CN101569037A - Molding die for fuel cell separator, method of manufacturing fuel cell separator, and fuel cell separator - Google Patents

Abstract

The invention relates to a molding die for a fuel cell separator, a method of manufacturing the fuel cell separator, and the fuel cell separator. The fuel cell separator capable of providing high quality and high productivity with less deformation, warpage, and cracking at its removal from the die by keeping constant a density balance between a gas flow passage groove part area and a surrounding part area on the surface of the separator. When powder-like material is filled in a cavity (50) formed between upper and lower dies (41) and (21) divided into upper and lower inner dies (42) and (22) corresponding to a flow passage groove part (2) and upper and lower outer dies (45) and (25) corresponding to surrounding parts (4), the (upper) lower inner dies ((42))(22) is positioned at a prescribed height (below) above the (upper) lower outer die ((45))(25) so that the compression ratio of the flow passage groove part (2) is equal to the compression ratio of the surrounding part (4). After thecompression molding is completed, the upper and lower outer dies (45) and (25) are projected from the upper and lower inner dies (42) and (22) so that the flow passage groove part (2) can be released in preference to the surrounding parts (4) on both the front and rear surfaces when the die is opened for taking out a molded product.

Description

The finishing die of fuel cell separator, the manufacture method of fuel cell separator and fuel cell separator

Technical field

The present invention relates generally to the manufacture method of fuel cell separator, in more detail, relating to use is that powder is the material of main composition makes fuel cell separator by compression molding finishing die, manufacture method and a fuel cell separator with carbonaceous.

Background technology

In recent years, follow energy consumption to increase, cause that carbon dioxide output increases, and based on the exhausted problem of the fossil resource of oil, in order to solve above-mentioned all problems, the electricity generation system that is made of fuel cell is as clean and new technology efficiently, and practical research is made progress widely.

Especially, in polymer electrolyte fuel cell (PolymerElectrolyte Fuel Cell, below brief note is " the PEFC ") system of electrolyte use amberplex, because of its operating temperature is below 80 ℃, temperature is lower, can easily turn round to stop.Again, the energy efficiency height, therefore, expectation imports home-use cogeneration system, and automobile carries equipment etc.

The basic battery that is used for polymer electrolyte fuel cell is constructed as follows: the dielectric film that is made of amberplex with anode (fuel electrodes) and negative electrode (air pole) clamping, constitute film/assembly of electrode (Membrane Electrode Assembly, below brief note is for " MEA "), with two demarcation strips from this MEA of sandwich.

Form flow passage groove respectively on the demarcation strip surface, the anode (fuel electrodes) that is used for to MEA is supplied with fuel gas such as hydrogen, supplies with the oxidizing gas of oxygen air etc. to negative electrode (air pole).In addition, also be formed for flowing through the refrigerant flow path of cold-producing medium sometimes.Have, demarcation strip has the function as the shield that is used to separate fuel gas and oxidizing gas again.

And, the electric output of fuel cell system necessity, so basic battery serial connection lamination is tens of～and hundreds of, stacked formation.

As the representative characteristic of the necessity of the demarcation strip with above-mentioned such function, be the benchmark occasion with the desired value of USDOE (Department of Energy, below brief note is " DOE "), resistance value is below the 20m Ω cm, the gas transmittance is 2 * 10 ^-6Cc/cm ²Below the secatm, thin-walled, light weight, and in order to popularize to market, it is essential to reduce manufacturing cost significantly.

Have all like this character and demarcation strip cheaply concurrently, initial, thermmohardening type resinoid bond is mixed in the carbonaceous based material is shaped, in non-oxidizing atmosphere, burn till carbonization by long time treatment after the heat hardening with high temperature more than 1000 ℃.

The formed products that obtains with this method is tabular, need be to promoting the circulation of qi body flow passage groove in fact, and the gas entrance hole, there is the very high problem of cost in stacked cut with hole etc.

To this, the resin system binding agent is blended in the good graphite powder material of conductivity, the method of compression molding in the mould that can form flow passage groove shape hole shape in advance, can satisfy all characteristics of demarcation strip necessity, and do not need cut, therefore, as the manufacture method that can realize with low cost, noticeable.

In addition, on the booksly open the manufacture method of fuel cell bipolar plate and formed products such in the 2004-235137 communique the spy, be documented in the pressure forming method that the spy opens powder such in the 2004-22207 communique, the manufacture method of fuel cell separator, and fuel cell separator, be documented in the manufacture method that the spy drives polymer electrolyte fuel cell shaping demarcation strip such in the 2004-235069 communique, above-mentioned document is that people are known.

But in order to obtain high conductivity, the graphite fit rate need be made as more than the 75wt%, and therefore, material flowability is obviously low.As a result, form necessary all shape compression molding occasions, following such problem is arranged at demarcation strip.

The demarcation strip surface is provided with gas flow path slot part and the portion that centers on every side thereof, the density unevenness one of the gas flow path slot part and the portion of centering on.That is, gas flow path slot part material compression ratio height is low around portion's material compression ratio.Therefore, compare with the gas flow path slot part around portion, graphite density is low, and conductivity is low, and the gas transmittance is big.

Figure 1A and Figure 1B represent general demarcation strip one example, and Fig. 2 A and Fig. 2 B represent its sectional view.Figure 1A-Fig. 2 B represents an example of fuel cell separator of the present invention, but is shaped as general shape as demarcation strip, with reference to shape shown, at the general demarcation strip of this explanation.

In order to improve the high conductivity of demarcation strip requirement, importantly, the density of 100% graphite is as far as possible near 2.1g/cm ³If graphite 80wt%, the bulk density of the dusty material of the fit rate of phenolic resins 20wt% is made as 0.65g/cm ³, the goods target density is made as 1.95g/cm ³, then the compression ratio during compression molding is 3.If goods are thick to be 2mm, because of compression ratio is 3, the dusty material that should be filled to mould becomes 6mm.

At this moment, an example will be set at compression ratio 3 occasions around the portion zone as shown in figure 18, the sectional area 86.4mm of the zone that forms the gas flow path slot part during from filling ², according to described compression ratio 3, the sectional area during stroke of a press 4mm compression becomes 22.2mm ², the compression ratio of the gas flow path slot part when being benchmark with the sectional area becomes 3.9, around the portion zone, becomes 30% superfluous compression ratio relatively.The sectional area of gas flow path slot part is big more, and products thickness is thin more, and this phenomenon is remarkable more.

Poor with the described goods cross sectional shape compression ratio that is cause, poor because of the dusty material property that flows, to flow towards the material of transverse direction almost be not basic reason to compression direction relatively.

On the other hand, the demoulding after the article shape of compression molding forms has following such problem.

In order to improve graphite density, press pressure is to be shaped more than about 30MPa.Therefore, the residual high compression stress of mould internal shaping product, behind moulding/demoulding, stress discharges and expands.This phenomenon is called resilience, goods generation buckling deformation, and the gas flow path slot part causes that because of ejection resistance increases fracture is damaged etc. bad.Article shape is a thin-walled, and gas flow path groove depth occasion is especially obvious.

Like this, need keep the high conductivity of demarcation strip requirement on one side, on one side because the article shape thin-walled property, the narrow spacing of gas flow path groove, groove depth increase etc., present situation is in the more and more difficult tendency that is shaped, and wishes to construct the manufacturing technology of compression molding.

Summary of the invention

The present invention puts forward for solving above-mentioned existing in prior technology problem, its purpose is, a kind of finishing die of fuel cell separator is provided, the manufacture method of fuel cell separator and fuel cell separator, using graphite containing ratio height, in the demarcation strip manufacture method of passing through compression molding of the mobile dusty material that lacks, handle by adopting suitable mould and being shaped, make the gas flow path slot part zone on demarcation strip surface and around the density balance homogeneous in portion zone, even take out the also rare distortion of goods from mould, warpage, fracture, the quality height, productivity is good.

In order to achieve the above object, the present invention proposes following technical scheme.

(1) a kind of finishing die of fuel cell separator uses the powder shaped material, and compression molding is provided with the fuel cell separator of the stream slot part and the portion of centering at least at single face, comprising:

Counterdie, with above-mentioned single face subtend, and be divided into the internal mold corresponding with above-mentioned stream slot part and with described around the corresponding external mold of portion;

Action component makes described internal mold and/or external mold advance and retreat.

(2) a kind of finishing die of fuel cell separator uses the powder shaped material, and compression molding is provided with the fuel cell separator that the stream slot part reaches the portion of centering at each face of the table back of the body, comprising:

Patrix, be divided into the last internal mold corresponding with above-mentioned stream slot part and with described around the corresponding last external mold of portion;

Counterdie, be divided into the core insert corresponding with above-mentioned stream slot part and with described around the corresponding following external mold of portion;

A certain side moves with stamping press in patrix and the counterdie;

Framework forms the die cavity periphery between described patrix and the counterdie;

Action component makes the described described relatively internal mold of going up of external mold of going up advance and retreat;

Action component makes described core insert and described external mold down advance and retreat mutually.

(3) a kind of manufacture method of fuel cell separator is used mould, with the compression molding of powder shaped material, makes the fuel cell separator that is provided with the stream slot part and the portion of centering at least at single face;

Counterdie be divided into the internal mold corresponding with above-mentioned stream slot part and with described around the corresponding external mold of portion, when being filled to the powder shaped material in the die cavity that is formed between patrix and the described counterdie, the described relatively external mold of described internal mold is positioned at institute take the altitude top, so that the compression ratio of described stream slot part and the described compression ratio that centers on portion become homogeneous.

