WO2023127361A1 - チタン多孔質体及び、チタン多孔質体の製造方法 - Google Patents
チタン多孔質体及び、チタン多孔質体の製造方法 Download PDFInfo
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- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 title claims abstract description 247
- 239000010936 titanium Substances 0.000 title claims abstract description 141
- 229910052719 titanium Inorganic materials 0.000 title claims abstract description 137
- 238000004519 manufacturing process Methods 0.000 title claims description 25
- 239000011148 porous material Substances 0.000 claims abstract description 62
- 238000009826 distribution Methods 0.000 claims abstract description 30
- 238000000465 moulding Methods 0.000 claims description 85
- 238000010438 heat treatment Methods 0.000 claims description 53
- 238000001816 cooling Methods 0.000 claims description 43
- 239000000843 powder Substances 0.000 claims description 35
- 239000002245 particle Substances 0.000 claims description 34
- 238000000151 deposition Methods 0.000 claims description 25
- 238000005245 sintering Methods 0.000 claims description 24
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 12
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 claims description 8
- 229910052799 carbon Inorganic materials 0.000 claims description 8
- 239000000463 material Substances 0.000 claims description 8
- 238000002360 preparation method Methods 0.000 claims description 8
- CPLXHLVBOLITMK-UHFFFAOYSA-N Magnesium oxide Chemical compound [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 claims description 4
- 229910002804 graphite Inorganic materials 0.000 claims description 4
- 239000010439 graphite Substances 0.000 claims description 4
- RUDFQVOCFDJEEF-UHFFFAOYSA-N yttrium(III) oxide Inorganic materials [O-2].[O-2].[O-2].[Y+3].[Y+3] RUDFQVOCFDJEEF-UHFFFAOYSA-N 0.000 claims description 4
- ODINCKMPIJJUCX-UHFFFAOYSA-N Calcium oxide Chemical compound [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 claims description 3
- 239000010453 quartz Substances 0.000 claims description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 3
- 230000006835 compression Effects 0.000 abstract description 19
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- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 7
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 7
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- 238000005259 measurement Methods 0.000 description 6
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- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 5
- 229910052753 mercury Inorganic materials 0.000 description 5
- 238000006356 dehydrogenation reaction Methods 0.000 description 4
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- -1 titanium hydride Chemical compound 0.000 description 4
- 229910000048 titanium hydride Inorganic materials 0.000 description 4
- PZNSFCLAULLKQX-UHFFFAOYSA-N Boron nitride Chemical compound N#B PZNSFCLAULLKQX-UHFFFAOYSA-N 0.000 description 3
- 230000007423 decrease Effects 0.000 description 3
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- 229910052718 tin Inorganic materials 0.000 description 2
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Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/10—Sintering only
- B22F3/11—Making porous workpieces or articles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
- B22F1/05—Metallic powder characterised by the size or surface area of the particles
- B22F1/052—Metallic powder characterised by the size or surface area of the particles characterised by a mixture of particles of different sizes or by the particle size distribution
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/02—Compacting only
- B22F3/03—Press-moulding apparatus therefor
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/04—Making non-ferrous alloys by powder metallurgy
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/04—Making non-ferrous alloys by powder metallurgy
- C22C1/045—Alloys based on refractory metals
- C22C1/0458—Alloys based on titanium, zirconium or hafnium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/08—Alloys with open or closed pores
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C14/00—Alloys based on titanium
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/50—Manufacturing or production processes characterised by the final manufactured product
Definitions
- the present invention relates to a sheet-like porous titanium body and a method for producing the porous titanium body.
- a porous titanium body can be produced by heating and sintering titanium powder, and is described in Patent Documents 1 to 3, for example.
- Patent Document 1 there is a description of "a porous material which is used as a current collector in a solid polymer type water electrolytic cell or a solid polymer type fuel cell and is made of a sintered body of spherical gas-atomized titanium powder. Quality conductive plate” is described.
- ⁇ It has a thickness of 5 ⁇ m to 60 ⁇ m, a porosity of 1% to 80%, a large number of isotropically communicating through holes, and a cylindrical mandrel test in which the diameter of the mandrel is gradually reduced.
- a current collector for a dye-sensitized solar cell which is composed of a porous sintered metal thin film that does not crack on the outer surface of the bent portion up to a diameter of 6 mm when bent instead of other materials.
- Patent Document 3 A method for producing a metal sintered body in which a sheet-like molded body made of metal powder is sintered by self-heating by energizing while running, wherein the heat-generating portion of the sheet-shaped molded body is generated by energization.
- JP-A-2002-275676 JP 2014-239023 A Japanese Unexamined Patent Application Publication No. 2011-202202
- a titanium porous body obtained by sintering titanium powder has gas permeability or liquid permeability and electrical conductivity due to a large number of pores, and a passive film is formed on the surface. It also has high corrosion resistance. For this reason, titanium porous bodies are being studied for use as PTLs (porous transport layers) and the like in environments where PEM water electrolysis devices can be corroded.
- the porous titanium body is sometimes required to have excellent compression resistance and have uniform pore sizes.
- compression resistance the titanium porous body can resist compressive force that may act when it is incorporated in a device such as a PEM water electrolysis device so that the required thickness or shape is maintained. it needs to be something.
- the pore size of the titanium porous body is not uniform, there is a concern that water and oxygen may flow locally at relatively large pores, resulting in a decrease in water electrolysis efficiency.
- a thin sheet-like titanium porous body is required.
- An object of the present invention is to provide a relatively thin sheet-like titanium porous body having excellent compression resistance and having pores of uniform size to some extent, and a method for producing the same.
- titanium powder having a predetermined particle size is thinly deposited on the molding surface of a mold in a dry process, and then heated at a high temperature to be sintered to achieve excellent compression resistance and uniformity. It was found that a sheet-like titanium porous body having fine pores can be obtained. However, if a titanium powder having a predetermined particle size is heated as it is at a high temperature, undulations and cracks are likely to occur after sintering due to its thin thickness, and a porous titanium body cannot be produced. In response to this, the inventor further attempted to suppress the occurrence of undulations and cracks by adjusting the form of the release layer on the molding surface and the cooling conditions after heating. As a result, it has become possible to produce the titanium porous body described above.
