KR20210109928A - Porous sintered titanium sheet and method of manufacturing thereof - Google Patents

Abstract

The present invention relates to a porous titanium sintered body and a manufacturing method thereof, and the present invention provides a porous titanium sintered body having a single structure so as to provide a diffusion layer for a water electrolytic positive electrode or an electric current collector with an optimized mass transfer and interfacial resistance value in a water electrolysis cell. The porous titanium sintered body includes a sheet-type titanium sintered body and a plurality of vertically oriented pores existing in the titanium sintered body.

Description

Titanium porous sintered compact and manufacturing method thereof

The present invention relates to a porous titanium sintered body and a method for manufacturing the same, and more particularly, to a porous titanium sintered body applicable as a diffusion layer or a current collector in a water electrolysis device and a method for manufacturing the same.

In general, a PEM water electrolyzer consists of a stack in which several unit cells are stacked, and the unit cells include a titanium bipolar plate, a porous transport layer, an anode catalyst (mainly IrOx), and a cation exchange membrane (proton). exchange memebrane), a carbon-based diffusion layer, and a graphite or titanium separator.

Conventionally, carbon fiber is applied as a diffusion material at the cathode, and titanium paper or mesh is applied as a diffusion material at the anode, or a nano-porous fiber layer using titanium fibers is formed in the form of an electrospinning method to receive PEM power. Disclosed is a configuration applied as a diffuser in a solution device.

In order to secure electrical conductivity (overcoming interfacial resistance) and at the same time optimize water distribution and removal of product gases (hydrogen, oxygen), there is a problem that multiple structures with different porosity (or porosity) sizes must be stacked and used. exist. In order to improve the mass transfer associated with water distribution and product gas removal, the pore size must be large, and the pore size must be small for uniform electrical contact between the laminates. In this regard, optimization of the pore size is required. Generally, in commercial PEM water electrolysis devices, 5 to 7 diffusers with different pore sizes are stacked and used, and a noble metal material such as platinum (Pt) or iridium (Ir) is coated to secure contact electrical conductivity between the laminates. There are structural and economic problems that must be used.

Republic of Korea Patent Publication No. 10-107341 Republic of Korea Patent Publication No. 10-1742724 US Patent Publication No. 2019-0344345

An object of the present invention is to provide a titanium porous sintered body having a single structure as a diffusion layer or an electrical current collector as an anode of a water electrolysis device, etc. The aim is to provide excellent electrical conductivity, optimizing the optimal water distribution and product gas removal within the water electrolysis cell.

In order to achieve the above object, a porous titanium sintered body according to one embodiment of the present invention is a sheet-shaped titanium sintered body; and a plurality of vertically oriented pores that are present in the titanium sintered body.

The pores may have a diameter gradually increasing from one side to the other side according to the sheet shape.

The titanium porous sintered body may have a porosity of 0.36 to 0.487.

The average diameter of the pores may be 10 to 40 μm.

The porous titanium sintered body may have a McMullin Number (NM) of 1.1 to 5.1.

The thickness of the porous titanium sintered body may be 500 μm.

In addition, the method of manufacturing a porous titanium sintered body of titanium according to an embodiment of the present invention comprises the steps of preparing a slurry by mixing a titanium precursor, a solvent, a binder, and a dispersant; dispersing the slurry; Freezing the solvent in the slurry through the first freezing process of the dispersed slurry to prepare a green body; preparing a freeze-formed body from which the frozen solvent is removed through a secondary freezing process for the pre-formed body; and sintering the freeze-formed body.

The titanium precursor may be a titanium hydrogenated powder.

The primary freezing process may be to freeze the solvent in the slurry in a vertical orientation under a temperature gradient condition, and the primary freezing process may be a temperature difference of 50 to 70° C. between the freezing plate and the atmosphere.

According to the present invention as described above, the present invention provides a porous titanium sintered body having a single structure, thereby providing a diffusion layer or an electric current collector for a water electrolytic positive electrode with an optimized mass transfer and interfacial resistance value in the water electrolysis cell. have.

In addition, due to this, there is an effect of enabling efficient operation at a high current density of the water electrolysis cell.

