WO2005080023A1

WO2005080023A1 - Process for producing cast item

Info

Publication number: WO2005080023A1
Application number: PCT/JP2005/002893
Authority: WO
Inventors: Yusuke Kato; Toshihiko Zenpo; Norihiro Asano; Masahiko Nagasaka; Kazuyuki Nishikawa
Original assignee: Sintokogio, Ltd.
Priority date: 2004-02-25
Filing date: 2005-02-23
Publication date: 2005-09-01
Also published as: EP1721689B1; TW200533436A; CN1921969B; CN1921969A; EP1721689A1; JP3948490B2; US20070137825A1; EP1721689A4; ATE509714T1; JPWO2005080023A1

Abstract

A process for producing a cast item with the use of a mold capable of easily crumbling. There is provided a process comprising the step of mixing together a granular aggregate, at least one type of water-soluble binder and water to thereby obtain an aggregate mixture and agitating the aggregate mixture to thereby effect foaming. This aggregate mixture is capable of suppressing undesirable gas generation at the time of mold formation or melt casting. Further, there is provided a process comprising the step of filling a space for mold formation with the foamed aggregate mixture and evaporating water from the charged aggregate mixture to thereby solidify the aggregate mixture, thus accomplishing mold formation; the step of assembling the mold with another mold into a final mold; the step of casting a melt in the final mold; the step of, during the period of cooling of cast item after melt solidification, removing the mold from the cast item; and the step of performing heat treatment of the cast item.

Description

Specification

Food production method

Technical field

[0001] The present invention relates to a method for producing a product, and more particularly to a method for producing a product using a mold that can be easily removed instead of a conventional shell molding process.

Background art

[0002] As a conventional method for producing a light alloy preform, for example, as described in JP-A-5-261478, a shell mold process is known. As the binder for the shell mold process, a binder containing a phenol-formaldehyde resin is used. The sand coated with the binder is blown into a heated molding die, and the binder coated on the filled sand is cured by the heat of the die.

[0003] However, in such a shell mold process, since the core mold after pouring is relatively hard, it is necessary to disintegrate the core mold and remove it from the animal. This requires a knockout step of applying a large impact force to the core type. In order to perform this knock-out process, it is necessary to sufficiently cool the animal before heat-treating the animal. In addition, even if a relatively large impact force of IMpa or more is applied at 10 Hz or more for 10 sec or more, only 70-80% of the sand can be washed off. Some core sand and core lump will remain on the animal. Therefore, they may need to be removed again. Further, in order to regenerate the core mass removed from the fish, roasting is often required.

[0004] Further, in the shell mold process, when the binder is cured by the heat of the mold, generation of volatile gas is accompanied. Such volatile gases have an unpleasant odor, and gases such as formanolaldehyde, phenol, and ammonia have an adverse effect on the human body.

[0005] Therefore, instead of the conventional shell mold process, there is a demand for a method for producing a varnish that can easily remove the mold and suppress generation of volatile gas.

[0006] In the present specification, the term "particulate aggregate" refers to one or more of silica sand, zircon, sand, olivine sand, chromite sand, alumina sand, mullite sand, artificial sand, and the like. Consisting of To taste.

[0007] In the present specification, "after the molten metal is solidified" means after the molten metal has been solidified and hardened. This temperature differs depending on the process and the material of the molten metal.

[0008] In the present specification, "during the cooling period of the object" is a period during which the object is cooled below the temperature at which the object is cooled to such an extent that the object is not deformed even when the object is removed from the finished mold. Is shown. For example, in T6 treatment of aluminum alloys, the object is cooled to a temperature lower than the solution heat treatment temperature of about 520 ° C but higher than the normal cooling temperature of 70 to 111 ° C, for example, 300 ° C. Indicates the rejected period.

[0009] According to one aspect of the present invention, there is provided a method for producing a animal, the method comprising:

Forming an aggregate mixture by mixing at least one kind of particulate aggregate, at least one kind of water-soluble binder, and water, stirring the aggregate mixture and foaming; and a step of foaming the aggregate mixture. Is filled in a mold forming space, the water in the filled aggregate mixture is evaporated to solidify the aggregate mixture, and a mold is formed by the particulate aggregate, and

A step of manufacturing a completed mold by combining the mold of the other party with the mold formed by the particulate aggregate;

Pouring the molten metal into the finished mold,

Removing the molding mold from the molten metal during the cooling period of the solidified solid;

Heat treating the solid.

[0010] The mold III formed by the particulate aggregate is preferably a core III mold. In this case, the other type II (main type II) may be a mold or a sand type.