- the titanium porous body of the present invention is in the form of a sheet, has a thickness of 0.3 mm or less, a compressive strain amount of 0.20 or less when pressurized at 80 MPa, and has pore diameters and volumes of The half width of the first peak with the highest peak height in the pore size distribution showing the relationship between is 3.5 ⁇ m or less, and the peak height of the second peak with the highest peak height next to the first peak is It is 10% or less of the peak height of the first peak.
- the pore diameter at the position where the first peak appears in the pore size distribution is 10.0 ⁇ m or less.
- the above titanium porous body preferably has a porosity of 45% or less.
- the titanium porous body may have an area of 10000 mm 2 or more. It is preferable that the titanium porous body has a Ti content of 98% by mass or more.
- the peak height of the second peak is preferably 5% or less of the peak height of the first peak.
- the method for producing a porous titanium body of the present invention is a method for producing a sheet-like porous titanium body by heating and sintering titanium powder on the molding surface of a mold, wherein the 10% particle diameter D10 is A powder preparation step of preparing a titanium powder having a diameter of 5 ⁇ m or more and 15 ⁇ m or less and a 90% particle diameter D90 of 15 ⁇ m or more and 25 ⁇ m or less, and a release layer forming step of forming a release layer in an easy peeling region other than the adhesion region; after the release layer forming step, a powder depositing step of dry depositing the titanium powder on the molding surface; After the deposition step, a heating step of heating the titanium powder on the molding surface to a maximum temperature of 950° C.
- the molding a cooling step in which the sintered body is cooled on the surface and the time required for cooling from 950° C. to 800° C. is at least 1500 seconds or less, and a titanium porous body having a thickness of 0.3 mm or less is manufactured. It is to do.
- a titanium porous body having an area of 10000 mm 2 or more may be manufactured.
- the titanium powder prepared in the powder preparation step has an average circularity of 0.83 or less.
- the material of the mold having the molding surface is selected from the group consisting of carbon, quartz, graphite, magnesia (MgO), calcia (CaO), zirconia (ZrO 2 ) and yttria (Y 2 O 3 ). It is preferable to include at least one selected.
- the time for heating the titanium powder to 950° C. or higher in the heating step is 30 to 480 minutes.
- the titanium porous body of the present invention is in the form of a relatively thin sheet, has excellent compression resistance, and has pores of uniform size to some extent. Also, the method for producing a titanium porous body of the present invention is suitable for producing such a titanium porous body.
- FIG. 1 is a schematic cross-sectional view showing the main configuration of a compressing device that can be used for measuring the compressive strain amount of a titanium porous body
- FIG. 4 is a graph showing an example of pore size distribution of a titanium porous body.
- FIG. 3(a) is a plan view showing an example of a mold that can be used in a method for producing a titanium porous body according to one embodiment of the present invention
- FIG. 3(b) is a plan view of FIG. 3(a). ) along the line bb.
- FIG. 4(a) is a plan view showing the mold of FIG. 3 with a release layer formed on the easily peelable region of the molding surface
- FIG. 4(b) is a plan view of FIG. 4(a).
- FIG. 5(a) is a plan view showing the mold and release layer of FIG. 4 together with titanium powder deposited on the molding surface
- FIG. 5(b) is bb of FIG. 5(a).
- 1 is a cross-sectional view along a line
- FIG. FIG. 6(a) is a plan view showing the porous titanium body manufactured according to FIGS. 3 to 5
- FIG. 6(b) is a cross-sectional view taken along line bb in FIG. 6(a).
- 4 is a graph showing the pore size distribution of the titanium porous body of Example 1.
- FIG. 4 is a graph showing the pore size distribution of the titanium porous body of Comparative Example 3.
- FIG. 5(a) is a plan view showing the mold and release layer of FIG. 4 together with titanium powder deposited on the molding surface
- FIG. 5(b) is bb of FIG. 5(a).
- 1 is a cross-sectional view along a line
- FIG. FIG. 6(a) is a plan view
- a titanium porous body according to one embodiment of the present invention is a sheet-like body having a thickness of 0.3 mm or less, a compressive strain amount of 0.20 or less when pressurized at 80 MPa, and pores
- the first peak with the highest peak height in the pore size distribution showing the relationship between the diameter and volume of the peak has a half width of 3.5 ⁇ m or less, and the second peak with the highest peak height next to the first peak.
- the height is 10% or less of the peak height of the first peak.
- a method for manufacturing a titanium porous body includes a powder preparation process, a release layer forming process, a powder depositing process, a heating process, and a cooling process.
- the powder preparation step titanium powder having a 10% particle size D10 of 5 ⁇ m or more and 15 ⁇ m or less and a 90% particle size D90 of 15 ⁇ m or more and 25 ⁇ m or less is prepared.
- the heating step the titanium powder is heated to a maximum temperature of 950° C. or higher to obtain a sintered body. As a result, the finally produced porous titanium body has excellent compression resistance and relatively uniform pore sizes.
- the sintered body is strongly adhered to the molding surface and peeling is difficult unless a release layer is formed on the molding surface. This will cause cracks.
- the mold release layer is formed on the entire molding surface, the titanium powder deposited thereon is slippery and causes irregular shrinkage, resulting in waviness in the sintered body.
- the release layer is not formed in the adhesion region of the outer edge of the molding surface, and the release layer is formed in the easy peeling region other than the adhesion region. .
- the titanium powder is sintered while adhering to the bonding region at the location located on the bonding region.
- irregular shrinkage of the titanium powder during heating is suppressed, and the sintered body has a flat shape without undulations.
- the sintered body in the cooling step, is cooled on the molding surface, and at least the time required for cooling from 950°C to 800°C is set to 1500 seconds or less.
- the sintered body tends to naturally separate from the bonding area due to thermal shock at that time, and after cooling, the sintered body tends to separate from the mold. Easier to take out.
- the sintered body has high toughness due to the high temperature, so it is considered that cracks do not occur even by the action of thermal shock.
- the titanium porous body is made of titanium. If it is made of titanium, a titanium porous body having a certain relative density and high electrical conductivity can be obtained.
