JP4694347B2 - Manufacturing method of casting mold - Google Patents

Description

  The present invention relates to a method for producing a casting mold used for producing a casting by a vanishing model casting method, a method for producing a casting using the mold, and a model for the vanishing model casting method.

  The disappearance model casting method is also called a full mold method, and a model of a synthetic resin foam having a shape corresponding to a cast product is embedded in a heat-resistant aggregate such as foundry sand (hereinafter referred to as foundry sand). In this casting method, a molten metal (molten metal) is poured (poured) into the model portion to replace the model with the molten metal, thereby obtaining a cast product. Compared to the conventional casting method using a sampling model such as a wooden mold, the casting method is characterized in that a complicated casting product can be obtained because it is not necessary to consider the cutting mold. Synthetic resin foam is low in strength compared to molds, etc., so it is difficult to apply strong force when filling molding sand, etc., and the filling density of casting sand tends to be low, making the model complex The tendency becomes stronger at the site. As a result, seizure caused by the penetration of the molten metal between particles such as foundry sand tends to occur.

  To solve these problems, a coating agent composed of a heat-resistant aggregate or binder is applied to the surface of the synthetic resin foam model, and the molten metal is formed by a heat-resistant film (hereinafter referred to as a coating film) formed thereby. It is generally performed to prevent the penetration of the steel and prevent the seizure. However, since the coating agent is not directly applied to the casting sand or the like of the mold, the anchor effect obtained by the penetration of the coating agent into the mold cannot be expected, and it is difficult to increase the bonding force between the coating film and the mold. In addition, the bonding strength is more likely to decrease at a portion where the packing density such as foundry sand is reduced. For these reasons, the coating film is easily removed and peeled off by heat and pressure applied during pouring, and seizure is likely to occur at the site.

As measures for these improvements, metal fibers and the like were blended into the coating agent to reinforce the coating film (Patent Document 1 below), and a particle layer was formed on the surface of the coating agent to improve the bonding strength with the mold. (Patent Document 2 below), the inside of the synthetic resin foam model is hollowed, and the pressurized gas is sent from the outside into the hollow part to prevent the coating film from falling off by the internal pressure (Patent Document 3 below), etc. Is being considered.
JP 2000-15393 A JP 2000-117391 A JP 2000-140994 A

  An object of the present invention is to provide a method for obtaining a casting mold for a disappearing model casting method that can further reduce seizure defects, and in particular, filling a casting product corner or casting sand that is easily exposed to heat from a molten metal. It is an object of the present invention to provide a method for producing a mold for a disappearing model casting method that can obtain a good casting product with few seizure defects even in a difficult and difficult part.

  The inventors of the present invention used a conventional coating agent to produce a structure containing organic fibers, inorganic fibers, and a thermosetting resin when producing a casting mold that is molded using a heat-resistant aggregate and a disappearance model. Applying to the synthetic resin foam model on parts that are prone to seizure defects even when using, i.e., parts with complex shapes that are difficult to fill, such as cast product corners and casting sand that are easily exposed to heat from the molten metal. It has been found that a good casting product with few seizure defects can be obtained by substituting with a mold.

  The present invention has been made on the basis of the above knowledge, and is a method for producing a casting mold that is formed using a heat-resistant aggregate and a disappearance model, and includes organic fibers, inorganic fibers, and thermosetting resins. A casting production mold manufacturing method, wherein a structure to be contained is disposed so that at least a part thereof is in contact with the disappearance model, and further, heat-resistant aggregate is filled around the disappearance model in which the structure is disposed. I will provide a.

  Moreover, this invention provides the manufacturing method of a casting using the casting_mold | template for casting manufacture obtained by the manufacturing method of the said invention.

  Further, the present invention is configured to include a model main body made of a synthetic resin foam and a structure containing organic fibers, inorganic fibers, and a thermosetting resin, and at least a part of the model main body is in contact with the model main body. A model for the disappearance model casting method is provided in which the structure is disposed.