(4) a kind of manufacture method of fuel cell separator is used mould, with the compression molding of powder shaped material, makes the fuel cell separator that is provided with the stream slot part and the portion of centering at least at single face;

Mould comprises side's mould and the opposing party's mould, described the opposing party's mould and described single face subtend, and be divided into the internal mold corresponding with above-mentioned stream slot part and with around the corresponding external mold of portion, after shortening shape into by described side's mould and the opposing party's mold pressing, during for the die sinking of taking-up formed products, make the described relatively internal mold of described external mold outstanding, so as described stream slot part than described around the demoulding of elder generation of portion.

(5) a kind of manufacture method of fuel cell separator is used mould, with the compression molding of powder shaped material, makes the fuel cell separator that is provided with the stream slot part and the portion of centering at least at single face;

Mould comprises side's mould and the opposing party's mould, described the opposing party's mould and described single face subtend, and be divided into the internal mold corresponding with above-mentioned stream slot part and with around the corresponding external mold of portion, by described side's mould, the opposing party's mould and the framework that is formed on the die cavity periphery between described two moulds are after the compression molding, during for the die sinking of taking-up formed products, make the described relatively internal mold of described external mold outstanding, so as described stream slot part than described around the demoulding of elder generation of portion;

The demoulding of described stream slot part and described centering under portion's not demoulding state, above-mentioned framework is moved, make the formed products periphery separate with this framework.

(6) a kind of manufacture method of fuel cell separator is used mould, with the compression molding of powder shaped material, is manufactured on the fuel cell separator that each face of the table back of the body is provided with the stream slot part and the portion of centering on;

Patrix be divided into the last internal mold corresponding with above-mentioned stream slot part and with described around the corresponding last external mold of portion, counterdie be divided into the core insert corresponding with above-mentioned stream slot part and with described around the corresponding following external mold of portion, when being filled to the powder shaped material in the die cavity that is formed between the described upper die and lower die, the described relatively external mold down of described core insert is positioned at institute take the altitude top, so that the compression ratio of described stream slot part and the described compression ratio that centers on portion become homogeneous;

During action is contracted in mold pressing, make the described relatively external mold down of the described core insert of described location difference in height decrescence, the mould release simultaneously, described difference in height is separated in fact and is disappeared.

(7) a kind of manufacture method of fuel cell separator is used mould, with the compression molding of powder shaped material, is manufactured on the fuel cell separator that each face of the table back of the body is provided with the stream slot part and the portion of centering on;

Patrix be divided into the last internal mold corresponding with above-mentioned stream slot part and with described around the corresponding last external mold of portion, counterdie be divided into the core insert corresponding with above-mentioned stream slot part and with described around the corresponding following external mold of portion, when being filled to the powder shaped material in the die cavity that is formed between the described upper die and lower die, make outstanding being positioned at above institute's take the altitude of the described relatively external mold down of described core insert earlier, so that the compression ratio of described stream slot part and the described compression ratio that centers on portion become homogeneous;

Then, under described positioning states, above the powder shaped material in being filled to die cavity, described patrix makes the described described relatively external mold of going up of internal mold of going up be projected into quantitatively below of institute, when make described patrix drop to described go up external mold below the described powder shaped material of contact above height the time, along with the described internal mold of going up enters described powder shaped material, make described core insert descend, make the described relatively external mold down of described core insert be positioned at described and go up internal mold relative described to go up external mold equal toward the overhang of below toward the overhang of top.

(8) a kind of manufacture method of fuel cell separator is used mould, with the compression molding of powder shaped material, is manufactured on the fuel cell separator that each face of the table back of the body is provided with the stream slot part and the portion of centering on;

Patrix be divided into the last internal mold corresponding with above-mentioned stream slot part and with described around the corresponding last external mold of portion, counterdie be divided into the core insert corresponding with above-mentioned stream slot part and with described around the corresponding following external mold of portion, after described patrix and counterdie compression molding, during for the die sinking of taking-up formed products, make and describedly go up that external mold and described external mold down are described relatively goes up internal mold and described core insert is outstanding, so as to make described stream slot part that described table carries on the back each face than described around the demoulding of elder generation of portion.

(9) a kind of fuel cell separator is provided with the stream slot part and the portion of centering at single face at least, and the density of material of described stream slot part and the described density of material that centers on portion form homogeneous in fact.

(10) a kind of fuel cell separator, at least be provided with the stream slot part and the portion of centering at single face, counterdie be divided into the internal mold corresponding with above-mentioned stream slot part and with described around the corresponding external mold of portion, make the described relatively external mold of described internal mold be positioned at institute take the altitude top, form die cavity, the powder shaped material is filled in the described die cavity, along with compression section, disappear by making the difference in height of described external mold and internal mold separate, make that the compression ratio and the described compression ratio that centers on portion of described stream slot part are homogeneous, compression molding.

(11) a kind of fuel cell separator, be provided with two sides stream slot part at each face of the table back of the body, the single face stream slot part and the portion of centering on, the density of material of described two sides stream slot part, the density of material of described single face stream slot part and the described density of material that centers on portion form homogeneous in fact.

(12) a kind of fuel cell separator, be provided with two sides stream slot part at each face of the table back of the body, the single face stream slot part and the portion of centering on, counterdie be divided into described around the corresponding following external mold of portion and with described two sides stream slot part and the corresponding core insert of single face stream slot part, make the described relatively external mold down of described core insert be projected into quantitatively top of institute;

Patrix be divided into described around corresponding the last external mold of portion and with described two sides stream slot part and corresponding the last internal mold of single face stream slot part, make described go up internal mold described relatively go up external mold be projected into institute quantitative below;

The powder shaped material is filled in the die cavity that is formed by described counterdie and patrix,,, makes that the compression ratio of described stream slot part and the described compression ratio that centers on portion are homogeneous, compression molding by making outstanding the separating of described core insert and last internal mold disappear along with compression section.

The following describes effect of the present invention.

As mentioned above, finishing die according to fuel cell separator of the present invention, the manufacture method of fuel cell separator and fuel cell separator, in the demarcation strip manufacture method of passing through compression molding of using graphite containing ratio height, the mobile dusty material that lacks, handle by adopting suitable mould and being shaped, make the gas flow path slot part zone on demarcation strip surface and around the density balance homogeneous in portion zone, even take out the also rare distortion warpage fracture of goods from mould, the quality height, productivity is good.

Description of drawings

Figure 1A is the front view of an example of expression fuel cell separator of the present invention, and Figure 1B is its rearview.

Fig. 2 A be II-II along Fig. 1 to the sectional view that obtains, Fig. 2 B is the enlarged drawing of A portion.

Fig. 3 is the longitudinal section of first example of the finishing die of expression fuel cell separator of the present invention.

Fig. 4 is the longitudinal section of major part of the state of the expression die cavity that dusty material is filled to finishing die.

Fig. 5 represents the longitudinal section as the demarcation strip of compression molded product.

Fig. 6 is the longitudinal section of state before the filling that is illustrated in compression molding process in the manufacture method of fuel cell separator of the present invention is adjusted.

Fig. 7 is after the filling adjustment of expression compression molding process, will compress before the longitudinal section of state.

Fig. 8 is the longitudinal section of the compression section intermediateness of expression compression molding process.

Fig. 9 is the longitudinal section of the compression done state of expression compression molding process.

Figure 10 is the longitudinal section that will take out preceding state that takes out the goods process after expression is shaped.

Figure 11 is the longitudinal section that pulls away stream slot part state that takes out the goods process after expression is shaped.

Figure 12 is the longitudinal section that takes out the mould decline state of goods process after expression is shaped.

Figure 13 is the longitudinal section that takes out the die sinking done state of goods process after expression is shaped.

Figure 14 is the figure line of the fuel cell separator quality of expression the present invention manufacturing.

Figure 15 is the state diagram of the fuel cell separator of Figure 14.

Figure 16 is the figure line of the fuel cell separator quality of expression conventional art manufacturing.

Figure 17 is the state diagram of the fuel cell separator of Figure 16.

Figure 18 is the sectional area when representing the filling of compression molding in the past and the ideograph of the sectional area after the compression.

Figure 19 A is the front view of another example of expression fuel cell separator of the present invention, and Figure 19 B is its dorsal view.

Figure 20 is that XX-XX along Figure 19 is to the sectional view that obtains.

Figure 21 A is the A portion enlarged drawing of Figure 20, and Figure 21 B is the B portion enlarged drawing of Figure 20, and Figure 21 C is the C portion enlarged drawing of Figure 20.

Figure 22 is the longitudinal section of second example of the finishing die of expression fuel cell separator of the present invention.

Figure 23 is the longitudinal section of major part of the state of the expression die cavity that dusty material is filled to finishing die.

Figure 24 represents the longitudinal section as the demarcation strip of compression molded product.

Figure 25 is the longitudinal section of state before the filling that is illustrated in compression molding process in the manufacture method of fuel cell separator of the present invention is adjusted.

Figure 26 is the longitudinal section of state before will compressing after the filling adjustment of expression compression molding process.

Figure 27 is the longitudinal section of the compression initial condition of expression compression molding process.

Figure 28 is the longitudinal section of the compression done state of expression compression molding process.

Figure 29 is the longitudinal section of the 3rd example of the finishing die of expression fuel cell separator of the present invention.

Figure 30 is to use the ionization vapour deposition method to form the key diagram of DLC film on the cavity side surface of last inner punch.

Figure 31 is the key diagram that forms the DLC film on the cavity side surface of last outer ram.

Embodiment

Example of the present invention is described with reference to the accompanying drawings.In following example, though to inscape, kind, combination, shape, configuration waits and has done various qualifications relatively,, these only exemplify, and the present invention is not limited thereto.