[0011] In the present specification, the "completed mold" includes a combination of a main mold and at least one molded mold (core mold) molded with particulate aggregate. Means hot water type 铸. Accordingly, the components of the finished mold can include elements necessary for pouring in addition to the main mold and the core mold. [0012] The method of the present invention for producing a product may further include a step of recovering the particulate aggregate and a step of regenerating the collected particulate aggregate. It is preferable that the collected and regenerated particulate aggregate is reused in the molding of a rectangular shape.

[0013] According to one embodiment of the present invention, the step of collecting and regenerating the particulate aggregate is mechanical regeneration.

[0014] The metal may be an aluminum alloy material, a magnesium alloy material, a copper alloy material, or the like.

[0015] The heat treatment may be T6 treatment or T7 treatment.

According to one embodiment of the present invention, the step of removing the mold る is a step of adding vibration to the mold 錡. This includes, for example, applying an impact force equal to or less than IMpa to Type III for less than 30 seconds at less than 30 Hz within 5 to 20 minutes after pouring.

[0017] A method for producing a substance provided by another aspect of the present invention includes a step of forming an aggregate mixture by mixing a particulate aggregate, at least one water-soluble binder, and water;

The aggregate mixture is agitated and foamed, and the foamed aggregate mixture is filled into a molding space for type III, and the moisture in the filled aggregate mixture is evaporated to solidify the aggregate mixture. A process of molding

A step of combining a core mold and a mold mold into a finished mold,

Pouring the molten aluminum alloy into the finished mold,

The method includes a step of removing the core mold from the solid during the cooling of the solid after the molten metal is solidified, and a step of performing a T6 or T7 heat treatment on the aluminum alloy.

[0018] The at least one water-soluble binder is at least one of polybutyl alcohol and a derivative thereof, or at least one of starch and a derivative thereof.

BEST MODE FOR CARRYING OUT THE INVENTION

FIG. 1 is a flow chart schematically showing each step of the method for producing a product according to the present invention.

First, the principle of the method for producing a product of the present invention will be described with reference to the process chart.

[0020] In FIG. 1, first, at least one kind of particulate aggregate, at least one kind of water-soluble binder and water are mixed to form an aggregate mixture, and the mixture is stirred to form a foam. (First (preparation) step 1).

[0021] Secondly, the aggregate mixture foamed in the previous step is filled in a space for mold making and solidified.

Then, a mold having a granular aggregate strength is formed (second (molding) step) 2).

Third, at least one or more molded molds (core molds) are combined with a counterpart mold (main mold) to produce a completed mold (third (assembly) process) 3).

Fourth, a molten metal is poured into the completed mold No. 4 (fourth (pour) step 4).

Fifth, during the cooling period of the solid after the molten metal has solidified, the core mold is removed from the solid and removed from the solid (fifth (mold removing) step 5).

Sixth, the finished product is manufactured by subjecting the product to a heat treatment (sixth (heat treatment) step 6).

Each step of FIG. 1 will be described in more detail.

[0027] In the first (preparation) step 1, the particulate aggregate is at least one of silica sand, zircon, sand, olivine sand, chromite sand, alumina sand, mullite sand, artificial sand, and the like. Use above

As the water-soluble binder, it is preferable to use a binder having water solubility at room temperature. A water-soluble binder having water solubility at room temperature can form an aggregate mixture without heating, so that the time and energy required for heating the binder and the particulate aggregate can be saved. This is an advantage of the present invention as opposed to coated sand production in a conventional shell mold process. The water-soluble binder used in the present invention is preferably one or both of polyvinyl alcohol or a derivative thereof, which is a water-soluble binder, and starch or a derivative thereof, but is not limited thereto. Since the water-soluble binder can be easily volatilized or decomposed, the core-type can be easily removed from the solidified solid of the molten metal in the fifth (removal) step 5 described later. The water-soluble binder is preferably contained in an amount of 0.1 to 5.0 parts by weight based on the particulate aggregate.

[0029] Such at least one water-soluble binder, at least one type of particulate aggregate, and water are mixed to form an aggregate mixture. When this is foamed by stirring, the aggregate mixture becomes whipped cream-like.

[0030] In the second (molding) step 2, the moisture in the aggregate mixture filled in the mold-forming space is removed. When the aggregate is solidified by evaporation, a hollow core type (core type) made of particulate aggregate is formed due to foaming in the previous step. This hollow mold has a porosity of 3% to 60%. When the thickness of the hollow mold is, for example, about 40 mm, the water-soluble binder is agglomerated by 50% or more in the mold surface layer between the mold surface and the depth of 10 mm. That is, in the hollow mold made of the foamed aggregate mixture, the air bubbles dispersed in the aggregate mixture and the water contained in the binder are gathered in the center of the mold, and the water is evaporated to obtain the water. At the center of the mold, the packing density of the aggregate is low.