According to the present invention, the following effects are exhibited.
The structure used in the present invention is excellent in hot strength and shape retention even at the time of casting. Thus, seizure defects can be reduced, and man-hours for manufacturing such as suspension work can be reduced. In addition, since it is difficult for the molten metal to flow, defects due to foreign matter can be reduced.

Hereinafter, the present invention will be described based on preferred embodiments thereof.
The structure used in this embodiment contains organic fibers, inorganic fibers, and a thermosetting resin.

  The compounding ratio of the organic fiber, the inorganic fiber, and the thermosetting resin is the organic fiber / the inorganic fiber / the thermosetting resin = 1-50 / 1-40 / 2-50 (mass ratio). Is preferred.

  The structure preferably contains inorganic particles from the viewpoints of heat resistance and economy. In that case, the blend ratio of the organic fibers, the inorganic fibers, the inorganic particles, and the thermosetting resin is the organic fibers. / Inorganic fiber / Inorganic particle / Thermosetting resin = 1 to 50/1 to 40/10 to 95/2 to 50 (mass ratio), and further 2 to 40/2 to 30/20 to 90/4. It is preferable that it is -40 (mass ratio), especially 4-30 / 4-20 / 30-85 / 6-30 (mass ratio).

  The blending ratio of the organic fibers is preferably determined from the viewpoint of the moldability of the structure and the normal temperature strength at the lower limit, and the upper limit from the viewpoint of casting surface defects accompanying an increase in the amount of gas generated from the structure during casting. The

  In addition, the blending ratio of the inorganic fibers is preferably determined in terms of the lower limit from the viewpoint of shape retention during casting of the structure, and the upper limit from the viewpoint of moldability of the structure and structure removal after casting. Is done.

  Furthermore, the upper limit of the blending ratio of the inorganic particles is determined from the viewpoint of heat resistance during casting of the structure, and from the viewpoint of formability of the structure and shape retention during casting.

  Furthermore, the blending ratio of the thermosetting resin is such that the lower limit is the normal temperature strength of the structure and the shape retention or surface smoothness during casting, and the upper limit is the amount of gas generated from the structure during casting. From the viewpoint of casting surface defects accompanying the increase, a preferable range is determined.

  The organic fiber is a component that forms a skeleton in a state before being used for casting in the structure, contributes to maintaining strength at room temperature, and improves the moldability of the structure.

  Examples of the organic fibers include paper fibers, fibrillated synthetic fibers, and recycled fibers (for example, rayon fibers). These organic fibers can be used alone or in combination of two or more. Among these, it is particularly preferable to use paper fibers because they can be formed into various forms by papermaking and sufficient strength can be obtained after dehydration and drying.

  Examples of the paper fiber include wood pulp, cotton pulp, linter pulp, bamboo straw and other non-wood pulp. As the paper fiber, these virgin pulp or waste paper pulp can be used alone or in combination of two or more. The paper fiber is particularly preferably used paper pulp from the viewpoints of easy availability, environmental protection, and reduction of manufacturing costs.

  The organic fiber preferably has an average fiber length of 0.3 to 2.0 mm, particularly 0.5 to 1.5 mm in consideration of moldability of the structure, surface smoothness, and impact resistance.

  The inorganic fiber is a component that maintains its shape without being burned by the heat of the molten metal when used mainly for casting.

  Examples of the inorganic fibers include artificial mineral fibers such as carbon fibers and rock wool, ceramic fibers, and natural mineral fibers. These inorganic fibers can be used alone or in combination of two or more. Among these, it is preferable to use pitch-based or polyacrylonitrile (PAN) -based carbon fibers having high strength even at high temperatures from the viewpoint of effectively suppressing shrinkage associated with carbonization of the thermosetting resin, and in particular, PAN-based carbon. Fiber is preferred.