- the titanium porous body has a Ti content of, for example, 98% by mass or more, preferably 99% by mass or more. Although it is desirable that the Ti content is large, it may be 99.8% by mass or less.
- a titanium porous body may contain Fe as an impurity, and the Fe content is, for example, 0.25% by mass or less.
- the titanium porous body may contain Ni, Cr, Al, Cu, Zn, and Sn as unavoidable impurities resulting from the manufacturing process, for example.
- the content of each of Ni, Cr, Al, Cu, Zn and Sn is preferably less than 0.10% by mass, and the total content thereof is preferably less than 0.30% by mass.
- the titanium porous body for example, has an oxygen content of 0.15% by mass to 0.50% by mass, a nitrogen content of 0.02% by mass to 0.20% by mass, and a carbon content of It may be from 0.02% to 0.20% by weight.
- the oxygen content can be measured by an inert gas fusion-infrared absorption method
- the nitrogen content can be measured by an inert gas fusion-thermal conductivity method
- the carbon content can be measured by a combustion infrared absorption method.
- the titanium porous body may have a purity corresponding to JIS H 4600 (2012) Types 1 to 4, typically Types 1 to 2, except for the above oxygen content.
- the sheet-like porous titanium body has a thickness of 0.3 mm or less, preferably 0.2 mm to 0.3 mm. By increasing the thickness to a certain extent, non-uniform diffusion of oxygen and water can be suppressed in the application of the PEM water electrolysis device, and a decrease in electrolysis efficiency can be suppressed.
- the "sheet-like" of the porous titanium body means a plate-like or foil-like shape having a smaller thickness than the dimensions in plan view, and the shape in plan view is not particularly limited.
- the thickness is measured at a total of 5 points, 4 points at the periphery and 1 point at the center of the titanium porous body, for example, Mitutoyo's digital thickness gauge (model number 547-321), etc., with a flat type probe with a ⁇ 10 mm measurement accuracy of 0. Measured using a digital thickness gauge of 0.001 to 0.01 mm, and taken as the average value of those measurements.
- Mitutoyo's digital thickness gauge model number 547-321
- the titanium porous body has a compressive strain amount of 0.20 or less when a pressure of 80 MPa is applied. When this compressive strain amount is small, the titanium porous body can be evaluated as having excellent compression resistance, and the required thickness and shape can be maintained inside a device such as a PEM water electrolysis device.
- the above compressive strain amount is preferably 0.18 or less, and may be, for example, 0.13 to 0.18.
- the compression strain amount of the titanium porous body can be measured using a compression device 51 as shown in FIG.
- the compressing device 51 includes a lower jig 52 having a mounting table 52a on which a sample St of the porous titanium material St is mounted, and an upper jig 52 arranged above the lower jig 52 so as to face the mounting table 52a. a jig 53; and two displacement gauges 55 for measuring the displacement of the upper jig 53 with respect to the lower jig 52 .
- a square-shaped sample St having a plan view of 20 mm square is cut out from the titanium porous body.
- this sample St is placed between the upper jig 53 and the mounting table 52 a of the compression device 51 .
- the pressurizing mechanism 54 is operated to displace the upper jig 53 toward the lower jig 52 side, and a gap between the upper jig 53 and the mounting table 52a is maintained.
- the sample St is sandwiched between and compressed.
- the displacement speed of the upper jig 53 can be kept constant at 0.1 mm/min.
- the thickness Tb of the sample St under pressure is obtained from the displacement measured by the displacement gauge 55 when a pressure of 80 MPa is applied to the sample St. Further, the displacement amount T0 of the displacement meter 55 when a pressurizing force of 80 MPa is applied in a state where the sample St is not arranged in the compression device 51 is obtained.
- a porous titanium body has a large number of pores.
- the pore size distribution which indicates the relationship between the diameter and volume of each pore, can be measured by mercury porosimetry.
- Mercury intrusion can be performed using Autopore IV9500 manufactured by Micromeritech. In this case, the mercury intrusion pressure is 14 to 227 MPa, the measurement mode is the pressurization process, the measurement cell volume is 3.9 cm 3 , the mercury contact angle is 141.3°, and the mercury surface tension is 484 dyn/cm. It can be measured by measuring a porous titanium sample.
- the measurement results can be represented by a graph in which the horizontal axis is the pore diameter and the vertical axis is the pore volume, as illustrated in FIG.
- At least one peak appears in the pore size distribution of the titanium porous body.
- the peak with the highest peak height among them is called the first peak.
- the pore size distribution has only one peak, that peak is referred to as the first peak.
- the half width of the first peak is 3.5 ⁇ m or less.
- the half-value width of the first peak means the width of the peak of the first peak at half the peak height Hf (Hf/2), as shown in FIG.
- the half width of the first peak is small, the pore size distribution is sharp and the pore size is recognized to be uniform.
- the half width of the first peak is preferably 3.0 ⁇ m or less, more preferably 2.5 ⁇ m or less.
- the half-value width of the first peak is preferably as small as possible, but may be, for example, 1.5 ⁇ m or more.
- the diameter of the pores at the position where the first peak appears in the pore size distribution is preferably 10.0 ⁇ m or less, more preferably 9.0 ⁇ m or less.
- the FWHM of the first peak is small and the first peak appears at a relatively small diameter position, so that the pores have a sharp distribution on the small diameter side.
- the diameter of the pores at the position where the first peak appears is preferably 3.0 ⁇ m or more. Good flowability of the fluid can be ensured by having a diameter of the pores at the position where the first peak appears to be large to some extent.
- the pore size distribution does not have peaks other than the first peak and has only the first peak. This is because it can be said that a titanium porous body having such a pore size distribution has relatively uniform pore sizes.
- peaks other than the first peak may appear in the pore size distribution.
- a peak having the next highest peak height after the first peak is referred to as a second peak.
- the peak height Hs of the second peak which is the second highest after the first peak, is preferably 10% or less, more preferably 5% or less of the peak height Hf of the first peak.
- the porosity of the titanium porous body is preferably 45% or less. If the porosity is of this order, it is possible to achieve the air permeability or liquid permeability required according to the application.