Figure 1A is the front view of an example of expression fuel cell separator of the present invention, and Figure 1B is its dorsal view, Fig. 2 A be II-II along Fig. 1 to the sectional view that obtains, Fig. 2 B is the enlarged drawing of A portion.

This fuel cell separator 1 is the demarcation strip that is applicable to polymer electrolyte fuel cell system, is provided with stream slot part 2 and surrounds stream slot part 2 portion 4 that centers on every side on two sides (one side at least).

The generating capacity difference of the size fuel cell system of demarcation strip 1, profile is 50～400mm, for example vertical 150mm * horizontal 100mm, thickness 0.5～5mm, for example writing board shape of 2.0mm.

Stream slot part 2 at demarcation strip 1 forms the gas that acts as a fuel, the groove of the stream of oxidizing gas or cooling water (flow passage groove) 3.The degree of depth of flow passage groove 3 is generally thickness of slab about below 1/2 of demarcation strip 1, for example, and 0.5mm.The groove width of flow passage groove 3 is 0.5～5mm, for example 1mm.Spacing between the adjacent flow passages groove 3 is 2mm for example.And, demarcation strip 1 surface surrounded around portion 4 decide in the zone, fine and closely woven configuration forms flow passage groove 3, formation stream slot part 2.

Such flow passage groove 3 is connected with the house steward (manifold) 5 around portion 4 who is formed on demarcation strip 1, makes fuel gas, oxidizing gas or cooling water import by house steward 5 and discharges flow passage groove 3.In Fig. 1, only illustrate 5 liang of systems of flow passage groove 3 and house steward, diagram is omitted the 3rd flow passage groove and the 3rd house steward.

Form groove around portion 4, but this groove being the groove that is used to enclose the appropriate seal material, is not that to become the fluid flowing path groove be flow passage groove 3 yet.In this manual, definition comprises such groove around portion 4.

The moulding material that is used for fuel cell separator 1 of the present invention, mixes the resin system material as main composition with the carbonaceous powder as binding agent.

Because demarcation strip 1 needs high conductivity, as carbonaceous material, preferably has the graphite-structure of high crystalline, Delanium, native graphite, swelling graphite etc. are very suitable, also can mix above-mentioned material with proper ratio.The average grain diameter of powdered graphite is from conductivity, and the material flowability aspect is considered, uses φ 5～100 μ m, be more preferably, φ 10～60 μ m, the ash content in the carbonaceous powder encumber on the demarcation strip 1 electrochemical reaction in abutting connection with catalyst, but make durability low, preferred below 0.5%.

On the other hand, the resin system material that uses as the binding agent of carbonaceous powder can be thermoplasticity or thermosetting resin.From mechanical strength, the durability aspect is considered, is preferably, and uses the thermosetting resin that forms three-dimensional molecular structure.Thermosetting resin can use for example phenol system, epoxy system, and dially phthalate system, unsaturated polyester (UP) system etc., from productivity, the durability aspect considers that be preferably, phenol is resin.

From high conductivity, the high non-pneumatic transmittance and the balance of mechanical strength are considered, the cooperation ratio of above-mentioned powdered graphite and resin system binding agent is powdered graphite 75～95wt%, resin system binding agent 25～5wt%, be preferably, use powdered graphite 82～93wt%, resin system binding agent 18～7wt% cooperates the moulding material of ratio.

Use above-mentioned composite material, the finishing die by following explanation and being shaped is handled (manufacture method) fuel cell separator 1 of the present invention that can be shaped.

Fig. 3 is the longitudinal section of first example of the finishing die that uses in the manufacture method of expression fuel cell separator 1 of the present invention, and for convenience of explanation, shown position is bigger than actual die opening state.In addition, be formed on around the house steward 5 of portion 4 and the superimposed core rod omission that is used to form demarcation strip 1 with through hole.

This finishing die 10 comprises and is located at the fixedly counterdie of lateral mass 20 (low punch) 21, is located at the patrix (upper punch) 41 of mobile lateral mass 40, and framework (mould) 30.Between two moulds 41,21, described framework 30 was the mould of these die cavity 50 peripheries about die cavity 50 was formed on.Framework (mould) 30 also is located at fixedly lateral mass 20, and patrix (upper punch) 41 moves with stamping press with mobile lateral mass 40.

Counterdie (low punch) 21 is divided into core insert (following inner punch) 22 and reaches external mold (following outer ram) 25 formations down.Described core insert 22 is the moulds that are used to form stream slot part 2 region shapes below the demarcation strip 1, and described external mold 25 down is the moulds around portion's 4 region shapes that are used to form below the demarcation strip 1.

In addition, low punch 21 is provided with action component (driver) 24 and action component (driver) 27, described action component 24 makes that inner punch 22 descends outer ram 25 advance and retreat relatively down, can be projected into block 23 and join, described action component 27 makes that outer ram 25 descends inner punch 22 advance and retreat relatively down, can be projected into block 26 and join.

And, make that by driver 24 inner punch 22 descends outer ram 25 outstanding action forces to be set at following size relatively down: when the compression section that stamping press causes finishes, the outstanding degree that disappears of being separated in fact of following inner punch 22.

Have again, low punch 21 is provided with low punch and supplies gas with pipe 28, when die sinking, makes when outer ram 25 descends inner punch 22 to give prominence to relatively down, from the following divisional plane ejection compressed air of inner punch 22 and following outer ram 25, so that make the stream slot part 2 easy demouldings that demarcation strip 1 is following.

Patrix (upper punch) 41 is divided into internal mold (going up inner punch) 42 and goes up external mold (going up outer ram) 45 and constitutes.The described internal mold 42 of going up is the moulds that are used to form stream slot part 2 region shapes above the demarcation strip 1, and the described external mold 45 of going up is the moulds around portion's 4 region shapes that are used to form above the demarcation strip 1.

In addition, upper punch 41 is provided with action component (driver) 47, and it makes that going up outer ram 45 goes up inner punch 42 advance and retreat relatively, can be projected into block 46 and join.

And, make that by driver 47 going up outer ram 45 goes up the stroke that inner punch 42 is given prominence to relatively, and make that by driver 27 outer rams 25 descend inner punch 22 outstanding strokes to be set at than demarcation strip 1 surface relatively down that the depth dimensions of the stream slot part 2 at the back side is big slightly.

Have again, upper punch 41 is provided with upper punch and supplies gas with pipe 48, when die sinking, when make going up outer ram 45 and going up inner punch 42 relatively and give prominence to, from the divisional plane of last inner punch 42 and last outer ram 45 ejection compressed air, so that make the stream slot part 2 easy demouldings above the demarcation strip 1.

Framework (mould) 30 is provided with action component (driver) 32, and it makes advances and retreat above the framework 30, can join from being projected into block 31 than position low above the low punch 21.

Module (die set) function of this finishing die 10 by not having illustrated press arrangement function and being used to keep mould keeps mould 30 to reach inner punch 22 down, following outer ram 25, and last inner punch 42, each mould of last outer ram 45 can move towards the compression molding direction.And, shown in Fig. 3 arrow P, the planar portions with maximum area of relative demarcation strip 1, vertically, by single shaft shaping compression molding.

It is an example that mould shown in Figure 3 constitutes, can be according to the shape of demarcation strip 1, and with mould split position arbitrarily, mould constitutes the number correspondence arbitrarily.

Finishing die 10 of the present invention has the structure that drift is divided into stream slot part 2 zones of demarcation strip 1 and centers on portion 4 zones as mentioned above, therefore, can carry out following such shaping and handle.

In the compression molding of using dusty material, the ratio of the bulk density of the target density of compression molded product and material is made as compression ratio, decision is to the material charging quantity of die cavity 50.Especially, the material occasion of mobile difference, the deviation state of formed products partial compression ratio becomes density variation with keeping intact, causes that quality is low significantly.The placement method of the compression punching formation of dusty material generally with above the mould as benchmark, get rid of the superfluous material that drops into, suppress the deviation of charging quantity.

Fig. 4 is the longitudinal section of major part of the state of the expression die cavity 50 that dusty material is filled to finishing die 10.

Fig. 5 represents the longitudinal section as the demarcation strip 1 of compression molded product.The sectional position of Fig. 4 and Fig. 5 is identical.

In the manufacturing of using finishing die 10 of the present invention is handled, be that compression ratio is assumed at 3 o'clock with the ratio of the bulk density of target density and dusty material, products thickness is made as Tmm, and the sectional area around portion 4 zones of demarcation strip 1 is made as S _Out, make the mould 30 3 * Tmm that above low punch 21, rises, be provided with and have 3 * S _OutThe space of sectional area, the filling suitable material.

At this moment, outer ram 25 is top smooth owing to descending, ideally filler.

To this, the sectional area in stream slot part 2 zones of demarcation strip 1 is made as S _In, if make the mould 30 3 * Tmm that rises, the suitable material of sectional area that is used to form the module convex part of flow passage groove 3 becomes residue, the material that is filled to stream slot part 2 zones surpasses 3 * S _In

So, in the manufacturing of using finishing die 10 of the present invention is handled,, make the following inner punch 22 that is used to form flow passage groove 3 institute of rising decide the h size in order to prevent described surplus material filling, that is,, can be adjusted into 3 * S by minimizing material filling space h size part _InSectional area.

And, can adjust this h size arbitrarily, relatively as S around portion 4 _OutThe density of portion can be controlled the S as stream slot part 2 relatively _InThe density of portion.Can make and if necessary, also can increase and decrease the density of stream slot part 2 relatively around the density of portion 4 by both sides' density homogeneous.