  The inorganic fiber has an average fiber length of 0.2 to 10 mm, particularly 0.5 to 8 mm from the viewpoint of dewaterability when paper is formed and dehydrated, moldability of the structure, and uniformity. Is preferred.

  The inorganic particles are components that are softened by the heat of the molten metal to form a dense refractory film and improve the heat resistance of the structure.

  Examples of the inorganic particles include inorganic particles having a fire resistance of 800 to 2000 ° C., preferably 1000 to 1700 ° C. such as silica, alumina, mullite, magnesia, zirconia, mica, graphite, obsidian, and the like. From the viewpoint of forming a dense refractory film, obsidian and mullite powder are preferable. These inorganic particles may be used alone or in combination of two or more. The inorganic particles preferably have a particle diameter of 200 μm or less. In particular, inorganic particles having a fire resistance of ± 300 ° C., particularly ± 200 ° C. with respect to the casting temperature of the molten metal to be cast are preferable. Here, the fire resistance of the inorganic particles is measured by a measuring method (JIS R2204) using a Zeger cone.

Examples of the thermosetting resin include thermosetting resins such as phenol resins, epoxy resins, and furan resins. The thermosetting resin is a component that improves the strength of the structure at room temperature and the strength during hot, that is, shape retention during casting. Moreover, it is thermally decomposed by the heat at the time of casting, and the resulting carbon film imparts smoothness to the surface of the structure, resulting in the effect of improving the surface smoothness (casting surface) of the casting.
The thermosetting resin has particularly low generation of combustible gas, has a combustion suppressing effect, has a high residual carbon ratio of 25% or more after pyrolysis (carbonization), and is good for forming a carbon film during casting. It is preferable to use a phenol-based resin from the viewpoint that a smooth casting surface can be obtained. The residual carbon ratio can be determined from the residual mass after heating to 1000 ° C. in a reducing atmosphere (under a nitrogen atmosphere) by an analytical thermal analysis.

  Examples of the phenolic resin include novolak phenol resins, resol type phenol resins, modified phenol resins modified with urea, melamine, epoxy, and the like, preferably novolak phenol resins or modified resins thereof.

  The thermosetting resins may be used alone or in combination of two or more, and may be used in combination with an acrylic resin, a polyvinyl alcohol resin, or the like.

  As the addition form of the thermosetting resin, the organic fiber, the inorganic fiber or the inorganic particles are coated, powdered or emulsified and added to the raw material slurry, and after the paper making and dry-molded, Improves the strength of the structure by impregnating the organic fiber, the inorganic fiber and the inorganic particle, making the molded body after making, drying or curing, and maintaining the strength by carbonizing with the heat of the molten metal at the time of casting And what to do. In any case, a carbon film is formed by carbonization by the heat applied from the molten metal at the time of casting, and it is added if it can contribute to maintaining the strength of the structure and the like and improving the surface smoothness of the casting. May be either.

  Since the curing agent required when the novolak phenol resin is used is easily dissolved in water, it is preferably applied after dehydration of the molded body, particularly in the case of wet papermaking. It is preferable to use hexamethylenetetramine or the like as the curing agent.

  In the structure of the present embodiment, in addition to the organic fiber, the inorganic fiber, the inorganic particle, and the thermosetting resin, paper such as polyvinyl alcohol, carboxymethyl cellulose (CMC), and polyamidoamine epichlorohydrin resin is used as necessary. Other components such as a force-strengthening material, a polyacrylamide-based flocculant, and a colorant can be added at an appropriate ratio.

  The thickness of the structure according to the present embodiment can be appropriately set according to the portion used, but the thickness at least in the portion in contact with the molten metal is 0.2 to 5 mm, particularly 0.4 to 2 mm. Is preferred. If it is too thin, the strength required to mold the mold by filling with heat-resistant aggregate will be insufficient, and if it is too thick, the amount of gas generated will increase during casting and surface defects of the casting will easily occur, and the molding time will be increased. May become longer and manufacturing costs may be higher. However, the thickness of the structure means a portion excluding a structure (unevenness, protrusion, etc.) for providing a bond strength with a reinforcing rib or heat-resistant aggregate exclusively for giving mechanical strength to the structure. Point to.