- the porosity of the titanium porous body may be 30% or more.
- the surface area of the sheet-like porous titanium material in plan view may be 10,000 mm 2 or more, or 40,000 mm 2 or more depending on the application.
- the area of the titanium porous body is, for example, 40,000 mm 2 to 600,000 mm 2 .
- this embodiment by adopting the manufacturing method described later, the generation of undulations and cracks is suppressed, and even a large titanium porous body can be manufactured.
- An embodiment of the method for producing a titanium porous body includes a powder preparation step of preparing titanium powder having a predetermined particle size, and a release layer forming step of forming a release layer on a predetermined region of the molding surface of the mold. , After the release layer forming step, a powder deposition step of dry depositing titanium powder on the molding surface, a heating step of heating the titanium powder deposited on the molding surface, and after the heating step, on the molding surface and a cooling step of cooling the sintered body so that the time required for cooling from 950° C. to 800° C. is at least 1500 seconds or less.
- the titanium powder has a 10% particle size D10 of 5 ⁇ m or more and 15 ⁇ m or less and a 90% particle size D90 of 15 ⁇ m or more and 25 ⁇ m or less. Unless the titanium powder satisfies this particle size requirement, it is impossible to obtain a titanium porous body having high compression resistance and uniform pore sizes. From this point of view, the 10% particle size D10 of the titanium powder is preferably 7 ⁇ m or more and 12 ⁇ m or less. From the same point of view, the 90% particle size D90 is preferably 17 ⁇ m or more and 23 ⁇ m or less.
- the above 10% particle size D10 and 90% particle size D90 mean particle sizes at which the volume-based cumulative distribution is 10% or 90%, respectively, in the particle size distribution obtained by the laser diffraction scattering method.
- the titanium powder satisfies the above particle size conditions, there are no particular restrictions on its shape or form, or on the production method.
- pulverized powder such as hydrodehydrogenated titanium powder (so-called HDH powder)
- HDH powder hydrodehydrogenated titanium powder
- the hydrodehydrogenated titanium powder is obtained by hydrogenating sponge titanium or the like, pulverizing it, and then dehydrogenating it.
- titanium hydride powder which has not been dehydrogenated after the pulverization can be used.
- the hydrogen content of the titanium hydride powder is preferably 5% by mass or less.
- the titanium powder have an average circularity of 0.83 or less.
- the pulverized powder described above tends to have a relatively small average circularity.
- the average circularity is obtained as follows. Using an electron microscope, measure the perimeter (A) of the projected area of the particles of the titanium powder, and the ratio of the perimeter (B) of a circle having the same area as the projected area is defined as circularity (B/A). .
- the average circularity is obtained by flowing particles together with a carrier liquid in a cell, capturing images of a large number of particles with a CCD camera, and obtaining the above circularity (B/A) for each particle from 1000 to 1500 individual particle images. is calculated and obtained as the average value of the circularity of each particle.
- the above circularity value increases as the shape of the particle approaches a true sphere, and the circularity of a particle having a perfect spherical shape is 1.00. Conversely, the circularity value decreases as the shape of the particles departs from a true sphere.
- a skeleton of a three-dimensional network structure that partitions the pores of the titanium porous body is formed. , tend to be like sponge titanium.
- the skeleton of this titanium sponge-like three-dimensional network structure is similar in shape to titanium sponge produced by the Kroll method.
- a titanium powder which is a pulverized powder or a titanium powder having a small average circularity is used, a titanium porous body having a sponge titanium skeleton and a sheet-like outer shape can be obtained.
- the skeleton of the three-dimensional network structure that partitions the pores of the titanium porous body often becomes a non-woven fabric.
- a method of using a paste containing titanium powder, an organic binder, etc., drying the paste, and then sintering the titanium powder instead of the method of depositing titanium powder on the molding surface, a method of using a paste containing titanium powder, an organic binder, etc., drying the paste, and then sintering the titanium powder, When a foaming agent is included, the titanium porous body produced thereby tends to have voids formed also in the skeleton due to the effect of the foaming agent.
- the above titanium powder is deposited on the molding surface of the mold, but prior to the deposition, a release layer forming step is performed.
- a release layer is formed on a predetermined region of the molding surface.
- a sheet-like porous metal body which is a sintered body of titanium powder, has an undulating shape or a wavy shape.
- the release layer 3 is formed in the easy peeling region Ar without forming the release layer 3 in the adhesion region Aa, and the titanium powder 4 is added to the release layer 3 in the heating step described later. It is made to adhere to the adhesion region Aa where there is no adhesive (see FIG. 5).
- the bonding region Aa where the release layer 3 is not present reacts with the titanium powder 4 deposited thereon to bond with the heating.
- the titanium powder 4 that is being sintered is fixed in the adhesive region Aa of the outer edge, and thus random thermal shrinkage of the titanium powder 4 on the release layer 3 is suppressed.
- the easy-peeling region Ar means a region where the sintered body 4a is easily peeled off after sintering due to the presence of the release layer 3 on the surface, compared to the adhesion region Aa where the release layer 3 is not present. do.
- the outer edge portion of the molding surface 2 be the adhesive region Aa where the release layer 3 does not exist over the entire circumference, as in the illustrated example. .
- the release layer 3 is formed only on the easy peeling region Ar of the adhesive region Aa and the easy peeling region Ar of the molding surface 2.
- Titanium powder 4 is deposited on the surface 2 not only on the easily peelable area Ar but also on the adhesive area Aa.
- the release layer 3 on the molding surface 2 consists of titanium powder 4 deposited in the adhesion region Aa around the release layer 3 and The whole will be surrounded by the titanium powder 4 deposited on the mold layer 3 .
- the surface area of the molding surface 2 on which the titanium powder 4 is deposited in the powder deposition process (in the illustrated example, the sum of the surface area of the adhesion region Aa and the surface area of the easy peeling region Ar) is larger than the surface area of the easy peeling region Ar.
- the ratio (Ss/Sr) of the surface area Ss on which the titanium powder 4 is deposited on the molding surface 2 in the powder depositing step to the surface area Sr of the easily peelable region Ar may be determined as appropriate, for example, 1.05 to 1.50. and may be, for example, 1.10 to 1.35.
