exhibited. When a titanium porous body having a plurality of porous layers is produced, if a plurality of titanium sintered bodies to be produced into a porous layer are stacked and heat-bonded, each porous layer constituting the titanium porous body is subjected to two times of high-temperature heating, heating for sintering at the time of producing the titanium sintered body and heating at the time of the bonding. As a result, the porous titanium body obtained by joining a plurality of titanium sintered bodies may have small pores as a whole, and may not have excellent air permeability or liquid permeability to the desired extent. This is also the case in the production of a titanium porous body having a plurality of porous layers having the same degree of size and number of pores, as well as in the production of a titanium porous body having a plurality of porous layers having different sizes and numbers of pores. The present invention aims to provide a method for producing a titanium mo