  The structure of this embodiment has a stronger bond with the heat-resistant aggregate by providing a structure and / or an adhesive layer for bonding to the heat-resistant aggregate on the surface of the structure that contacts the heat-resistant aggregate. Thus, the dimensional accuracy of the mold can be further improved. Examples of the structure for bonding with the heat-resistant aggregate include a concave portion, a convex portion, a protrusion, and a combination thereof. When providing a protrusion, the protrusion height is preferably 5 to 20 mm with respect to the adjacent portion. If it is too low, the bonding effect is reduced, and if it is too high, the mold strength is reduced due to edge breakage.

  For the adhesive layer, acrylate-based, vinyl butyral-based, vinyl alcohol-based, vinyl acetate-based, phenol-based adhesives, etc., alone or as a mixture of two or more water-based emulsions, diluted with water or alcohol-based organic solvents Can be formed by applying to the surface of the structure in contact with the heat-resistant aggregate, or by applying a double-sided tape-like material made of these adhesives. Among these, from the viewpoint of the working environment, it is preferable to apply a water-based emulsion or water-solubilized one or a double-sided tape-like one. The adhesive is a substance used for bonding two objects together, but includes an adhesive that can be used for temporary adhesion and can be peeled off later.

  When the structure of the present embodiment is manufactured through a paper making process using a raw material slurry using water as a dispersion medium, from the point of suppressing the amount of gas generation during casting as much as possible, in a state before being used for casting, The moisture content (mass moisture content) is preferably 10% or less, particularly preferably 8% or less.

  The structure of the present embodiment preferably has a specific gravity of 1.0 or less and 0.8 or less in the state before being used for modeling from the viewpoint of ease of modeling work due to lightness. Is more preferable.

  Next, the manufacturing method of the structure of the present invention will be described based on the manufacturing method of the mold or the like of the above-described embodiment as a preferred embodiment thereof.

  As an example of the structure manufacturing method of the present embodiment, a molding method using a wet papermaking method can be given. In the wet papermaking method, a raw material slurry containing the organic fiber, the inorganic fiber, the inorganic particles, and the thermosetting resin in the predetermined mixing ratio is prepared, and a fiber having a predetermined shape is obtained by a wet papermaking method using the raw material slurry. The laminated body is made, dehydrated and dried to produce a structure.

  Examples of the dispersion medium of the raw material slurry include water, white water, and solvents such as ethanol and methanol. Among these, from the viewpoints of papermaking / dehydration stability, quality stability, cost, ease of handling, etc. Water is particularly preferable.

  The total ratio of the fibers and inorganic particles to the dispersion medium in the raw slurry is preferably 0.1 to 10% by mass, particularly 0.5 to 6% by mass. If the total proportion of the fibers and particles in the raw slurry is too large, uneven thickness tends to occur. Conversely, if the amount is too small, a local thin portion may occur.

  If necessary, additives such as the paper strength reinforcing material, the flocculant, and the preservative can be added to the raw material slurry at an appropriate ratio.

  In the papermaking process of the fiber laminate, for example, a papermaking mold having a shape substantially corresponding to the shape of the structure is provided with a large number of communication holes communicating with the back of the mold and has a mesh on the papermaking surface of the mold. Cover with a net. In the paper making, the raw material slurry may be poured and deposited with the paper making surface facing up, or the paper making mold may be immersed in the raw material slurry and sucked and deposited from the back of the paper making mold.

  When a fiber laminate having a predetermined thickness is formed on the papermaking net, the fiber laminate is dehydrated to a predetermined moisture content by passing air through the fiber laminate as necessary.