- the effect of suppressing the undulation of the sintered body 4a as described above can be sufficiently obtained.
- the surface area Ss on which the titanium powder 4 is deposited is not made too large with respect to the surface area Sr of the easy peeling region Ar, it will be difficult to remove the sintered body 4a after sintering from the molding surface 2. can be suppressed.
- the release layer 3 can be formed by applying a release agent containing, for example, boron nitride (BN) and/or titanium boride (TiB 2 ) to the easily peelable region Ar of the molding surface 2.
- a release agent containing, for example, boron nitride (BN) and/or titanium boride (TiB 2 )
- BN boron nitride
- TiB 2 titanium boride
- the release layer 3 may be formed by applying a liquid such as slurry in which fine particles of boron nitride and/or titanium boride are dispersed in a solvent as a release agent to the molding surface 2 . In this case, it is preferable to dry the release layer 3 before depositing the titanium powder 4 .
- the material of the mold 1 having the molding surface 2 may be any material as long as it can adhere to the titanium powder 4 with an appropriate strength by sintering. It preferably contains at least one selected from the group consisting of (CaO), zirconia (ZrO 2 ) and yttria (Y 2 O 3 ). Mold 1 is made of, for example, carbon, quartz, graphite, magnesia, calcia, zirconia, or yttria. Furthermore, the mold 1 may be made of carbon or graphite.
- the titanium powder 4 is fixed to the molding surface 2 by adhesion in the adhesion region Aa of the titanium powder 4 during sintering, so that waviness of the sintered body 4a can be suppressed satisfactorily. be done.
- the molding die 1 has a rectangular shape such as a square in a plan view as a whole, and includes a bottom wall 5 having a molding surface 2 and an outer edge portion of the bottom wall 5 which is erected for molding. A side wall 6 surrounding the surface 2 over the entire circumference is provided. Inside the side wall 6 and on the molding surface 2 a space is defined in which the titanium powder 4 is deposited.
- the molding surface 2 may have, for example, an appropriate polygonal, elliptical, or circular shape in plan view.
- a mold without side walls 6 can be used as the mold 1, as the mold 1, a mold without side walls 6 can be used.
- titanium powder 4 is deposited dry.
- dry means that liquid such as solvent or binder is not used.
- the titanium powder 4 is not deposited in a slurry in which the titanium powder 4 is dispersed in a liquid, but is deposited by dropping the titanium powder 4 in a gas such as air or in a vacuum.
- the titanium powder 4 is deposited on the release layer 3 in the easy-peeling region Ar where the release layer 3 exists.
- the titanium powder 4 comes into contact with the adhesion area Aa and deposits the titanium powder 4 directly on the adhesion area Aa.
- the powder depositing step it is preferable to deposit the titanium powder 4 without pressurization at least in the deposition direction in order to obtain a titanium porous body having a predetermined air permeability or liquid permeability. This is because if pressure is intentionally applied in the deposition direction, the titanium porous body becomes dense after sintering, and air permeability or liquid permeability is lowered.
- the finally produced titanium porous body has a relatively large first peak in the pore size distribution described above and a sufficiently small second peak. Or they tend to be almost non-existent and the pore sizes tend to be uniform.
- the inside of the side wall 6 is covered with the titanium powder 4 that is shaken off from above.
- a plate-like spatula or the like is moved along the upper surface of the side wall 6 to remove part of the titanium powder 4 that has risen above the upper surface of the side wall 6. are removed outside the side wall 6 .
- a scraping tool such as a flat spatula.
- the titanium powder 4 is not intentionally pressurized in its deposition direction.
- the titanium powder 4 can be deposited inside the side wall 6 of the mold 1 by the height of the side wall 6 .
- the titanium powder 4 is placed in a furnace together with the molding die 1 and heated to obtain a sintered body 4a having a sheet-like shape or the like corresponding to the space on the molding surface 2 of the container-shaped molding die 1. be done.
- the thickness of the sheet-like porous metal body can be adjusted by changing the height of the sidewall 6 of the mold 1 or the like.
- the thickness of the titanium powder 4 deposited on the molding surface 2 can be appropriately set according to the thickness of the titanium porous body to be manufactured.
- the deposition thickness Tf of the titanium powder 4 deposited on the easy peeling region Ar can be appropriately set in consideration of the thickness Tp of the titanium porous body and the like.
- a heating process is performed to heat the titanium powder 4 on the molding surface 2 to a maximum temperature of 950°C or higher.
- a sintered body 4a is obtained on the molding surface 2.
- the heating to the highest temperature of 950° C. or higher causes the following to occur. That is, the titanium powder 4 is sintered as a whole, and the titanium powder 4 in contact with the adhesion area Aa without the release layer 3 intervening sticks to the adhesion area Aa.
- the titanium powder 4 sticking and being fixed to the adhesive region Aa at the outer edge of the molding surface 2 suppresses the random shrinkage of the titanium powder 4 on the release layer 3 in the easy peeling region Ar.
- the sintered body 4a formed by sintering the titanium powder 4 is prevented from waviness and cracking.
- the titanium powder 4 can be heated and sintered under a reduced pressure atmosphere such as a vacuum or in an inert atmosphere. This can prevent the titanium powder 4 from being excessively oxynitrided during sintering.
- a reduced pressure atmosphere such as a vacuum or in an inert atmosphere.
- the sintering of the titanium powder 4 can be performed, for example, in a vacuum furnace with a degree of vacuum reaching 10 ⁇ 4 Pa to 10 ⁇ 2 Pa under a reduced pressure atmosphere.
- the sintering of the titanium powder 4 can be performed in an inert atmosphere with an argon gas atmosphere. Note that nitrogen gas does not correspond to an inert gas here.
- the maximum temperature reached in the heating process shall be 950°C or higher. If it is less than 950° C., there is a possibility that the compression resistance of the finally produced porous titanium body may be lowered, or the uniformity of the pore size may be deteriorated.
- the highest temperature reached is preferably 1000° C. or higher.
- the maximum temperature reached is preferably 1200° C. or lower, more preferably 1100° C. or lower.