Fig. 6-Fig. 9 is illustrated in the longitudinal section of compression molding process in the manufacture method of the fuel cell separator that uses finishing die 10 of the present invention, wherein, Fig. 6 is a state before filling is adjusted, Fig. 7 state when to be that filling is adjusted will compress, Fig. 8 is the compression section intermediateness, and Fig. 9 represents to compress done state.

In order to reduce the density variation of demarcation strip 1 integral body, in compression section, make the compression speed in stream slot part 2 zones that the material charging quantity is few reach the compression speed equalization that centers on portion 4 zones, promptly, begin roughly to finish simultaneously from compression by making to the operation that compression finishes, can eliminate the mass deviation in both sides zone 2,4.

Specifically, be preferably, pass through air pressure, oil pressure, spring, the actuating force of drivers such as motor 24 makes that with the confining force littler than the compression stress of upper punch 41 sides inner punch 22 floats down, the state that maintenance can descend according to the compression stress of upper punch 41 sides, perhaps with than upper punch 41 sides slightly jogging speed descend.As a result, even the few zone of charging quantity is the short zone of compression stroke, compression speed can slow down.

Fig. 8 represents the compressed intermediateness of dusty material.Although following inner punch 22 descends, do not arrive the compression end position, for not reaching the intermediateness of target density.

Fig. 9 represents to compress done state.Following inner punch 22 is in the falling-threshold position because of the forcing press compression stress bigger than the maintenance climbing power of driver 24, with following outer ram 25 identical faces states or institute's allocation, shaping demarcation strip 1.

Figure 10-Figure 13 is illustrated in the back that is shaped in the manufacture method of the fuel cell separator that uses finishing die 10 of the present invention and takes out the longitudinal section of goods process, wherein, Figure 10 represents to take out preceding state, Figure 11 represents to pull away stream slot part state, Figure 12 represents mould decline state, and Figure 13 represents the die sinking done state.

Figure 10 represents to take out the preceding state of demarcation strip.At this moment, by air pressure, oil pressure, spring, the actuating force of drivers such as motor 27,47 to following outer ram 25 and last outer ram 45, gives power in advance towards the direction of releasing demarcation strip 1.

The condition of this release power is: the power of the top pressure head of specific pressure machine (diagram is omitted) pushing demarcation strip 1 is little.Be made as d if will go up the degree of depth of the flow passage groove 3 of inner punch 42 formation ₁, the stroke of then going up outer ram 45 is set at and d ₁Identical or d ₁More than.Equally, if will descend the degree of depth of the flow passage groove 3 of inner punch 22 formation to be made as d ₂, then descend the stroke of outer ram 25 to be set at and d ₂Identical or d ₂More than.

Figure 11 represents that the mould of the stream slot part 2 of release property difference extracts state from demarcation strip 1.At last outer ram 45, following outer ram 25 is released under the power effect state towards demarcation strip 1, if the top pressure head rises, then going up inner punch 42 above outer rams 45 is supporting point, and same, following inner punch 22 following outer rams 25 are supporting point, from demarcation strip 1 knockout press effect.Total (the d of flow passage groove 3 ladders of top pressure head rising demarcation strip 1 upper and lower surface ₁+ d ₂) time, the flow passage groove 3 of demarcation strip 1 upper and lower surface is from moulding/demoulding.

After when this process begins, just having begun the demoulding, under air-tight state, make stream slot part 2 demouldings of demarcation strip 1, therefore, almost can not expect that the atmosphere of mould surface and mould cut-off rule imports, and becomes decompression state from demarcation strip 1.So, from divisional plane ejection compressed air, the successfully demoulding of each inner punch 22,42 and each outer ram 25,45.

Figure 12 represents to be used to form the mould 30 decline states of the peripheral shape of demarcation strip 1.Demarcation strip 1 inside that has just formed by compression molding produces big compression stress.When taking out demarcation strip 1, mould breaks away from simultaneously, and internal stress discharges, and produces resilience, and demarcation strip 1 expands.Springback capacity is because of material, forming temperature, and differences such as compression stress produce 0.2～0.8% approximately, and the demarcation strip of vertical 150mm * horizontal 100mm is the above swell increment of 1mm.

As shown in figure 12, under last outer ram 45 and following outer ram 25 pushing demarcation strips 1 state, extract mould 30, internal stress discharges towards the in-plane (diagram transverse direction) of demarcation strip 1.If before extracting mould 30, make all upper punchs 41 rise, then can not lose release place to the internal stress that outer circumferential side discharges, the central portion of demarcation strip 1 is deformed into convex.

Figure 13 represents that upper punch 41 pulls away demarcation strip 1 fully, can easily take out state.As the method that makes the upper punch 41 and demarcation strip 1 demoulding reliably, can so that the operate time of the ajutage of upper punch 41 sides longer slightly than low punch 21 sides.

Embodiment 1

Below, specifying and use finishing die of the present invention, the shaping of the fuel cell by manufacture method compression molding of the present invention is handled.But the present invention is not limited to these embodiment.

(1) shape of demarcation strip 1, vertical 150mm, horizontal 100mm, thickness 2mm (or 2.5mm), the width 1mm of gas flow path groove 3, degree of depth 0.5mm, spacing 2mm, 12 row are configured in the surface, the central authorities at the back side.

(2) dusty material uses ash content 0.15%, the spherical natural graphite of average grain diameter φ 30 μ m (or same Delanium) 80wt%, and the resin system binding agent is the mixture of bakelite type phenol 20wt%.Bulk density is 0.65g/cm ³

(3) the compression molding device uses 150 tons of hydraulic presses of upper punch decline type.Last inner punch 42 directly is connected with the hydraulic press upside is dull and stereotyped, other mould 30, last outer ram 45, following outer ram 25, following inner punch 22 is by being located at moving as the hydraulic oil cylinder driving of drive source with oil pressure in the module, and actuating length is by the end of travel block decision that is located in the module.

In addition, for the operate time of each mould, by the position of linear measurement device detection upper punch stroke, by with the program control of its voltage signal as triggering, switch oil pressure pump, each moves control.

(4) with density 1.95g/cm ³As target, to obtain the performance as demarcation strip 1, the bulk density of dusty material is 0.65g/cm ³, therefore, the benchmark compression ratio is made as 3.Therefore, the material charging quantity that centers on portion 4 zones of demarcation strip 1 is set at 6mm according to 2mm * 3.Stream slot part 2 zone needs to reduce 1.8mm, so that make the ratio of space sectional area of the sectional area of demarcation strip 1 and die cavity 50 become 1: 3, therefore, be used to form the following inner punch 22 rising 1.8mm of the mould in stream slot part 2 zones, that is, according to 6mm-1.8mm, charging quantity is set at 4.2mm.

(5) in order to improve flowability, the mould temperature is heated to 60 ℃,, compressed for 15 seconds with 125 tons by above-mentioned hydraulic press device.

(6) after compression molding finishes, open oil pressure pump, outer ram 25 moved towards the direction of releasing demarcation strip 1 under feasible upward outer ram 45 reached.Simultaneously, the cutting part from each outer ram 45,25 and each inner punch 42,22 sprays demoulding air-flow.

Keep this state,, then set the last outer ram 45 of the actuating length of 0.5mm respectively if make forcing press top pressure head rising 1mm, under the state of following outer ram 24 clamping demarcation strips 1, last inner punch 42, following inner punch 22 is extracted from the stream slot part 2 of demarcation strip 1.

After this,, make mould 30 descend, extract demarcation strip 1 peripheral part at once by oil pressure actuated.After this, by making the top pressure head rise, take out demarcation strip 1 and finish.

(7) Figure 14 is illustrated in inner punch 42, and last outer ram 45 is provided with die cavity 30 pressure sensors, and the material pressure that produces in the compression molding operation changes figure line.Pressure state approximate equality around portion 4 zones and stream slot part 2 zones.In the density of each regional formed thereby, be 1.97g/cm around portion ³, the stream slot part is 1.95g/cm ³, the quality equalization.

Figure 15 is the stream slot part 2 bight enlarged drawings of demarcation strip 1.The mould form accuracy is transferred well, can successfully take out goods.

(8) on the other hand, Figure 16 is the pressure variation of expression conventional art compression molding occasion.The pressure in stream slot part zone rises big, and the pressure that centers on the portion zone rises and is about 1/2～1/3, and deviation is very big.As a result, in the density of each regional formed thereby, be 1.79g/cm around portion ³, the stream slot part is 1.98g/cm ³, lowly remarkable around the density of portion.

Figure 17 is the stream slot part bight enlarged drawing of demarcation strip 1.When taking out demarcation strip, produce very big ejection resistance, the bight takes place damaged.

Figure 19 A is the front view of the each several part of expression fuel cell separator 1 shown in Figure 1, Figure 19 B is its dorsal view, Figure 20 be XX-XX along Figure 19 to the sectional view that obtains, Figure 21 A is the A portion enlarged drawing of Figure 20, Figure 21 B is the B portion enlarged drawing of Figure 20, and Figure 21 C is the C portion enlarged drawing of Figure 20.

See the cross section of fuel cell separator 1, its major part constitutes by stream slot part 2 with around portion 4 shown in Fig. 2 A.And stream slot part 2 is provided with flow passage groove 3 at each face of the table back of the body shown in Fig. 2 B.

, in each flow passage groove 3 part that links to each other with house steward 5, shown in Figure 20 and Figure 21 A-21C, only form flow passage groove 3 at single face, there is the zone 6 that does not have flow passage groove 3 in the face of opposition side.That is, see the cross section of fuel cell separator 1 in detail, be included in the two sides stream slot part 2 that the two sides is provided with flow passage groove 3, only be provided with the single face stream slot part 6 of flow passage groove 3, surround stream slot part 2,6 portion 4 that centers on every side at single face.The opposing face of single face stream slot part 6 is by constituting around portion 4.