  Next, the fiber laminate is dry-molded. In this dry molding step, any method may be used as long as the desired structure shape can be obtained. For example, the fiber laminate is sandwiched between a pair of heated and dry molds manufactured according to the target structure shape, and dry molding is performed. The drying temperature (mold temperature) of the drying mold is preferably 180 to 250 ° C., particularly preferably 200 to 240 ° C., from the viewpoint of drying time at the lower limit and surface property deterioration due to scorching.

  Further, if the desired structure shape is obtained in the state of the fiber laminate, it may be dried as it is with a hot air dryer or the like. In this case, the lower limit of the atmospheric temperature is preferably 160 to 240 ° C., particularly preferably 180 to 220 ° C., from the viewpoint of drying time as the lower limit and thermal decomposition of the organic fiber.

  If necessary, the obtained structure can be impregnated partially or entirely with a binder, and heated and thermally cured. Examples of the binder include colloidal silica, ethyl silicate, and water glass.

  Moreover, it is preferable to heat-treat the structure to promote curing of the thermosetting resin. By performing such heat treatment, a structure having more excellent shape retention can be obtained. Such heat treatment may be performed in combination with the drying molding step or may be performed separately using a hot air dryer or the like. The degree of cure of the thermosetting resin obtained by such heat treatment is preferably 30% or more, particularly 80% or more in terms of the amount of acetone insoluble in the following thermosetting resin.

Specifically, the insoluble content of the thermosetting resin is determined as follows.
That is, about 5 g of a sample is taken from the structure, pulverized with a mill, and the mass (a) is precisely weighed. The ground sample is added to a container together with acetone and shaken sufficiently, and then left at room temperature. Next, the pulverized sample is sufficiently filtered with a filter paper (mass (c)) so that the pulverized sample does not remain in the container, and the filtered pulverized sample is dried together with the filter paper to obtain them (crushed sample and filter paper). ) (B) is precisely weighed. And based on each obtained mass (a)-(c) and the theoretical mass (d) of components other than the said thermosetting resin in the said grinding | pulverization sample, the insoluble content amount of the said thermosetting resin (( %).
Insoluble content% = 100− (a− (b−d)) × 100 / (ad)

  In the above description, the method of dry-molding into the shape of the target structure at the time of wet papermaking was explained. However, the fiber laminate is made into a sheet at the time of wet papermaking, and the object is a wet sheet-like fiber laminate. Dry molding may be performed by sandwiching between a pair of heated and dry molds manufactured according to the shape of the structure. Still further, the fiber laminate that has been made into a sheet is dried in the form of a sheet, and the dried fiber laminate is appropriately cut, bent, and bonded to obtain the desired shape of the structure. You may get. For the bonding, an adhesive, a pressure-sensitive adhesive tape, a metal fitting such as a pin / claw can be used, and a method using an adhesive is preferable, and an adhesive made of a thermosetting resin is more preferable.

  Next, the manufacturing method of the casting casting mold of the present invention will be described based on its preferred embodiment.

  In the method for producing a casting mold according to this embodiment, the predetermined structure (for example, FIG. 1) obtained as described above is placed at a position where the synthetic resin foam model is easily baked (for example, as shown in FIG. 2). (FIG. 3), a coating agent is applied to the surface of the synthetic resin foam model other than the portion where the structure is disposed, and the coating agent is appropriately dried as necessary. Then, a casting mold can be manufactured by filling and molding the heat-resistant aggregate around the vanishing model in which the structure placed in the mold is disposed.

  For example, the position where the casting is easy to occur is a portion where the casting is thick and the solidification of the molten metal is slow, a casting bottom where a high molten metal pressure is applied during casting, or a molten metal where the mold protrudes toward the casting. This refers to areas that are likely to become severe due to heat or pressure, such as areas that are susceptible to high temperatures due to heat. Further, it can be said that the corner portion, pocket portion, overhang portion, etc. of the disappearing model, which is difficult to fill with casting sand or the like at the time of mold making, are easily baked.