[0031] In the third (assembly) step 3, a finished mold can be formed by combining at least one core mold made of particulate aggregate with a main mold (a mating mold). The main mold 錡 may be a mold or a sand mold made of, for example, particulate aggregate. In the present embodiment, a mold is adopted as the main mold and a low-pressure mold is applied. However, when a mold and a mold are adopted, the method of the present invention is not limited to low-pressure molding, and can be applied to other processes such as reverse pressure molding, die casting, and gravity mold molding.

In the fourth (pouring) step 4, the material of the molten metal to be poured into the completed mold is, in the present embodiment, a force which is an anoremium alloy. Other light metal alloys other than those described above Alternatively, it may be a non-ferrous alloy (for example, a magnesium alloy or a copper alloy). Alternatively, iron, steel, or an iron-based metal alloy may be used. However, when an iron-based metal is used, it would be desirable to apply a coating material to the core type.

[0033] In the fifth (unmolding) step 5, during the cooling period (a period in which the object is cooled to a temperature lower than the temperature at which the object was cooled so that the object was not deformed even when the object was removed from the completed mold). ) Remove the core type from the animal. Here, `` during the cooling period '' when the material of the molten metal in the fourth (pour) step 4 is an aluminum alloy is lower than the solution treatment temperature of about 520 ° C in the T6 treatment of the aluminum alloy, This is a period during which the animal is cooled to a temperature higher than the normal cooling temperature of 70 to 111 ° C, for example, 300 ° C.

[0034] In the case of an aluminum alloy, the heat treatment in the sixth (heat treatment) step 6 is a T6 treatment, a T7 treatment, or another heat treatment.

[0035] By using polybutyl alcohol or a derivative thereof or starch or a derivative thereof as the water-soluble binder, a particulate aggregate mixture containing the binder is kneaded. No unpleasant gas odor was generated in the preparation step 1 for adjustment and the molding step 2 for molding the core III mold.

[0036] In addition, in the pouring step 4 in which the molten metal is poured into the molded core 铸, even if the binder is heated by the heat of the molten metal, unpleasant odor from the core 铸 undesired. No volatile gas was generated.

As shown in FIG. 1, following the sixth (heat treatment) step 6, the following steps may be further added to the method for producing a product of the present invention, if necessary. That is, a recovery process 7 for recovering core 铸 type particulate aggregate (core sand) and a core lump, a crushing process 8 for crushing a core lump, and mechanically regenerating the collected particulate aggregate This is the mechanical regeneration process 9 to be performed. The recovered and regenerated particulate aggregate can be reused for core III molding.

[0038] A specific embodiment of the method for producing a product of the present invention will be described with reference to the process chart of Fig. 1. However, the material names shown here are for illustrative purposes, and do not limit the present invention.

[0039] In the first step (preparation step) 1 of the present embodiment, two types of aggregate mixtures A and B were obtained as follows.

[0040] Table 1 Aggregate mixture A

Particulate aggregate: Silica sand (Flaty sand) 100 parts by weight

Water-soluble binder: Polyvier alcohol IP— 05 Nippon vinegar (Poval) 0.8 parts by weight

Crosslinking agent: Butanetetracarboxylic acid (Likacid II-W, manufactured by Shin Nihon Rika) 0.2 parts by weight 100 parts by weight of an aggregate mixture having the composition shown in Table 1 and 6 parts by weight of water are mixed, stirred, kneaded and foamed. Then, a whipped cream-like aggregate mixture Α was obtained.

Table 2 Aggregate mixture B

Particulate aggregate: Silica sand (Flaty sand) 100 parts by weight

Water-soluble binder: Polybutyl alcohol FL-05 Nippon Vinegar Bi ', manufactured by Poval 0.2 parts by weight, starch (Dextrin ND-S, manufactured by Nichisei Danigaku) 1.0 part by weight, and cunic acid (manufactured by Fuso Chemical) ) 0.4 parts by weight

Mix 100 parts by weight of the dried aggregate mixture having the composition shown in Table 2 with 6 parts by weight of water, The mixture was stirred, kneaded and foamed to obtain a whipped cream-like aggregate mixture B.

[0042] In the preparation step 1 of the present embodiment, a heating device required in the step of manufacturing a resin-coated sand in the conventional shell mold process and a deodorizing device for removing harmful gas generated by heating the resin are required. ,.