And single face stream slot part 6 shown in Figure 21 B of the B portion of amplifying Figure 20, only is provided with the single face stream slot part 6 of flow passage groove 3 below, and shown in Figure 21 C of the C portion of amplifying Figure 20, only is provided with the single face stream slot part 6 of flow passage groove 3 in the above.

This single face stream slot part 6, in finishing die 10 shown in Figure 3, with two sides stream slot part 2, the zone that is dispensed on down inner punch 22 and goes up inner punch 42.Finishing die 10 occasions shown in Figure 3, low punch 21 is provided with action component (driver) 24, makes that inner punch 22 descends outer ram 25 advance and retreat relatively down, can be projected into block 23 and join, and upper punch 41 is not provided with such action component (driver).Therefore, before filling adjustment shown in Figure 6, before will compressing after filling adjustment shown in Figure 7, in the middle of the compression section shown in Figure 8, after compression end shown in Figure 9, last inner punch 42 reaches the position relationship that goes up outer ram 45.

As shown in Figure 4, make inner punch 22 down descend relatively outer ram 25 rise fixed h size, make the material filling space reduce h size part, carry out the sectional area S that centers on portion 4 zones of demarcation strip 1 _OutSectional area S with stream slot part 2 zones _InAdjustment, as shown in figure 14, the pressure state approximate equality realizes the density homogeneity.

But as mentioned above, fuel cell separator 1 removes two sides stream slot part 2 and around portion 4, single face stream slot part 6 that only is provided with flow passage groove 3 below and the single face stream slot part 6 that only is provided with flow passage groove 3 is in the above arranged.Wherein, the single face stream slot part 6 that only is provided with flow passage groove 3 below and around it around between the portion 4, adjust the sectional area of h size part in advance.In contrast, the single face stream slot part 6 that only is provided with flow passage groove 3 in the above and around it around between the portion 4, do not carry out such sectional area adjustment, in addition, do not carry out compression section.

With reference to Figure 18, as mentioned above, will be set at compression ratio 3 occasions, the sectional area 86.4mm of the zone of stream slot part (two sides stream slot part) 2 during from filling around the zone of portion 4 ², with compression ratio 3, during stroke of a press 4mm compression, sectional area becomes 22.2mm ², the compression ratio of the stream slot part 2 with sectional area during as benchmark is 3.9, around portion 4 zones, becomes 30% superfluous compression ratio relatively.Equally, the zone of single face stream slot part 6 becomes 10% superfluous compression ratio relatively around portion 4 zones.

Promptly, finishing die 10 occasions shown in Figure 3, side below demarcation strip 1, relatively around portion 4 zones, the zone of the single face stream slot part 6 different with its compression ratio, the zone of two sides stream slot part 2 together, adjust the sectional area of h size part in advance, in contrast, at the upper face side of demarcation strip 1, the sectional area adjustment is not carried out in the zone of the not only zone of single face stream slot part 6, and two sides stream slot part 2 yet.

So in compression initial stage (during the compression beginning), side and upper face side two sides below demarcation strip 1 carry out necessary sectional area adjustment equably, can improve the density homogeneity of demarcation strip 1, the following describes such finishing die.

Figure 22 is the longitudinal section of second example of the finishing die that uses in the manufacture method of expression fuel cell separator 1 of the present invention, and for convenience of explanation, shown position is bigger than actual die opening state.In addition, be formed on around the house steward 5 of portion 4 and the superimposed core rod omission that is used to form demarcation strip 1 with through hole.

This finishing die 110 comprises and is located at the fixedly counterdie of lateral mass 120 (low punch) 121, is located at the patrix (upper punch) 141 of mobile lateral mass 140, and framework (mould) 130.Between two moulds 141,121, described framework 130 was the mould of these die cavity 150 peripheries about die cavity 150 was formed on.Framework (mould) 130 also is located at fixedly lateral mass 120, and patrix (upper punch) 141 moves with stamping press with mobile lateral mass 140.

Counterdie (low punch) 121 is divided into core insert (following inner punch) 122 and reaches external mold (following outer ram) 125 formations down.Described core insert 122 is to be used to form the two sides stream slot part 2 of demarcation strip 1 and the mould of following stream slot part 2,6 region shapes among the single face stream slot part 6, and described down external mold 125 is the moulds around portion's 4 region shapes that are used to form below the demarcation strip 1.

In addition, low punch 121 is provided with action component (driver) 124 and action component (driver) 127, described action component 124 makes that inner punch 122 descends outer ram 125 advance and retreat relatively down, can be projected into block 123 and join, described action component 127 makes that outer ram 125 descends inner punch 122 advance and retreat relatively down, can be projected into block 126 and join.

And, make that by driver 124 inner punch 122 descends outer ram 125 outstanding action forces to be set at following size relatively down: when the compression section that stamping press causes finishes, the outstanding degree that disappears of being separated in fact of following inner punch 122.

Have, low punch 121 is provided with low punch and supplies gas with pipe 128, when die sinking again, make when outer ram 125 descends inner punch 122 to give prominence to relatively down, from the following divisional plane ejection compressed air of inner punch 122 and following outer ram 125, so that make stream slot part 2, the 6 easy demouldings that demarcation strip 1 is following.

Patrix (upper punch) 141 is divided into internal mold (going up inner punch) 142 and goes up external mold (going up outer ram) 145 and constitutes.Described upward internal mold 142 is to be used to form the two sides stream slot part 2 of demarcation strip 1 and the mould of top stream slot part 2,6 region shapes among the single face stream slot part 6, and the described external mold 145 of going up is the moulds around portion's 4 region shapes that are used to form above the demarcation strip 1.

In addition, upper punch 141 is provided with action component (driver) 144 and action component (driver) 147, described action component 144 makes that going up inner punch 142 goes up outer ram 145 advance and retreat relatively, can be projected into block 143 and join, described action component 147 makes that going up outer ram 145 goes up inner punch 142 advance and retreat relatively, can be projected into block 146 and join.

And, go up outer ram 145 outstanding action forces relatively by driver 144 feasible upward inner punches 142 and be set at following size: when the compression section that stamping press causes finishes, the outstanding degree that disappears of being separated in fact of last inner punch 142.

In addition, make that by driver 147 going up outer ram 145 goes up the stroke that inner punch 142 is given prominence to relatively, and the strokes that make outer rams 125 down descend inner punch 122 to give prominence to relatively by driver 127 are set at than demarcation strip 1 surface, and the degree of depth essence same size of the stream slot part 2,6 at the back side is big slightly.

Have, upper punch 141 is provided with upper punch and supplies gas with pipe 148, when die sinking again, when make going up outer ram 145 and going up inner punch 142 relatively and give prominence to, from the divisional plane of last inner punch 142 and last outer ram 145 ejection compressed air, so that make stream slot part 2, the 6 easy demouldings above the demarcation strip 1.

Framework (mould) 130 is provided with action component (driver) 132, and it makes advances and retreat above the framework 130, can join from being projected into block 131 than position low above the low punch 121.

The module function of this finishing die 110 by not having illustrated press arrangement function and being used to keep mould keeps mould 130 to reach inner punch 122 down, following outer ram 125, and last inner punch 142, each mould of last outer ram 145 can move towards the compression molding direction.And, shown in Figure 22 arrow P, the planar portions with maximum area of relative demarcation strip 1, vertically, by single shaft shaping compression molding.

It is an example that mould shown in Figure 22 constitutes, according to the degree of depth of the flow passage groove 3 of two sides stream slot part 2 that is formed on demarcation strip 1 and single face stream slot part 6, and width, the spacing difference also can be omitted low punch 121, the activities of upper punch 141.In addition, can be according to the shape of demarcation strip 1, with mould split position arbitrarily, mould constitutes the number correspondence arbitrarily.

Finishing die 110 of the present invention has stream slot part 2 zones, two sides that drift is divided into demarcation strip 1 as mentioned above, and single face stream slot part 6 zones reach the structure around portion 4 zones, therefore, can carry out following such shaping and handle.

In the compression molding of using dusty material, the ratio of the bulk density of the target density of compression molded product and material is made as compression ratio, decision is to the material charging quantity of die cavity 150.Especially, the material occasion of mobile difference, the deviation state of formed products partial compression ratio becomes density variation with keeping intact, causes that quality is low significantly.The placement method of the compression punching formation of dusty material generally with above the mould as benchmark, get rid of the superfluous material that drops into, suppress the deviation of charging quantity.

Figure 23 is the longitudinal section of major part of the state of the expression die cavity 150 that dusty material is filled to finishing die 110.

Figure 24 represents the longitudinal section as the demarcation strip 1 of compression molded product.The sectional position of Figure 23 and Figure 24 is identical.

In the manufacturing of using finishing die 110 of the present invention is handled, be that compression ratio is assumed at 3 o'clock with the ratio of the bulk density of target density and dusty material, products thickness is made as Tmm, and the sectional area around portion 4 zones of demarcation strip 1 is made as S _Out, make the mould 130 3 * Tmm that above low punch 121, rises, be provided with and have 3 * S _OutThe space of sectional area, the filling suitable material.

At this moment, outer ram 125 is top smooth owing to descending, ideally filler.