- the temperature it is preferable to set the temperature to 950°C or higher for 30 minutes to 480 minutes, more preferably 60 minutes to 360 minutes.
- the titanium powders 4 can be sufficiently strongly bonded to each other, and the strength of the titanium porous body can be further increased.
- densification of the titanium porous body due to excessive sintering is suppressed, and the titanium porous body can satisfactorily exhibit the required air permeability or liquid permeability. become able to.
- the titanium powder 4 contains titanium hydride
- the heating temperature and heating time in the dehydrogenation step can be appropriately determined in view of the content of the titanium hydride powder.
- the dehydrogenation step can be performed in a vacuum furnace under a reduced pressure atmosphere with a degree of vacuum reaching 10 -4 Pa to 10 -2 Pa.
- the heating step may be performed after cooling once, or the heating step may be performed by further raising the temperature without cooling.
- the sintered body 4a is cooled on the molding surface 2. After the heating process, the sintered body 4a is adhered on the molding surface 2 at the bonding area Aa of the outer edge of the molding surface 2, and the heat during heating is increased by heating while the periphery is fixed in the heating process. It is considered that tensile stress due to contraction is generated. If the sintered body 4a is cooled at a relatively slow rate during subsequent cooling, cracks will occur in the sintered body 4a when the sintered body 4a is peeled off from the molding surface 2 .
- the cooling step when the sintered body 4a is cooled on the molding surface 2, at least the time required for cooling from 950°C to 800°C is set to 1500 seconds or less. That is, the cooling rate is increased at least while in the predetermined high temperature range. It is considered that the thermal shock acts on the sintered body 4a at a high temperature and in a state of high toughness by cooling at a relatively high rate in a predetermined high temperature range. As a result, the portion of the sintered body 4a that is adhered to the adhesion area Aa is naturally peeled off, and the sintered body 4a can be easily removed from the mold 1 after the cooling process without cracking.
- the time in the predetermined high temperature range be short. Therefore, the time required for cooling from 950° C. to 800° C. should be 1500 seconds or less, preferably 600 seconds or less. Although there is no particular problem if the cooling rate at this time is too fast, there is no further advantage, and realizing such a high cooling rate is not realistic in terms of the structure of the furnace.
- the time required for cooling from 950° C. to 800° C. may be, for example, 30 seconds or longer, and may be 60 seconds or longer.
- the sintered body 4a is quenched to 950° C. to 800° C. in a short period of time as described above, the sintered body 4a will naturally peel off from the molding surface 2, so that the sintered body 4a is then fired from the molding die 1. It becomes easy to take out the binding body 4a. In the temperature range lower than 800°C, cooling at such a high rate is not required.
- the cooling process it is preferable to supply an inert gas such as argon or helium in the furnace and cool the sintered body 4a while stirring the inert gas in order to shorten the cooling time and rapidly cool the sintered body.
- an inert gas such as argon or helium
- the sintered body 4a is cooled not only by radiation but also by convection and conduction using an inert gas as a medium, so that it can be cooled in a short period of time.
- the inert gas can be agitated by installing a fan in the furnace and operating the fan during the period of increasing the cooling rate of the cooling process.
- the cooling process can be performed in the furnace used in the heating process, or can be performed in another facility or place by moving the sintered body 4a together with the mold 1 from the furnace used in the heating process. .
- the sintered body 4a of the titanium powder 4 is removed from the mold 1.
- the sintered body 4a of the titanium powder 4 may be taken out after the temperature is lowered to 100° C. or lower.
- the sintered body 4a tends to spontaneously peel off due to thermal shock at the portion adhered to the adhesion region Aa at that time, and can be easily removed from the mold 1 after cooling.
- the release layer 3 is formed of a release agent powder
- the release agent powder may enter the surface of the sintered body 4a in contact with the release layer 3 to some extent. , such powder can be removed by an appropriate technique such as blowing air or washing with water.
- the sintered body 4a taken out from the molding surface 2 is separated from the adhesive area Aa and the easy-peeling area Ar to remove the outer edge portion located on the adhesive area Aa.
- the inner part of the mold 1, which is located on the release layer 3 of the easy peeling area Ar and is not substantially adhered to the molding surface 2 is taken out as a titanium porous body. can be done.
- the thickness of the porous titanium body taken out by the above cutting becomes more uniform.
- porous titanium body of the present invention was produced as a trial and its performance was evaluated, which will be described below.
- the description herein is for illustrative purposes only and is not intended to be limiting.
- a titanium powder having a particle size shown in Table 1 was prepared, deposited on the molding surface of the mold in a dry process, heated and then cooled to produce a porous titanium body having a thickness and area shown in Table 1.
- As the titanium powder HDH powder made of pure titanium having a hydrogen content of 0.5% by mass or less and an average circularity of 0.83 or less was used.
- All of the titanium porous bodies produced in Examples 1 to 5 and Comparative Examples 1 to 6 had a titanium purity of 99% by mass or more, an oxygen content of 0.15% by mass to 0.50% by mass, and nitrogen. The content was within the range of 0.02% by mass to 0.20% by mass, and the carbon content was within the range of 0.02% by mass to 0.20% by mass. The content of other unavoidable impurities was within a negligible range.
- Example 1 to 5 and Comparative Examples 1 to 4 a bonding region where no release layer was formed was provided on the outer edge of the molding surface of the carbon mold. As a result, it is believed that the titanium powder positioned at the outer edge portion was sintered while adhering to the bonding region during heating.
- the molding surface was square, and the adhesive area was provided to have a width of 1 to 5 mm so as to surround the entire periphery of the easily peelable area. Boron nitride powder was used for the release layer.
- Comparative Example 5 was the same as Example 1, except that no release layer was formed.
- Comparative Example 6 was the same as Example 1, except that a release layer was formed over the entire molding surface.
- the heating time (sintering time) during sintering was the time shown in Table 1. This sintering time is the time to reach 950° C. or higher as described above. Further, the pressure in the furnace during heating was set to 1 ⁇ 10 ⁇ 2 Pa or less. The maximum temperature reached during heating and the time required for cooling from 950° C. to 800° C. are as shown in the “cooling period” column of Table 1. After the inside of the furnace was cooled to 100° C. or less, the sintered body was taken out. In Examples 1 to 4 and Comparative Examples 2, 3, 5 and 6, argon gas was supplied into the furnace during cooling to lower the temperature of the sintered body as cooling with gas stirring. In Example 5, argon gas was supplied into the furnace during cooling, but the temperature of the sintered body was lowered while the argon gas was enclosed without stirring.