1 shows a schematic diagram of a porous titanium sintered body according to an embodiment of the present invention.
2A to 2C are an upper surface (FIG. 2A to FIG. 2C (a)) and a lower surface (FIG. 2A to 2C (b)) of a porous titanium sintered body according to an embodiment of the present invention. image is shown.
3a and 3b are vertical cross-sectional scanning electron microscope (SEM) images of the porous titanium sintered body according to the embodiment of the present invention and the titanium sintered body according to the comparative example, respectively.
4 shows a scanning electron microscope (SEM) image of a portion of a vertical cross-section of a porous titanium sintered body according to an embodiment of the present invention.
5 shows the pore size distribution results of the porous titanium sintered body according to an embodiment of the present invention.
6 is a view showing a performance analysis result of a water electrolysis cell in which the titanium porous sintered body according to an embodiment of the present invention is applied as a diffusion layer for a positive electrode of the water electrolysis cell.

Hereinafter, the present invention will be described in detail. The terminology used herein is for the purpose of describing the embodiments and is not intended to limit the present invention. As used herein, the singular also includes the plural unless specifically stated otherwise in the phrase.

A porous titanium sintered body according to an embodiment of the present invention includes a sheet-shaped titanium sintered body; and a plurality of vertically oriented pores that are present in the titanium sintered body.

The pores are vertically oriented with respect to the cross section of the sheet-shaped titanium sintered body, and the plurality of pores may form a lamellar structure with respect to the sheet-shaped titanium sintered body by the plurality of vertically oriented pores.

The porous titanium sintered body has one side and the other side of the porous titanium sintered body according to the sheet shape, and the pores have a diameter from one side to the other side of the porous titanium sintered body according to the sheet shape. And, as the diameter gradually increases, the pores may have a tapered shape. More specifically, the pores are formed extending from the lower surface (or surface) of the porous titanium sintered body to the upper surface (or surface), in this case, the pores are formed from the lower surface (or surface) to the upper surface (or surface) The pores may gradually increase in a tapered shape.

1 is a schematic diagram and a partially enlarged view of a porous titanium sintered body according to an embodiment of the present invention, and FIG. 1 is a reference, the titanium porous sintered body 100 is a sheet-shaped titanium sintered body 110 and a titanium sintered body ( It can be confirmed that the plurality of pores 130 present in the vertical orientation are included in 110), and as the plurality of pores 130 are vertically oriented, a vertical lamellar structure is formed in the sheet-shaped titanium sintered body 110 may be doing In addition, referring to the enlarged view (right image) of FIG. 1 , the pore 130 may have a gradually increasing diameter from the lower surface to the upper surface, whereby the pore 130 has a tapered shape. can

The titanium porous sintered body may have a porosity of 0.2 to 0.6.

The average diameter of the pores may be 10 to 100 μm.

The titanium porous sintered body may have a McMullin Number ( N _M ) of 1.1 to 5.1, more preferably 2 to 5.1, and even more preferably 2 or 5.1. The McMullin number may be defined by Equations 1 to 3 below.

[Equation 1]

[Equation 2]

[Equation 3]

In Equations 1 to 3, τ is torsity, ε is porosity, D is diffusion coefficient, i is chemical species, and D _eff is effective diffusion coefficient.

The McMullin number (N _m ) can be obtained through electrochemical analysis as a function of torsion and pores, and it is similar to the representative Bruggeman model expressing diffusion behavior in a porous body, but more accurate effective coefficients can be obtained. In more detail, when the electrolyte in the polycarbonate tank divided into two zones is filled, platinum-coated titanium is used as the counter/working electrode, and a square wave current is applied to place the titanium porous sintered body between the two tanks. It can be obtained from the ratio by measuring the resistance value when it is not located.

In addition, the method of manufacturing a porous titanium sintered body according to an embodiment of the present invention comprises the steps of preparing a slurry by mixing a titanium precursor, a solvent, a binder, and a dispersant; dispersing the slurry; Freezing the solvent in the slurry through the first freeze-casting process of the dispersed slurry to prepare a green body; preparing a freeze-molded body from which the frozen solvent is removed through a secondary freeze-drying process for the green body; and sintering the freeze-formed body.

The titanium precursor may be a titanium hydrogenated (TiH ₂ ) powder, and the titanium precursor may be 15% to 25 vol% with respect to 100 vol% of the slurry.

The titanium hydrogenated (TiH ₂ ) powder may have a particle size (diameter) of 20 to 147 microns (㎛), more preferably 47 to 147 microns (㎛), even more preferably 47 microns (㎛) can be

The solvent acts as a freezing medium, and the solvent may be distilled water (DI water).