In contrast, the sectional area in stream slot part 2 zones, two sides of demarcation strip 1 and single face stream slot part 6 zones is made as S _In, if make the mould 130 3 * Tmm that rises, the suitable material of sectional area that is used to form the module convex part of flow passage groove 3 becomes residue, the material that is filled to stream slot part 2 zones, two sides and single face stream slot part 6 zones surpasses 3 * S _In

So, in the manufacturing of using finishing die 110 of the present invention is handled,, reduce the space of the flow passage groove 3 that forms upper punch 141 sides and low punch 121 sides as described as follows in order to prevent described surplus material filling, therefore, can be adjusted into 3 * S _InSectional area.

That is, the last inner punch 142 that make to form the upper punch side flow passage groove 3 of demarcation strip 1 form relatively the upper punch gussets around the last outer ram 145 of portion 4 give prominence to (decline) fixed Hu size part, minimizing is equivalent to the material charging quantity of upper punch side flow passage groove 3.

Equally, the following inner punch 122 that make to form the low punch side flow passage groove 3 of demarcation strip 1 form relatively the low punch gussets around the following outer ram 125 outstanding (risings) of portion 4 fixed Hl size part, minimizing is equivalent to the material charging quantity of low punch side flow passage groove 3.

Have again, by making Hu size part of the last inner punch 142 outstanding (decline) that forms upper punch side flow passage groove 3 be added in down on outstanding (rising) part of inner punch 122, make space minimizing (Hu+Hl) size parts of flow passage groove 3 formation of upper punch 141 sides and low punch 121 sides.

And, can adjust this (Hu+Hl) size arbitrarily, relatively as S around portion 4 _OutThe density of portion can be controlled the S as stream slot part 2,6 relatively _InThe density of portion.Can make and if necessary, also can increase and decrease the density of stream slot part 2,6 relatively around the density of portion 4 by both sides' density homogeneous.

Figure 25-Figure 28 is illustrated in the longitudinal section of compression molding process in the manufacture method of the fuel cell separator that uses finishing die 110 of the present invention, wherein, Figure 25 is a state before filling is adjusted, Figure 26 state when to be that filling is adjusted will compress, Figure 27 is the compression A-stage, and Figure 28 represents to compress done state.

In order to reduce the density variation of demarcation strip 1 integral body, in compression section, make the stream slot part 2 that the material charging quantity is few, the compression speed in 6 zones reaches the compression speed equalization around portion 4 zones, promptly, begin roughly to finish simultaneously from compression by making, can eliminate zone 2,6 and regional 4 both sides' mass deviation to the operation that compression finishes.

Specifically, be preferably, pass through air pressure, oil pressure, spring, the actuating force of drivers such as motor 124 makes that with the confining force littler than the compression stress of upper punch inner punch 122 floats down, the state that maintenance can descend according to the compression stress of upper punch 141 sides, perhaps with than upper punch 141 sides slightly jogging speed descend.

Equally, be preferably, pass through air pressure, oil pressure, spring, the actuating force of drivers such as motor 144 makes that with the confining force littler than the compression stress of upper punch going up inner punch 142 floats along compression direction, the state that maintenance can be risen relatively according to the compression stress of upper punch 141 sides, perhaps with relative rising of the roughly the same speed of the decrease speed of following inner punch 122.

As a result, even the few zone of charging quantity is the short zone of compression stroke, compression speed can slow down.

State when Figure 26 represents that filling is adjusted and will compress is guaranteed no matter the cross sectional shape of demarcation strip 1 can be realized the charging quantity of impartial compression ratio at die cavity 150.At this moment, following inner punch 122 is in and descends (Hu+Hl) position of size part of outer ram 125 outstanding (rising) relatively.On the other hand, last inner punch 142 is in the position of going up outer ram 145 outstanding (decline) Hu size parts relatively.And upper punch 141 will be in the time will compressing, and the lower end of last inner punch 142 is in and is filled in the height that the dusty material in the die cavity 150 joins above.

Figure 27 represents to compress A-stage.At this, illustrate from state shown in Figure 26 to move on to state shown in Figure 27.That is, when this moves, because the compression stress of upper punch 141 sides, drop to below the last outer ram 145 and be filled in the height that the dusty material in the die cavity 150 joins above.At this moment, keep the actuating force of driver 144, reduce the actuating force of driver 124, last inner punch 142 makes that along with the pushing force that the dusty material that will be filled in the die cavity 150 pushes toward the below inner punch 122 descends down.

Like this, as shown in figure 27, last inner punch 142 is in the position of outstanding (declines) Hu size part above the dusty material from be filled in die cavity 150, and on the other hand, following inner punch 122 is in the position that (rising) Hl size part is given prominence in dusty material bottom surface from be filled in die cavity 150.

That is, be filled in the state (going up the overhang Hu that inner punch 142 is gone up outer ram 145 relatively) of the upper punch 141 of the dusty material upper face side in the die cavity 150 and be filled in die cavity 150 in dusty material below the mutual unanimity of state (the following inner punch 122 relative overhang Hl of outer rams 125 down) of low punch 121 of side.

Then, from this state, because of the compression stress of upper punch 141 sides, the compression section of start powder material in fact.In this compression section, directly be subjected to the compression stress compression molding of upper punch around portion 4 zones, on the other hand, the following inner punch 122 in stream slot part 2,6 zones descends (retreating), and last inner punch 142 rises relatively, compression molding.

Figure 28 represents to compress done state.Following inner punch 122 is in the falling-threshold position because of the forcing press compression stress of the upper punch bigger than the confining force of driver 124, that is, be in and following outer ram 125 identical faces states (or institute's allocation).In addition, last inner punch 142 is in the rising extreme position because of the forcing press compression stress of the upper punch bigger than the confining force of driver 144, that is, be in and last outer ram 145 identical faces states (or institute's allocation).And demarcation strip 1 is shaped.

In the manufacturing of using finishing die 110 of the present invention was handled, back taking-up goods process was identical with the first example occasion about being shaped, and diagram and explanation thereof are omitted.That is, take out in the goods process after shaping, state is extracted stream slot part state with reference to Figure 11 with reference to Figure 10 before will taking out, and mould decline state is with reference to Figure 12, and the die sinking done state is with reference to Figure 13.If each symbol to Figure 10-Figure 13 adds 100, then be more readily understood.

Use the finishing die 110 of described second example to make fuel cell separator 1 occasion, make fuel cell separator 1 occasion with the finishing die 10 that uses described first example and compare, can further improve the density homogeneity of demarcation strip 1.

Embodiment 2

Below, specifying the finishing die 110 that uses this second example, the shaping of the fuel cell separator by manufacture method compression molding of the present invention is handled.But the present invention is not limited to these embodiment.

(1) shape of demarcation strip 1, vertical 150mm, horizontal 100mm, thickness 2mm (or 2.5mm), the width 1mm of gas flow path groove 3, degree of depth 0.5mm, spacing 2mm, 12 row are configured in the surface, the central authorities at the back side.

(2) dusty material uses ash content 0.15%, the spherical natural graphite of average grain diameter φ 30 μ m (or same Delanium) 80wt%, and the resin system binding agent is the mixture of bakelite type phenol 20wt%.Bulk density is 0.65g/cm ³

(3) the compression molding device uses 400 tons of hydraulic presses of upper punch decline type.Mould 130, last outer ram 145, last inner punch 142, following outer ram 125, following inner punch 122 is by being located at moving as the hydraulic oil cylinder driving of drive source with oil pressure in the module, and actuating length is by the end of travel block decision that is located in the module.

In addition, for the operate time of each mould, by the position of linear measurement device detection upper punch stroke, by with the program control of its voltage signal as triggering, switch oil pressure pump, each moves control.

(4) with density 1.95g/cm ³As target, to obtain the performance as demarcation strip 1, the bulk density of dusty material is 0.65g/cm ³, therefore, the benchmark compression ratio is made as 3.Therefore, the material charging quantity that centers on portion 4 zones of demarcation strip 1 is set at 6mm according to 2mm * 3.

At stream slot part 2,6 zones, upper face side stream slot part 2 needs to reduce 0.9mm, following effluent road slot part 2 also needs to reduce 0.9mm, so that make the ratio of space sectional area of the sectional area of demarcation strip 1 and die cavity 150 become 1: 3, therefore, the overhang (slippage) that last inner punch 142 is gone up outer ram 145 relatively is set at 0.9mm, on the other hand, following inner punch 122 descends the overhang (ascending amount) of outer ram 125 also to be set at 0.9mm relatively.

And, add the overhang 0.9mm of inner punch 142 on the above, make that inner punch 122 adds up to outstanding 1.8mm down, the material charging quantity in stream slot part 2 zones is set at 4.2mm according to 6mm-1.8mm.

(5) in order to improve flowability, the mould temperature is heated to 60 ℃,, compressed for 15 seconds with 125 tons by above-mentioned hydraulic press device.

(6) after compression molding finishes, open oil pressure pump, outer ram 125 moved towards the direction of releasing demarcation strip 1 under feasible upward outer ram 145 reached.Simultaneously, the cutting part from each outer ram 145,125 and each inner punch 142,122 sprays demoulding air-flow.

Keep this state,, then set the last outer ram 145 of the actuating length of 0.5mm respectively if make forcing press top pressure head rising 1mm, under the state of following outer ram 124 clamping demarcation strips 1, last inner punch 142, following inner punch 122 is extracted from the stream slot part 2 of demarcation strip 1.

After this,, make mould 130 descend, extract demarcation strip 1 peripheral part at once by oil pressure actuated.After this, by making the top pressure head rise, take out demarcation strip 1 and finish.

(7) the present embodiment occasion obtains cavity pressure variation as shown in Figure 14 also similarly to Example 1, around the pressure state approximate equality in portion 4 zones and stream slot part 2,6 zones.In the density of each regional formed thereby, be 1.97g/cm around portion ³, the stream slot part is 1.95g/cm ³, the quality equalization.