- the air permeability variation of each titanium porous body was evaluated.
- the air permeability was measured with a Gurley densometer manufactured by Toyo Seiki Seisakusho Co., Ltd., and was measured in accordance with JIS P8117, except that the inner diameter of the gasket was 6.0 mm instead of 28.6 mm.
- the time required t (s/300ml) for air to pass through was considered as breathability.
- the same sample was measured six times at different measurement locations, and the maximum value was t Max and the minimum value was t Min , and (t Max )/(t Min ) was regarded as the variation in breathability. .
- the presence or absence of cracks was visually confirmed.
- the presence or absence of waviness was determined by placing the porous titanium body on a flat surface and measuring the maximum height from the position of the flat surface to the highest position on the surface of the test piece in the thickness direction. It was judged that there was undulation when it exceeded 1.5 mm.
- Comparative Example 1 since the cooling rate after heating and sintering was slow, cracks occurred when the sintered body was separated from the molding surface. Therefore, in Comparative Example 1, a sheet-like porous titanium body could not be properly produced, and therefore the porous titanium body was not evaluated.
- Comparative Example 2 since the highest temperature reached during heat sintering was low, the half-value width of the first peak in the pore size distribution of the titanium porous body increased, resulting in variations in air permeability. In addition, in the titanium porous body of Comparative Example 2, the pore diameter at the position of the first peak in the pore diameter distribution was large, and the amount of compressive strain was large.
- Comparative Example 3 because the 90% particle size D90 of the titanium powder was outside the predetermined range, the peak height of the second peak of the pore size distribution increased, resulting in variations in air permeability.
- Comparative Example 4 although the cooling rate was slow, the sintered body did not crack because the maximum temperature reached during the previous heating was low. However, in Comparative Example 4, since the highest temperature reached was low, the compressive strain amount of the titanium porous body was large, and the half-value width of the first peak of the pore size distribution was large, resulting in variations in air permeability.
- Comparative Example 5 since no release layer was formed on the molding surface, the sintered body stuck to the molding surface and cracked when it was peeled off. Furthermore, there were parts where the peeling itself was difficult and shattered. In Comparative Example 6, undulations occurred in the sintered body due to the release layer formed on the entire molding surface. Therefore, in Comparative Examples 5 and 6, the sheet-like porous titanium bodies could not be produced properly, and therefore the porous titanium bodies were not evaluated.
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Abstract
Description
上記のチタン多孔質体のTi含有量は98質量%以上であることが好ましい。
上記のチタン多孔質体では、前記第二ピークのピーク高さが、前記第一ピークのピーク高さの5%以下であることが好ましい。
上記の製造方法では、前記粉末準備工程で準備する前記チタン粉末の平均円形度が0.83以下であることが好ましい。
上記の製造方法では、前記成形面を有する成形型の材質は、カーボン、石英、グラファイト、マグネシア(MgO)、カルシア(CaO)、ジルコニア(ZrO2)及びイットリア(Y2O3)からなる群から選択される少なくとも一種を含むことが好ましい。
上記の製造方法では、前記加熱工程で、前記チタン粉末を950℃以上にする時間を、30分~480分とすることが好ましい。
この発明の一の実施形態のチタン多孔質体は、厚みが0.3mm以下であるシート状のものであって、80MPaでの加圧時の圧縮ひずみ量が0.20以下であり、細孔の直径と容積との関係を示す細孔径分布におけるピーク高さが最も高い第一ピークの半値幅が3.5μm以下であり、前記第一ピークの次にピーク高さが高い第二ピークのピーク高さが、前記第一ピークのピーク高さの10%以下である。
チタン多孔質体は、チタン製とする。チタン製であれば、ある程度の相対密度で高い電気伝導性を有するチタン多孔質体が得られる。チタン多孔質体のTi含有量は、たとえば98質量%以上、好ましくは99質量%以上である。Ti含有量は多いほうが望ましいが、99.8質量%以下となることがある。