The binder may be carboxymethylcellulose, and the binder may be 2 wt% based on 100 wt% of the titanium precursor.

The dispersant may be 1 or 2 or more selected from the group consisting of polyacrylate sodium, BYK190 and Triton X-100, and the dispersant may be 1 wt% based on 100 wt% of the titanium precursor.

The slurry may be dispersed in a homogenizer for 12 hours (h).

In the first freezing process, the solvent of the slurry may be frozen in a vertical orientation under a temperature gradient condition, thereby preparing a preform frozen in the vertical orientation. In addition, in the first freezing process, the diameter of the pores in the porous titanium sintered body manufactured by the above manufacturing method is gradually increased or decreased in the vertical direction by the temperature gradient, so that the pores as a whole may have a tapered shape.

The primary freezing process may be performed on a freezing plate as a freeze caster, and more specifically, the primary freezing process may be performed on a freezing plate provided with a cooling mold. More specifically, the slurry may be dispersed in the cooling mold and cast to have a predetermined shape, and a primary freezing process may be performed in the cooling mold of the freezing plate. The predetermined shape may be a sheet shape.

The cooling mold may be composed of a substrate having a thermal conductivity of 0.5 to 400 W/m·K, preferably composed of a substrate having a thermal conductivity of 0.5 to 15 W/m·K. More specifically, the cooling mold may be formed of a metal substrate having high thermal conductivity, such as copper or stainless steel, or a release film substrate such as PET or KAPTON for improving release characteristics after drying. More specifically, a cooling mold comprising a metal substrate such as copper or stainless steel or a release film substrate such as PET or KAPTON (polyimide film) is provided between the freezing plate and the slurry, and the slurry is disposed on the metal substrate or the release film substrate. The primary freezing process may be performed, and preferably, the metal substrate may be stainless steel, and the release film substrate may be PET. The substrate (cooling mold) prevents the slurry from being rapidly frozen by the freezing plate, thereby allowing the freezing of the solvent in the slurry positioned on the substrate to be made from the lower surface in a vertical orientation.

The first freezing process may be performed in a state in which the slurry is exposed to room temperature, and the room temperature may be 20 to 30 °C. The room temperature may be the temperature of the atmosphere in which the slurry is present, and the first freezing process is preferably performed under conditions in which a temperature gradient (temperature difference) exists between the atmosphere at room temperature and the freezing plate.

The first freezing process forms a temperature gradient formed between the atmosphere at room temperature and the freezing plate, and freezes the solvent in a vertical orientation by the temperature gradient. More specifically, in the first freezing process, the freezing of the solvent in the slurry in the upper direction in contact with the atmosphere from the lower surface of the slurry in contact with the freezing plate is started, and the pores are formed in a vertical orientation to prepare a preform. In addition, as the freezing is sequentially started from the lower surface, it is possible to manufacture a green body formed with different sizes of ice crystals formed by freezing of the solvent.

In the first freezing process, as ice crystals in which the solvent in the slurry are frozen are formed from the lower surface to the upper surface, titanium (Ti) is trapped between the frozen ice crystals. Due to this, it is possible to manufacture in a form in which the size of the pores gradually increases from the lower surface to the upper surface of the pores of the porous titanium sintered body manufactured according to the manufacturing method of the present invention.

The first freezing process may be performed for 2 to 15 minutes (min).

The primary freezing process may be performed at a temperature of -50 to -30 °C of the freezing plate, and the temperature difference (temperature gradient) between the freezing plate and the atmosphere may be maintained at 50 to 75 °C.

The secondary freezing process is to remove the frozen solvent of the preform prepared through the primary freezing process, and more specifically, removes the solvent of the ice crystals formed through the primary freezing process, and removes the solvent. It forms pores in the space and gives the titanium sintered body porous.

The secondary freezing process is performed at -40 ° C. for 1 to 24 hours (h) at a vacuum degree of 0 to 3 Torr.

The step of sintering is to secure mechanical rigidity by sintering the freeze-formed body.

The sintering may be performed at 1100° C. for 2 to 5 hours (h).

Hereinafter, the present invention will be described in more detail through examples. These Examples are for explaining the present invention in more detail, and the scope of the present invention is not limited by these Examples.

Example 1. Preparation of a porous titanium sintered body

TiH ₂ powder (particle size (diameter) 47 micron (㎛)) 15 vol% (based on 100 vol% of the total mixed slurry), TiH ₂ 100 wt% of carboxymethylcellulose as a binder 2 wt%, TiH ₂ 100 Prepare a slurry in which 1 wt% of BYK190 as a dispersant is mixed in a solvent of distilled water (DI water) compared to wt%.