In addition, can obtain article shape as shown in Figure 15, the mould form accuracy is transferred well, can successfully take out goods.

Figure 29 is the longitudinal section of the 3rd example of the finishing die that uses in the manufacture method of expression fuel cell separator 1 of the present invention, this finishing die 210 is identical with finishing die shown in Figure 3 10 in fact, same section adds 200 on Fig. 3 symbol, constitute new symbol, and each several part describes in detail and omits.

This finishing die 210 is with the difference of finishing die 10 shown in Figure 3: good release property after being shaped in order to ensure fuel cell separator 1, die cavity 250 sides of joining with demarcation strip 1, promptly, at the inner punch 222 and the cavity side surface of outer ram 225 down down, the cavity side surface of mould 230, last inner punch 242 and the cavity side surface of going up outer ram 245 impose diamond-like carbon (Diamond-Like Carbon, below brief note is " DLC ") handle, form the DLC film.

Figure 30 and Figure 31 are expressed as film method, as DLC film build method one example, use the ionization vapour deposition method, and the cavity side surface that reaches outer ram 245 at last inner punch 242 forms the DLC film.

Ionization vapour deposition method shown in Figure 30 is the PVD method, uses gasification benzene (C ₆H ₆) as the hydrocarbon gas of raw material, utilize by hot filament, anode, the direct-current discharge ion source that the reflector three-stage structure constitutes is as plasma source.

For this reason, this DLC film formation device 260 comprises filament 261 and filament supply 262, anode 263 and anode supply 264, and reflector 265 and reflector power supply 266 are as the last inner punch 242 (Figure 30) of object or the bias supply 268 of last outer ram 245 (Figure 31) usefulness.

Use this this DLC film formation device 260, decompose hydrocarbon gas with the arc discharge plasma in the high vacuum, electrically the ion in the accelerate plasma and the excitation molecule, by upwards cavity side surface (Figure 30) collision of inner punch 242, can form DLC film 242a on the cavity side surface of last inner punch 242.

Equally, can form DLC film 245a on the cavity side surface of last outer ram 245 (Figure 31).

Have again, same, can form DLC film 222a on the cavity side surface of following inner punch 222, at the cavity side surface formation DLC of following outer ram 225 film 225a, form DLC film 230a (with reference to Figure 29) on the cavity side surface of mould 230.

Above-mentioned DLC film 222a, 225a, 230a, 242a, 245a have fine and closely woven non crystalline structure, and the surface is very level and smooth, has abrasion performance, low-friction coefficient, feature such as release property is good.Thickness 1～1.5 μ m, hardness is HV3000～4000.

In the manufacturing of the fuel cell separator 1 that uses this finishing die 210 is handled, filling and compression section are identical with finishing die 10 occasions shown in Figure 3, adjust preceding (with reference to Fig. 6) by filling, in the time of will compressing after the filling adjustment (with reference to Fig. 7), in the middle of the compression section (with reference to Fig. 8), compression finishes back (with reference to Fig. 9) order and carries out.

Take out the goods operation after being shaped by (with reference to Figure 10) before taking out, extract stream slot part (with reference to Figure 11), extract mould (with reference to Figure 12), extract goods end (with reference to Figure 13) order and carry out.

In extracting stream slot part operation (with reference to Figure 11), from vpg connection, to compare with centering on portion 4, the release property of stream slot part 2 is poor, extracts the mould of stream slot part 2 from demarcation strip 1.That is, at last outer ram 245, under the state that the power effect that following outer ram 225 pushes towards demarcation strip 1, if the top pressure head rises, then going up inner punch 242 above outer rams 245 is supporting point, same, following inner punch 222 following outer rams 225 are supporting point, are acting on from the power of demarcation strip 1 demoulding.Total (the d of flow passage groove 3 ladders of top pressure head rising demarcation strip 1 both ends of the surface ₁+ d ₂) time, the flow passage groove 3 of demarcation strip 1 both ends of the surface breaks away from mould.

At this moment, owing to form the good DLC film 242a of release property on the cavity side surface of last inner punch 242, although shape is difficult to the demoulding,, the stream slot part 2 above the demarcation strip 1 and the demoulding of last inner punch 242 can be very smooth.

Equally, owing to form the good DLC film 222a of release property on the following cavity side surface of inner punch 222, although shape is difficult to the demoulding,, the stream slot part 2 below the demarcation strip 1 and the demoulding of following inner punch 222 can be very smooth.

In addition, in mould is chosen operation (with reference to Figure 12),, form DLC film 230a on the cavity side surface of mould 230 owing to make when mould 230 descends, therefore, although the contact-making surface effect of demarcation strip 1 side face and mould 230 has internal stress, the also demoulding smoothly.

According to this finishing die 210, graphite containing ratio height, by using the compression molding of the mobile dusty material that lacks, when making demarcation strip, can make and the gas flow path slot part zone on demarcation strip surface and around the density balance homogeneous in portion zone improve release property, the distortion of inhibition when mould takes out goods, warpage, fracture can obtain the high demarcation strip of high-quality and productivity.

And, in order to improve the goods release property, adopt the pattern draft that for example strengthens mould, or append the pin of choosing, or method occasion such as coating release agent, need the change article shape, cause that cost rises, and the present invention does not need to change article shape, can not cause that cost rises, and can realize good release property.

In above-mentioned example, the good release property after being shaped in order to ensure fuel cell separator 1 is all carried out DLC film 222a on the cavity side surface that the demarcation strip 1 of finishing die 210 joins, 225a, 230a, 242a, the film forming of 245a is handled, but the present invention is not limited thereto.

That is,, therefore, be preferably because the back that is shaped makes the demarcation strip 1 as goods remain in low punch (counterdie) 221 sides, at least be difficult in shape the demoulding on the cavity side surface of inner punch 242 form DLC film 242a.Again, be preferably, also form DLC film 245a on the cavity side surface of last outer ram 245.

Have again, be preferably, also form DLC film 222a on the cavity side surface of the following inner punch 222 that is difficult to the demoulding in shape.

No matter which kind of occasion, among the cavity side surface that joins for demarcation strip 1, do not carry out the part that DLC film film forming is handled with finishing die 210, be preferably, by suitable surface treatments such as for example TiC films, improve release property.

As such hard film, except DLC, can also use for example TiN, SiN, CrN, Cr ₂Nitride such as N, TiC, SiC, VC, B ₄Carbide such as C etc.It is good that the relative steel of described nitride and carbide connect airtight power, therefore, can form and such connect airtight power good film layer as the 1st layer, forms DLC thereon as the 2nd layer.

As becoming membrane means (film formation means), can use vacuum evaporation, (cathode) sputtering, ionization bundle evaporation, ion plating, known film such as chemical vapor deposition forms means.

Again, the film forming that such release property is good is handled and is not only applicable to finishing die shown in Figure 3 10, and can be equally applicable to finishing die shown in Figure 22 110.

As mentioned above, the present invention includes patrix and counterdie, described counterdie be divided into the internal mold corresponding with above-mentioned stream slot part and with around the corresponding external mold of portion, between described upper die and lower die, form die cavity, when described die cavity packet powder shape material, the described relatively external mold of described internal mold is positioned at institute take the altitude top, so that the compression ratio of described stream slot part and the described compression ratio that centers on portion become homogeneous, therefore, the compression ratio around portion zone and stream slot part zone of demarcation strip equalization can be set at, the demarcation strip of homogeneous density can be made.

Again, the present invention includes side's mould and the opposing party's mould, the single face subtend of described the opposing party's mould and side's mould, and be divided into the internal mold corresponding with above-mentioned stream slot part and with around the corresponding external mold of portion, after shortening shape into by described side's mould and the opposing party's mold pressing, during for the die sinking of taking-up formed products, make the described relatively internal mold of described external mold outstanding, so that described stream slot part than described around the demoulding of portion elder generation, therefore, in taking out demarcation strip, can before elastic recovery takes place, make the first demoulding in zone of described stream slot part, can make the damaged demarcation strip of amorphism.

Have, the present invention couple handles with the local at least good film forming of release property that imposes in mould surface that powder body material joins again, and therefore, release property is good, can suppress to deform, and warpage ruptures, and can make the high fuel cell separator of high-quality and productivity.

Finishing die of the present invention can be formed by metal, but is not limited to metal, also can be formed by other materials.

Above with reference to description of drawings embodiments of the invention, but the present invention is not limited to the foregoing description.Can do all changes in the technology of the present invention thought range, they all belong to protection scope of the present invention.

Claims (24)

1. the finishing die of a fuel cell separator uses the powder shaped material, and compression molding is provided with the fuel cell separator of the stream slot part and the portion of centering at least at single face, comprising:

Counterdie, with above-mentioned single face subtend, and be divided into the internal mold corresponding with above-mentioned stream slot part and with described around the corresponding external mold of portion;

Action component makes described internal mold and/or external mold advance and retreat.

2. the finishing die of fuel cell separator as claimed in claim 1 is handled the local at least good film forming of release property that imposes in described mould surface of joining with described powder body material.

3. the finishing die of a fuel cell separator uses the powder shaped material, and compression molding is provided with the fuel cell separator that the stream slot part reaches the portion of centering at each face of the table back of the body, comprising:

Patrix, be divided into the last internal mold corresponding with above-mentioned stream slot part and with described around the corresponding last external mold of portion;

Counterdie, be divided into the core insert corresponding with above-mentioned stream slot part and with described around the corresponding following external mold of portion;

A certain side moves with stamping press in patrix and the counterdie;

Framework forms the die cavity periphery between described patrix and the counterdie;

Action component makes the described described relatively internal mold of going up of external mold of going up advance and retreat;

Action component makes described core insert and described external mold down advance and retreat mutually.