Next, the two types of whipped cream-like aggregates obtained in the preparation step 1 were placed in a cavity (not shown) of a mold (not shown) for molding at a temperature of 250 ° C. Mixtures A and B were separately pressure-filled and held for 1 minute to evaporate and solidify the water in the aggregate mixture, and then the core 錡 was removed from the cavity of the 铸 molding die ( Second (molding) step 2).

As described above, this mold is assembled with another mold to make a completed mold (third (assembly) step 3). Here, in the assembling step 3 of the present embodiment, the core mold was incorporated into the main mold of the low-pressure molding apparatus, and a finished mold was manufactured to prepare for pouring.

The molten metal was poured into the completed mold No. 4 (fourth (pouring) step 4). In the present embodiment, a molten aluminum alloy material AC4C (at a temperature of 720 ° C.) was poured from below using a low-pressure forming apparatus (not shown). The temperature of 720 ° C of the molten metal volatilizes or decomposes the binder, so that the removal of the core mold in the next step becomes easy.

[0046] During the cooling period of the solid after the solidification of the molten metal, the core was removed from the solid (No. 5).

(Unmolding) process 5). In the conventional shell mode process, in order to disintegrate and remove the core from the solid, it was necessary to apply a large impact force to the solid after cooling the solid sufficiently. According to the method of the present invention, since a core type having high collapsibility is used, sufficient cooling and a large impact force thereafter required to remove the core type from the animal are required. Do not need. Therefore, the core 铸 type can be removed by a simple method, for example, light vibration described below. In the mold removing step 5 of the present embodiment, after about 10 minutes of pouring power, the solidified molten metal was taken out as solid. Immediately after that, the core 錡 type was completely removed by applying an impact force of IMpa or less to a 350 ° C animal by light vibration at 20Hz for less than 20sec to remove the sand. Also, according to the experiment, in the removal process 5, in the time within 5 to 20 minutes after pouring, even if the sand was removed by applying an impact force of less than IMpa at less than 30 Hz for less than 30 seconds, the core-to-metal type was completely removed from the material. Could be removed.

[0047] After removing the gate of such a substance and removing the burrs of the substance, the substance is subjected to a heat treatment. (6th (heat treatment) step 6). In the present embodiment, the gate and burrs of the object are removed before the heat treatment of the object, but may be carried out after the heat treatment. Also in this embodiment, following the sixth (heat treatment) step 6, a core sand recovery step 7, a crushing step 8, and a mechanical regeneration step 110 shown in FIG. 1 may be added.

[0048] In the molding method using the mold 铸, the particulate aggregate and the core lump are collected only from the core 錡, so that the collected and regenerated particulate aggregate is converted into the mold 铸. It can be easily reused.

FIG. 2 (Prior Art) shown for comparison is a process diagram of a conventional method of manufacturing a product using a shell mold process described in the above-mentioned Japanese Patent Application Laid-Open No. 5-261478.

[0050] In the conventional method of Fig. 2, resin-coated sand is used. Normally, resin-coated sand is manufactured and sold by a different company from the plastic manufacturer, and therefore, the step (11) of producing the resin-coated sand is performed at a place different from the plastic manufacturing site. Therefore, even if the resin-coated sand is recovered and regenerated, it is difficult to reuse the resin-coated sand for the molding of type III, in contrast to the method of the present invention.

[0051] According to the conventional method of Fig. 2, a vegetable manufacturer heats a commercially available resin-coated sand to form a core mold (12), and replaces the molded core mold with another mold. To produce a finished mold (13) and pour the finished mold (14). Next, the core mold is removed from the mold using a sand dropping furnace (15), and the fish is sufficiently cooled (16). Then, the sand is completely removed by a knockout process (17), and the fish is heat-treated ( 18). Further, the core sand including the core lump is recovered from the knockout step 17, the heat treatment step 18 and the subsequent steps (19). The recovered core sand is subjected to crushing, roasting, and mechanical regeneration of the core mass at a resin-coated sand mill, which is usually a different place from the place where the recovery step is performed. .

It is clear that the number of steps is reduced in the method for producing a product of the present invention shown in FIG. 1 as compared with the conventional method shown in FIG. For example, in the method of the present invention (FIG. 1), the fifth step (removal of type III) 5 can be achieved by a simple step, for example, sand removal by light vibration since the type III collapses easily. However, the conventional method (Fig. 2), which does not easily disintegrate the mold (1), requires removal of the mold (15), sufficient cooling of the material (16), and knockout process (17) to remove the mold. Further, the method of the present invention does not require roasting 21 in the recovery and regeneration of the conventional method. FIG. 3 is a graph showing the relationship between temperature and time in the fifth (5-type removal) step 5 and the sixth (heat treatment) step 6 of the embodiment of the present invention. FIG. 4 (Prior Art) shown for comparison is a similar graph of a conventional step corresponding to the 铸 removal and heat treatment steps in the method of the present invention.