シート状のチタン多孔質体の厚みは、0.3mm以下であり、好ましくは0.2mm~0.3mmである。ある程度厚い厚みとすることにより、PEM水電解装置の用途にて酸素や水の不均一な拡散が抑えられ、電解効率の低下を抑制することができる。なお、チタン多孔質体についての「シート状」とは、平面視の寸法に対して厚みが小さい板状もしくは箔状を意味し、平面視の形状については特に問わない。
チタン多孔質体は、80MPaの加圧力を作用させた際の圧縮ひずみ量が0.20以下である。この圧縮ひずみ量が少ない場合、チタン多孔質体は耐圧縮性に優れたものであると評価することができ、PEM水電解装置等の装置内部で必要な厚み及び形状が維持され得る。上記の圧縮ひずみ量は、0.18以下であることが好ましく、たとえば0.13~0.18となる場合がある。
チタン多孔質体は、多数の細孔が形成されたものである。それらの各細孔の直径と容積との関係を示す細孔径分布は、水銀圧入法により測定することができる。水銀圧入法は、マイクロメリテック社製オートポアIV9500を用いて行うことができる。この場合、水銀圧入圧力は14~227MPa、測定モードは昇圧過程、測定セル容積は3.9cm3、水銀接触角141.3°、水銀表面張力484dyn/cmとして、0.35~0.50gのチタン多孔質体サンプルを測定することで測定可能である。その測定結果は、図2に例示するような、細孔の直径を横軸として細孔の容積を縦軸としたグラフで表すことができる。
チタン多孔質体の空隙率は、好ましくは45%以下である。空隙率がこの程度の大きさであれば、用途に応じて求められる通気性もしくは通液性を実現することができる。チタン多孔質体の空隙率εは、チタン多孔質体の幅、長さ及び厚みより求められる体積及び、質量から算出した見かけ密度ρ´と、チタン多孔質体を構成するチタンの真密度ρ(4.51g/cm3)を用いて、式:ε=(1-ρ´/ρ)×100により算出する。チタン多孔質体の空隙率は、30%以上になる場合がある。
シート状のチタン多孔質体の平面視における表面の面積は、用途に応じて、10000mm2以上、さらに40000mm2以上とすることがある。チタン多孔質体の面積は、たとえば40000mm2~600000mm2である。このような大型のシート状のチタン多孔質体を製造しようとすると、従来は、うねりや割れが発生して製造が困難であった。これに対し、この実施形態では、後述するような製造方法を採用することにより、うねりや割れの発生が抑制され、大型のチタン多孔質体であっても製造することが可能である。
チタン多孔質体の製造方法の実施形態には、所定の粒径のチタン粉末を準備する粉末準備工程と、成形型の成形面における所定の領域に離型層を形成する離型層形成工程と、離型層形成工程の後、成形面上にチタン粉末を乾式で堆積させる粉末堆積工程と、成形面上に堆積させたチタン粉末を加熱する加熱工程と、加熱工程の後、成形面上で前記焼結体を冷却し、少なくとも、950℃から800℃までの冷却にかかる時間を1500秒以下とする冷却工程とが含まれる。
2 成形面
3 離型層
4 チタン粉末
4a 焼結体
5 底壁
6 側壁
Ar 易剥離領域
Aa 接着領域
Tf チタン粉末の堆積厚み
Tp チタン多孔質体の厚み
Ct 切断箇所
Claims (11)
- シート状のチタン多孔質体であって、
厚みが0.3mm以下であり、80MPaでの加圧時の圧縮ひずみ量が0.20以下であり、
細孔の直径と容積との関係を示す細孔径分布におけるピーク高さが最も高い第一ピークの半値幅が3.5μm以下であり、前記第一ピークの次にピーク高さが高い第二ピークのピーク高さが、前記第一ピークのピーク高さの10%以下であるチタン多孔質体。 - 前記細孔径分布において、前記第一ピークが現れる位置の細孔の直径が10.0μm以下である請求項1に記載のチタン多孔質体。
- 空隙率が45%以下である請求項1又は2に記載のチタン多孔質体。
- 面積が10000mm2以上である請求項1~3のいずれか一項に記載のチタン多孔質体。
- Ti含有量が98質量%以上である請求項1~4のいずれか一項に記載のチタン多孔質体。
- 前記第二ピークのピーク高さが、前記第一ピークのピーク高さの5%以下である請求項1~5のいずれか一項に記載のチタン多孔質体。
- 成形型の成形面上でチタン粉末を加熱して焼結させ、シート状のチタン多孔質体を製造する方法であって、
10%粒子径D10が5μm以上かつ15μm以下であり、90%粒子径D90が15μm以上かつ25μm以下であるチタン粉末を準備する粉末準備工程と、
前記成形面の外縁部の接着領域に離型層を形成せず、当該接着領域以外の易剥離領域に離型層を形成する離型層形成工程と、
前記離型層形成工程の後、前記成形面上に前記チタン粉末を乾式で堆積させる粉末堆積工程と、
前記粉末堆積工程の後、前記成形面上で前記チタン粉末を950℃以上の最高到達温度に加熱し、前記チタン粉末を焼結させ、焼結体を得る加熱工程と、
前記加熱工程の後、前記成形面上で前記焼結体を冷却し、少なくとも、950℃から800℃までの冷却にかかる時間を1500秒以下とする冷却工程と
を含み、
厚みが0.3mm以下であるチタン多孔質体を製造する、チタン多孔質体の製造方法。 - 面積が10000mm2以上であるチタン多孔質体を製造する、請求項7に記載のチタン多孔質体の製造方法。
- 前記粉末準備工程で準備する前記チタン粉末の平均円形度が0.83以下である請求項7又は8に記載のチタン多孔質体の製造方法。
- 前記成形面を有する成形型の材質が、カーボン、石英、グラファイト、マグネシア(MgO)、カルシア(CaO)、ジルコニア(ZrO2)及びイットリア(Y2O3)からなる群から選択される少なくとも一種を含む、請求項7~9のいずれか一項に記載のチタン多孔質体の製造方法。
- 前記加熱工程で、前記チタン粉末を950℃以上にする時間を、30分~480分とする、請求項7~10のいずれか一項に記載のチタン多孔質体の製造方法。
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JP2002275676A (ja) | 2001-01-15 | 2002-09-25 | Sumitomo Titanium Corp | 多孔質導電板 |
JP2011202202A (ja) | 2010-03-24 | 2011-10-13 | Mitsubishi Materials Corp | 金属焼結体の製造方法及び製造装置 |
JP2014239023A (ja) | 2012-09-07 | 2014-12-18 | 新日鉄住金化学株式会社 | 色素増感太陽電池用集電体およびその材料の製造方法ならびに色素増感太陽電池 |
WO2021171747A1 (ja) * | 2020-02-27 | 2021-09-02 | 東邦チタニウム株式会社 | 多孔質金属体の製造方法及び、多孔質金属体 |
WO2022075038A1 (ja) * | 2020-10-05 | 2022-04-14 | 東邦チタニウム株式会社 | 多孔質金属体の製造方法及び、多孔質金属体 |
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JP2002275676A (ja) | 2001-01-15 | 2002-09-25 | Sumitomo Titanium Corp | 多孔質導電板 |
JP2011202202A (ja) | 2010-03-24 | 2011-10-13 | Mitsubishi Materials Corp | 金属焼結体の製造方法及び製造装置 |
JP2014239023A (ja) | 2012-09-07 | 2014-12-18 | 新日鉄住金化学株式会社 | 色素増感太陽電池用集電体およびその材料の製造方法ならびに色素増感太陽電池 |
WO2021171747A1 (ja) * | 2020-02-27 | 2021-09-02 | 東邦チタニウム株式会社 | 多孔質金属体の製造方法及び、多孔質金属体 |
WO2022075038A1 (ja) * | 2020-10-05 | 2022-04-14 | 東邦チタニウム株式会社 | 多孔質金属体の製造方法及び、多孔質金属体 |
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