4. the finishing die of fuel cell separator as claimed in claim 3 further is provided with the action component that makes that the described relatively upward external mold of described upward internal mold is advanced and retreat.

5. the finishing die of fuel cell separator as claimed in claim 3, make that the described action component of described core insert advance and retreat causes, make the outstanding action force of the described relatively external mold down of described core insert, be set at following size: when the compression section end that above-mentioned stamping press causes, outstanding the separating in fact of above-mentioned core insert disappears.

6. the finishing die of fuel cell separator as claimed in claim 4, make that the described described action component of going up the internal mold advance and retreat causes, make the described described relatively outstanding action force of external mold of going up of internal mold of going up, be set at following size: when the compression section end that above-mentioned stamping press causes, above-mentioned outstanding separating in fact of going up internal mold disappears.

7. as the finishing die of each described fuel cell separator among the claim 3-6, make that the described action component of going up the external mold advance and retreat causes, make the described described relatively outstanding stroke of internal mold of going up of external mold of going up, and make that the action component of described down external mold advance and retreat causes, make the outstanding stroke of the described described relatively core insert of external mold down, the degree of depth of described stream slot part that is set at and shows to carry on the back each face is in fact more than the same size.

8. as the finishing die of each described fuel cell separator among the claim 3-6, the cavity side surface of internal mold imposes the good film forming of release property and handles on described at least.

9. the finishing die of fuel cell separator as claimed in claim 8, the cavity side surface of external mold and/or described core insert imposes the good film forming of release property and handles on described.

10. the manufacture method of a fuel cell separator is used mould, with the compression molding of powder shaped material, makes the fuel cell separator that is provided with the stream slot part and the portion of centering at least at single face;

Counterdie be divided into the internal mold corresponding with above-mentioned stream slot part and with described around the corresponding external mold of portion, when being filled to the powder shaped material in the die cavity that is formed between patrix and the described counterdie, the described relatively external mold of described internal mold is positioned at institute take the altitude top, so that the compression ratio of described stream slot part and the described compression ratio that centers on portion become homogeneous.

11. the manufacture method of fuel cell separator as claimed in claim 10, during action is contracted in mold pressing, make described location the described relatively external mold of described internal mold difference in height decrescence, the mould release is simultaneously separated in fact and is disappeared.

12. the manufacture method of a fuel cell separator is used mould, with the compression molding of powder shaped material, makes the fuel cell separator that is provided with the stream slot part and the portion of centering at least at single face;

Mould comprises side's mould and the opposing party's mould, described the opposing party's mould and described single face subtend, and be divided into the internal mold corresponding with above-mentioned stream slot part and with around the corresponding external mold of portion, after shortening shape into by described side's mould and the opposing party's mold pressing, during for the die sinking of taking-up formed products, make the described relatively internal mold of described external mold outstanding, so as described stream slot part than described around the demoulding of elder generation of portion.

13. the manufacture method of a fuel cell separator is used mould, with the compression molding of powder shaped material, makes the fuel cell separator that is provided with the stream slot part and the portion of centering at least at single face;

Mould comprises side's mould and the opposing party's mould, described the opposing party's mould and described single face subtend, and be divided into the internal mold corresponding with above-mentioned stream slot part and with around the corresponding external mold of portion, by described side's mould, the opposing party's mould and the framework that is formed on the die cavity periphery between described two moulds are after the compression molding, during for the die sinking of taking-up formed products, make the described relatively internal mold of described external mold outstanding, so as described stream slot part than described around the demoulding of elder generation of portion;

The demoulding of described stream slot part and described centering under portion's not demoulding state, above-mentioned framework is moved, make the formed products periphery separate with this framework.

14. manufacture method as claim 12 or 13 described fuel cell separators, during described die sinking, make the described relatively internal mold of described external mold outstanding, so that described stream slot part is than described during around the demoulding of portion elder generation, spray compressed air from the divisional plane of described internal mold and outer metal film, so that the easy demoulding of described stream slot part.

15. the manufacture method of a fuel cell separator is used mould, with the compression molding of powder shaped material, is manufactured on the fuel cell separator that each face of the table back of the body is provided with the stream slot part and the portion of centering on;

Patrix be divided into the last internal mold corresponding with above-mentioned stream slot part and with described around the corresponding last external mold of portion, counterdie be divided into the core insert corresponding with above-mentioned stream slot part and with described around the corresponding following external mold of portion, when being filled to the powder shaped material in the die cavity that is formed between the described upper die and lower die, the described relatively external mold down of described core insert is positioned at institute take the altitude top, so that the compression ratio of described stream slot part and the described compression ratio that centers on portion become homogeneous;

During action is contracted in mold pressing, make the described relatively external mold down of the described core insert of described location difference in height decrescence, the mould release simultaneously, described difference in height is separated in fact and is disappeared.

16. the manufacture method of a fuel cell separator is used mould, with the compression molding of powder shaped material, is manufactured on the fuel cell separator that each face of the table back of the body is provided with the stream slot part and the portion of centering on;

Patrix be divided into the last internal mold corresponding with above-mentioned stream slot part and with described around the corresponding last external mold of portion, counterdie be divided into the core insert corresponding with above-mentioned stream slot part and with described around the corresponding following external mold of portion, when being filled to the powder shaped material in the die cavity that is formed between the described upper die and lower die, make outstanding being positioned at above institute's take the altitude of the described relatively external mold down of described core insert earlier, so that the compression ratio of described stream slot part and the described compression ratio that centers on portion become homogeneous;

Then, under described positioning states, above the powder shaped material in being filled to die cavity, described patrix makes the described described relatively external mold of going up of internal mold of going up be projected into quantitatively below of institute, when make described patrix drop to described go up external mold below the described powder shaped material of contact above height the time, along with the described internal mold of going up enters described powder shaped material, make described core insert descend, make the described relatively external mold down of described core insert be positioned at described and go up internal mold relative described to go up external mold equal toward the overhang of below toward the overhang of top.

17. the manufacture method of fuel cell separator as claimed in claim 16, during action is contracted in mold pressing, make the described described relatively overhang that goes up the past below of external mold of internal mold that goes up of described location, and the overhang of the described relatively past top of external mold down of described core insert decrescence, the mould release is simultaneously separated in fact and is disappeared.

18. the manufacture method of a fuel cell separator is used mould, with the compression molding of powder shaped material, is manufactured on the fuel cell separator that each face of the table back of the body is provided with the stream slot part and the portion of centering on;

Patrix be divided into the last internal mold corresponding with above-mentioned stream slot part and with described around the corresponding last external mold of portion, counterdie be divided into the core insert corresponding with above-mentioned stream slot part and with described around the corresponding following external mold of portion, after described patrix and counterdie compression molding, during for the die sinking of taking-up formed products, make and describedly go up that external mold and described external mold down are described relatively goes up internal mold and described core insert is outstanding, so as to make described stream slot part that described table carries on the back each face than described around the demoulding of elder generation of portion.

19. the manufacture method of fuel cell separator as claimed in claim 18, by described patrix, counterdie and the framework that is formed on the die cavity periphery between described two moulds, after the compression molding, during for the die sinking of taking-up formed products, make the described external mold and the described relatively upward internal mold of described external mold down and described core insert gone up give prominence to;

The demoulding of described stream slot part and the described of each face of the table back of the body at each face of the table back of the body move above-mentioned framework under portion's not demoulding state, make the formed products periphery separate with this framework.

20. manufacture method as claim 18 or 19 described fuel cell separators, during described die sinking, make when described upward external mold and the described relatively upward internal mold of described external mold down and described core insert are outstanding, from the described internal mold of going up, core insert and the described adventitia of going up, the divisional plane ejection compressed air of following external mold is so that the easy demoulding of described stream slot part of each face of the table back of the body.

21. a fuel cell separator is provided with the stream slot part and the portion of centering at single face at least, the density of material of described stream slot part and the described density of material that centers on portion form homogeneous in fact.

22. fuel cell separator, at least be provided with the stream slot part and the portion of centering at single face, counterdie be divided into the internal mold corresponding with above-mentioned stream slot part and with described around the corresponding external mold of portion, make the described relatively external mold of described internal mold be positioned at institute take the altitude top, form die cavity, the powder shaped material is filled in the described die cavity, along with compression section, disappear by making the difference in height of described external mold and internal mold separate, make that the compression ratio and the described compression ratio that centers on portion of described stream slot part are homogeneous, compression molding.

23. fuel cell separator, be provided with two sides stream slot part at each face of the table back of the body, the single face stream slot part and the portion of centering on, the density of material of described two sides stream slot part, the density of material of described single face stream slot part and the described density of material that centers on portion form homogeneous in fact.

24. a fuel cell separator is provided with two sides stream slot part at each face of the table back of the body, the single face stream slot part and the portion of centering on;

Counterdie be divided into described around the corresponding following external mold of portion and with described two sides stream slot part and the corresponding core insert of single face stream slot part, make the described relatively external mold down of described core insert be projected into quantitatively top of institute;

Patrix be divided into described around corresponding the last external mold of portion and with described two sides stream slot part and corresponding the last internal mold of single face stream slot part, make described go up internal mold described relatively go up external mold be projected into institute quantitative below;

The powder shaped material is filled in the die cavity that is formed by described counterdie and patrix,,, makes that the compression ratio of described stream slot part and the described compression ratio that centers on portion are homogeneous, compression molding by making outstanding the separating of described core insert and last internal mold disappear along with compression section.

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