  The said coating agent can use the normal thing used by the disappearance model casting method without a restriction | limiting in particular. From the viewpoint of exerting the performance of the structure, the coating agent is preferably not applied to the contact surface between the structure and the synthetic resin foam.

  Thereby, in this invention, the model for disappearance model casting methods comprised including the model main body which consists of a synthetic resin foam, and the structure which concerns on the said this invention is provided. The model body is formed from a synthetic resin foam such as expanded polystyrene, which is usually used in this field. It is preferable that at least a part of the structure is disposed in contact with the cast product forming portion of the model body. From the viewpoint of better manifesting the effects of the present invention, it is more preferable that the structure is disposed at a position where the above-described casting is easily seized with respect to the disappearance model.

  As the heat-resistant aggregate, normal ones conventionally used for producing this type of casting, including foundry sand, can be used without any particular limitation. If it is necessary to cure the heat-resistant aggregate with a binder, a normal one can be used without any particular limitation.

  Further, a casting production method using the casting production mold produced according to the present invention will be described based on its preferred embodiment.

  For example, a mold assembled as shown in FIG. 4 is poured by pouring molten metal from a pouring spout. At this time, the inorganic particles are softened by the heat of the molten metal to form a dense refractory film, and further, the cast skin improvement effect by the carbon film generated by the thermal decomposition of the thermosetting resin, Due to the hot shape retention effect and the like, the cast product portion in which the structure is arranged has extremely few seizure defects, and a sound casting with few defects as a whole can be manufactured.

  The present invention is not limited to the above-described embodiment, and can be changed as appropriate without departing from the spirit of the present invention.

〔Example〕
<Preparation of raw material slurry>
After preparing a slurry of about 1% by mass in which the following organic fibers, inorganic fibers and inorganic particles were dispersed in water, the following thermosetting resin powder and an appropriate amount of the following flocculant were added to the slurry to prepare a raw material slurry. . In addition, it prepared in the ratio of organic fiber / inorganic fiber / inorganic particle / thermosetting resin powder = 25/10/45/20 (parts by mass).
Organic fiber: used newspaper (average fiber length 1mm, freeness (CSF, the same applies below) 150cc)
Inorganic fiber: PAN-based carbon fiber (“Toray Chop” manufactured by Toray Industries, Inc., fiber length 3 mm, shrinkage 0.1%)
Inorganic particles: Obsidian (“Nice catch” manufactured by Kinsei Matec Co., Ltd., average particle size 30 μm)
Thermosetting resin: Novolac phenolic resin ("SP1006LS" manufactured by Asahi Organic Materials Co., Ltd., residual charcoal rate 38%)
Flocculant: Polyacrylamide flocculant (“A110” manufactured by Mitsui Cytec)

<Paper forming molding of structure>
For the papermaking mold, a mold having a papermaking surface corresponding to the structure shown in FIG. 1 is used, a net having a predetermined mesh is arranged on the papermaking surface, and a large number of communication holes communicating the papermaking surface and the back surface are provided. The formed one was used. Furthermore, the papermaking mold was set with a frame for slurry introduction with the papermaking surface facing up. Then, the raw material slurry was circulated by a Mono pump, and while a predetermined amount of slurry was put into the frame on the papermaking mold, it was drained through the communication hole, and a predetermined fiber laminate was deposited on the surface of the net. . After completing the introduction of a predetermined amount of raw material slurry, a negative pressure of 0.05 MPa was applied from the back of the papermaking mold on which the fiber laminate was deposited, and air was vented for about 30 seconds to dehydrate the fiber laminate. A liquid in which a 15% (mass ratio) curing agent (hexamethylenetetramine) of the thermosetting resin was dispersed in water was uniformly applied to the entire surface of the obtained fiber laminate. The fiber laminate was then removed from the papermaking mold and transferred to a dry mold heated to 220 ° C. As the dry mold, there was used a set of inside and outside corresponding to the structure shown in FIG. 1, in which a large number of communication holes communicating the molding surface and the outside were formed. In the dry molding step, the fiber laminate was sandwiched between a pair of inner and outer dry molds, and the fiber laminate was dried while transferring the shape of the target structure. After performing pressure drying for a predetermined time (180 seconds), the obtained molded body was taken out of the drying mold and cooled to obtain a structure having a thickness of 1.2 mm in the form shown in FIG.