The mixed slurry was dispersed in a homogenizer at a stirring speed of 1,000 rpm for 4 hours (h).

Then, as a cooling mold, a PET (polyethylene terephthalate) substrate (thermal conductivity: 0.5 W/m·K, thickness 18 μm, surface tension 52 mN/m, temperature gradient: 5 ℃) equipped with a frozen plate After preparation, the dispersed slurry is exposed to room temperature (30° C.) and cast on a PET substrate of a freezing plate to prepare a sheet shape. The slurry cast on the PET substrate is heated for 15 minutes (min. ), a preform is prepared by the freezing process (pre-freezing process) at the temperature of the freezing plate at -30 ° C.

Thereafter, the preform is prepared by removing the solvent through a freeze-drying process at -40 ° C. and a vacuum degree of 0 torr for 24 hours (h).

Thereafter, the freeze-molded body is sintered at 1100° C. for 2 hours at a temperature increase rate of 2° C./min to prepare a porous titanium sintered body.

For the titanium porous sintered body prepared in Example 1, the porosity measured by mercury porosimetry was 0.48, the average pore diameter was 40 μm, and the McMullin number (McMullin number) ( Nm) showed a value of 2. The thickness of the sintered body is 500 μm.

Example 2. Preparation of porous titanium sintered body

TiH ₂ powder (particle size (diameter) 47 micron (㎛)) 25 vol% (based on 100 vol% of the total mixed slurry), TiH ₂ 100 wt% of carboxymethylcellulose as a binder, 2 wt%, TiH ₂ 100 Prepare a slurry in which 1 wt% of BYK190 as a dispersant is mixed in a solvent of distilled water (DI water) compared to wt%.

The mixed slurry was dispersed in a homogenizer at a stirring speed of 1,000 rpm for 4 hours (h).

Thereafter, as a cooling mold, a frozen plate equipped with a PET substrate (thermal conductivity: 0.5 W/m·K, thickness 18 μm, surface tension 52 mN/m, temperature gradient: 5° C.) was prepared, and then dispersed. The slurry is prepared in a sheet shape by casting it on a PET substrate of a freezing plate in a state of exposing it to room temperature (30 ° C). A preform is prepared by a freezing process (pre-freezing process) at a temperature of -30 °C.

Thereafter, the preform is prepared by removing the solvent through a freeze-drying process at -40 ° C. and a vacuum degree of 0 torr for 24 hours (h).

Thereafter, the freeze-molded body is sintered at 1100° C. for 2 hours at a temperature increase rate of 2° C./min to prepare a porous titanium sintered body.

For the titanium porous sintered body prepared in Example 2, the porosity measured by mercury porosimetry was 0.36, the average pore diameter was 12 μm, and the McMullin number (McMullin number) ( Nm) showed a value of 5.1. The thickness of the sintered body is 500 μm.

Example 3. Preparation of porous titanium sintered body

TiH ₂ powder (particle size (diameter) 47 micron (㎛)) 15 vol% (based on 100 vol% of the total mixed slurry), TiH ₂ 100 wt% of carboxymethylcellulose as a binder 2 wt%, TiH ₂ 100 Prepare a slurry in which 1 wt% of BYK190 as a dispersant is mixed in a solvent of distilled water (DI water) compared to wt%.

The mixed slurry was dispersed in a homogenizer at a stirring speed of 1,000 rpm for 4 hours (h).

Thereafter, as a cooling mold, a stainless steel substrate (thermal conductivity: 15 W/m·K, thickness 18 μm, surface tension 52 mN/m, temperature gradient: 5° C.) equipped with a freezing plate After preparing a sheet shape by casting the dispersed slurry on a stainless steel substrate of a freezing plate in a state of exposing it to room temperature (30 ° C), the slurry cast on the stainless steel substrate is 30 A preform is prepared by a freezing process (pre-freezing process) at a temperature of -30°C of the freezing plate for minutes (min).

Thereafter, the preform is prepared by removing the solvent through a freeze-drying process at -40°C and a vacuum degree of 0 torr for 24 hours (h).

Thereafter, the freeze-molded body is sintered at 1100° C. for 2 hours at a temperature increase rate of 2° C./min to prepare a porous titanium sintered body.