<Manufacture of mold>
The structure shown in FIG. 1 is placed on the bottom of the pocket portion of the model molded into the shape shown in FIG. 2 using foamed polystyrene (50 times the expansion ratio) (FIG. 3), and a coating agent having the following composition is applied to the model surface. A dry film thickness of about 1 mm was applied. However, it implemented so that it might not adhere to the model body surface which the said structure and the said structure contact | connect. Thereafter, as shown in FIG. 4, a heat-resistant aggregate (flattery sand + furan resin / curing agent) was filled to form a mold.
* Coating agent composition, silica 28.9 (mass%)
・ Graphite 13.0 (mass%)
-Surfactant 2.0 (mass%)
・ Bentonite 3.0 (mass%)
・ Methylcellulose 6.0 (mass%)
・ Water residue (total 100% by mass)

<Manufacture of castings>
A molten metal (molten metal) having a casting material FC-300 and a casting temperature of 1380 ° C. was poured into the mold of FIG. 4 and solidified. Then, the mold was broken and the casting was taken out.

<Result (increased state)>
A casting having the same shape as the expanded polystyrene model shown in FIG. 5 was obtained. As for the casting surface, a casting having no seizure including the pocket portion was obtained.

[Comparative Example]
Except that the structure is not used, it is the same as the embodiment (FIG. 6).
<Results (state of occurrence of seizure)>
A casting having the same shape as the expanded polystyrene model shown in FIG. 7 was obtained. However, heavy seizure occurred at the bottom corner of the pocket, and mild seizure was seen at the bottom of the other pockets. No seizure was observed on the other casting surfaces. Severe baking refers to an item that cannot be removed by shot blasting but requires a “hanger” operation by a chipper or the like, and mild baking refers to an item that can be removed only by shot blasting.

It is a figure which shows typically one Embodiment of the structure used for the manufacturing method of the casting_mold | template of this invention. It is a figure which shows typically one Embodiment of the vanishing model before the structure of FIG. 1 is arrange | positioned. It is a figure which shows typically one Embodiment of the vanishing model in which the structure of FIG. 1 is arrange | positioned. It is the schematic which shows the casting method by the casting_mold | template shape | molded using the model of FIG. It is the schematic which shows the casting obtained by the casting method of FIG. It is the schematic which shows the casting method using the conventional vanishing model. It is the schematic which shows the casting obtained by the casting method of FIG.

Claims (5)

A method for producing a casting casting mold formed using a heat-resistant aggregate and a disappearance model, comprising organic fiber, inorganic fiber , thermosetting resin, and inorganic particles , on a surface in contact with the heat-resistant aggregate The structure having a structure for bonding with the heat-resistant aggregate is disposed so that at least a part thereof is in contact with the disappearance model, and the surface of the synthetic resin foam model other than the portion where the structure is disposed is disposed. A method for producing a casting mold, wherein a casting agent is applied, and further, heat-resistant aggregate is filled around the disappearance model in which the structure is arranged. The method for producing a casting mold according to claim 1 , wherein the structure for bonding to the heat-resistant aggregate is a protrusion having a height of 5 to 20 mm . It said structure is, the surface in contact with heat resistant aggregate, having a contact adhesive layer for binding the refractory aggregate, according to claim 1 or 2 method of manufacturing for casting molds according.   The said structure is obtained by the manufacturing method which comprises the papermaking process using the raw material slurry which contains the said organic fiber, the said inorganic fiber, and the said thermosetting resin at least in any one of Claims 1-3. The manufacturing method of the casting mold for description.   A casting production method using the casting production mold obtained by the production method according to claim 1.

Images