For the titanium porous sintered body prepared in Example 3, the porosity measured using Mercury porosimetry was 0.7, the average pore diameter was 70 μm, and the McMullin number (McMullin number) ( Nm) showed a value of 1.1. The thickness of the sintered body is 500 μm.

The manufacturing conditions and main physical properties of the prepared sintered body in Examples 1 to 3 are summarized in Tables 1 and 2 below, respectively.

Slurry mixing ratio (based on 100 vol%) frozen plate Ti precursor bookbinder dispersant TiH ₂ powder Carboxymethylcellulose BYK190 Example 1 15 vol% 2 wt%
(Compared to TiH ₂ 100 wt%) 1 wt%
(Compared to TiH ₂ 100 wt%) PET Example 2 25 vol% 2 wt%
(Compared to TiH ₂ 100 wt%) 1 wt%
(Compared to TiH ₂ 100 wt%) PET Example 3 15 vol% 2 wt%
(Compared to TiH ₂ 100 wt%) 1 wt%
(Compared to TiH ₂ 100 wt%) stainless steel

porosity
(porosity) average pore diameter
(pore diameter) McMurley Sue
(McMullin number)(Nm) Titanium porous body sintered body thickness Example 1 0.48 40 μm 2 500 μm Example 2 0.36 12 μm 5.1 500 μm Example 3 0.7 70 μm 1.1 500 μm

comparative example. titanium sintered body

In order to compare with the porous titanium sintered body according to the embodiment of the present invention, the conventional sheet-shaped titanium sintered body (Series 1100; Mott Corporation) that does not perform the 'pre-freezing process' and the 'freeze-drying process' in the embodiment of the present invention (US)) is prepared.

Experimental Example 1. Morphology analysis

A scanning electron microscope (SEM) image (magnification: 500 times) was observed for the upper surface and lower surface of each sintered body prepared in Examples 1 to 3, and it is shown in FIGS. 2a to 2c (Fig. 2a: implementation) Example 1, Figure 2b: Example 2, Figure 2c: Example 3).

2a to 2c, (a) of each figure is a top surface SEM image of each Example sintered body, (b) is a bottom surface SEM image of each example sintered body ((b) (lower surface) image of FIG. 2c is an image observed by rotating 90° with respect to the observation direction of (a) (upper surface) image of FIG. 2c).

2a to 2c, in the preliminary freezing process, it can be seen that the lower surface of the sintered body in contact with the PET substrate (Examples 1 and 2) or the stainless steel substrate (Example 3) of the freezing plate has small pores. In addition, it can be seen that the upper surface of the sintered body exposed to room temperature has a large pore size compared to the lower surface. This is according to the temperature gradient generated between the frozen plate and the ambient temperature in the preform manufacturing (pre-freezing process), and more specifically, the bonding with the freezing plate (PET substrate or stainless steel substrate) is from the lower surface of the sintered body to the upper surface. This is because as the freezing of the solvent in the slurry starts sequentially, the ice crystals formed by the freezing of the solvent have different sizes. After that, the frozen solvent is removed in the freezing process during the manufacture of the freeze-molded body, and the space from which the solvent is removed forms pores. It can be seen that the pore sizes are formed differently, and more specifically, it can be seen that the pore size is a tapered shape in which the pore size gradually increases from the lower surface to the upper surface.

Experimental Example 2. Morphology analysis

For the sintered body prepared in Example 1 and the sintered body prepared in the comparative example, a scanning electron microscope (SEM) image (magnification: 100 times) for a vertical cross-section (cross-section from the upper surface of the sintered body to the lower surface) of the sintered body, respectively It was observed and shown in Fig. 3A (Example 1) and Fig. 3B (Comparative Example), respectively.

Referring to FIG. 3A , it can be seen that the sintered body prepared in Example 1 has a plurality of pores formed in a vertical orientation with respect to a vertical cross section. In contrast, referring to FIG. 3B, the sintered body prepared in Comparative Example is Although this exists, it can be confirmed that the pores formed in the vertical orientation do not exist. This means that according to the 'pre-freezing process' and the 'lyophilization process' in the embodiment of the present invention.

Experimental Example 3. Morphology analysis

With respect to the sintered body prepared in Example 1, a scanning electron microscope (SEM) image (magnification: 500 times) was observed for a portion of a vertical cross-section (cross-section from the upper surface to the lower surface) of the sintered body, which is shown in FIG. did.

Referring to FIG. 4 , the upper image of FIG. 4 is a vertical cross-sectional image of the sintered body manufactured in Example 1, and the lower image of FIG. 4 is an enlarged image indicated by a blue box of the upper image.

Referring to FIG. 4 , it can be confirmed that a plurality of pores present in the sintered body prepared in Example 1 are vertically oriented, and referring to FIG. 2A, a plurality of pores present in the sintered body prepared in Example 1 It can be seen that the pores are vertically oriented and have a tapered shape in which the diameter is gradually increased from the lower surface to the upper surface of the sintered body.

Experimental Example 4. Analysis of pore size

The pore size distribution of the sintered compacts prepared in Examples 1 and 2 was measured through mercury porosimetry, and the measurement results are shown in FIG. 5 .

Referring to FIG. 5 , it can be seen that the sintered bodies prepared in Examples 1 and 2 exhibit a pore distribution of 10 to 100 μm.

Experimental Example 5. Water electrolysis cell performance analysis

The performance of the water electrolysis cell to which the porous titanium sintered body prepared in Example 1 is applied was analyzed by a current-voltage curve, and the analysis result is shown in FIG. 6 .

Analysis of the current-voltage curve was carried out in a water electrolysis cell having an active area ^{of 25 cm 2} under the conditions of 60° C., iridium 2 mg/cm ² as an anode, 1 mg/cm ² carbon-supported platinum as a cathode, and Nafion 115 membrane as a separator. At this time, the titanium porous sintered body of Example 1 was applied as a gas diffusion layer on the anode side.

Referring to FIG. 6 , the case in which the porous titanium sintered body of Example 1 is applied is indicated by (▲), and the case in which the porous titanium sintered body of Example 1 is not applied is indicated by (■).

Oxygen gas generated on the surface of the anode catalyst through the case where the voltage increase at high current density was lower than when the titanium porous sintered body of Example 1 was applied (▲), compared to the case where the titanium porous sintered body of Example 1 was not applied (■) It can be seen that the removal of the electrolyte is smooth and the penetration of the electrolyte (water) is smooth.

On the other hand, the embodiments of the present invention disclosed in the present specification and drawings are merely presented as specific examples to aid understanding, and are not intended to limit the scope of the present invention. It is apparent to those of ordinary skill in the art to which the present invention pertains that other modifications based on the technical idea of the present invention can be implemented in addition to the embodiments presented here.

Above, a specific part of the present invention has been described in detail, for those of ordinary skill in the art, it is clear that this specific description is only a preferred embodiment, and the scope of the present invention is not limited thereby. something to do. Accordingly, the substantial scope of the present invention will be defined by the appended claims and their equivalents.

Claims (10)

sheet-shaped titanium sintered body; and
A porous titanium sintered body that is present in the titanium sintered body and includes a plurality of vertically oriented pores.
The method of claim 1,
The pores are titanium porous sintered body, characterized in that the diameter gradually increases with respect to the other side from one side according to the sheet shape.
The method of claim 1,
The titanium porous sintered body is a porous titanium sintered body, characterized in that the porosity (porosity) of 0.36 to 0.487.
The method of claim 1,
The average diameter of the pores (pore) is a titanium porous sintered body, characterized in that 10 to 40㎛.
The method of claim 1,
The titanium porous sintered body is a porous titanium sintered body, characterized in that McMullin Number (NM) is 1.1 to 5.1.
The method of claim 1,
The porous titanium sintered body has a thickness of 500 μm.
preparing a slurry by mixing a titanium precursor, a solvent, a binder, and a dispersant;
dispersing the slurry;
Freezing the solvent in the slurry through the first freezing process of the dispersed slurry to prepare a green body;
preparing a freeze-formed body from which the frozen solvent is removed through a secondary freezing process for the pre-formed body; and
Including the step of sintering the freeze-formed body
A method for manufacturing a porous titanium sintered body.
8. The method of claim 7,
The titanium precursor is a method of manufacturing a porous titanium sintered body, characterized in that the titanium hydrogenated powder.
8. The method of claim 7,
The first freezing process is a method of manufacturing a porous titanium sintered body, characterized in that the freezing of the solvent in the slurry in a vertical orientation under a temperature gradient condition.
10. The method of claim 9,
The first freezing process is a method of manufacturing a porous titanium sintered body, characterized in that the temperature difference between the freezing plate and the atmosphere is 50 to 70 ℃.

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