[0054] In the conventional method, as described above, after sufficient cooling of the animal (step 16 in Fig. 2), sand removal by the knockout step is performed (step 17 in Fig. 2). The temperature was rising again. For this reason, as shown in FIG. 4, it takes time for cooling, and also requires time and energy for reheating for heat treatment.

In the embodiment of the present invention shown in FIG. 3, after pouring at 720 ° C., immediately after removing the solid after the molten metal is solidified in mold removing step 5, the core is removed from the solid. The mold has been removed. Therefore, it is not necessary to apply a large impact after sufficiently cooling the fermented product in order to remove the core type, and the solution treatment (heat treatment) can be started immediately. Therefore, the time required for cooling can be shortened, and the time for reheating for heat treatment can also be shortened, so that energy consumption can be reduced and the number of steps can be reduced. It is not always necessary to cool foods to 100 ° C. Energy savings can be obtained by cooling to 300 ° C.

[0056] The above embodiments are merely illustrative of the present invention, and are not intended to be limiting, and those skilled in the art will appreciate that various modifications may be made without departing from the spirit and scope of the appended claims. It is clear that it can be made or deformed.

Brief Description of Drawings

[FIG. 1] FIG. 1 is a process chart of a method for producing a product according to the present invention.

[FIG. 2] FIG. 2 is a process chart of a conventional method of manufacturing a product using a shell mold process.

FIG. 3 is a graph showing a relationship between temperature and time of a substance in a mold removal and heat treatment step of the present embodiment.

[FIG. 4] FIG. 4 is a graph corresponding to the step of FIG. 3 and similar to FIG. 3 showing a step of a conventional technique using a shell mold process.

Claims

The scope of the claims

[1] a method for producing a animal,

Manufacturing a completed mold by combining the mold of the other party with at least one mold formed by the particulate aggregate;

Pouring the molten metal into the finished mold,

A process for heat-treating the animal.

[2] The method according to claim 1, wherein at least one molding die formed by the particulate aggregate is a core die, and the other die is a main die.

[3] The method according to claim 2, wherein the main mold 铸 is a mold.

[4] The method according to claim 2, wherein the main mold 铸 is a sand mold.

[5] The method according to any one of claims 1 to 4, further comprising a step of collecting the particulate aggregate, and a step of regenerating the collected particulate aggregate.

[6] The method according to claim 5, wherein the recovered and regenerated particulate aggregate is reused for a 铸 -shaped molding.

7. The method according to claim 5, wherein the step of collecting and regenerating the particulate aggregate is mechanical regeneration.

[8] The method according to any one of claims 1 to 7, wherein the metal is an aluminum alloy material or a magnesium alloy material.

[9] The method according to claim 8, wherein the heat treatment power is ST6 treatment or T7 treatment.

[10] The method according to any one of claims 1 to 7, wherein the substance is a substance made of iron, steel, or an iron-based metal alloy.

[11] The method according to any one of claims 1 to 7, wherein the metal is a copper alloy material.

[12] The method according to any one of claims 1 to 11, wherein the step of removing the 铸 pattern is performed.

And applying vibration to the 铸 type.

[13] The method according to claim 12, wherein the vibration is applied to the mold (5) from 5 minutes after pouring.

A method comprising applying an impact force equal to or less than IMpa to the type で for less than 30 seconds at less than 30 Hz within a time period of 20 minutes or less.

[14] A method for producing a animal,

Forming an aggregate mixture by mixing at least one particulate aggregate, at least one water-soluble binder, and water;

The aggregate mixture is agitated and foamed, and the foamed aggregate mixture is filled in a space for mold making, and the moisture in the filled aggregate mixture is evaporated to solidify the aggregate mixture, and the aggregated particles are formed. A step of molding a core 铸 type with aggregate;

A step of combining at least one of the core mold and the mold to form a completed mold; and pouring a molten aluminum alloy into the completed mold.

Removing the core mold from the molten metal during the cooling period of the solidified solid;

Subjecting the aluminum alloy article to a T6 or T7 heat treatment.

[15] The method according to any one of claims 1 to 14, wherein the at least one water-soluble binder is at least one of polybutyl alcohol and a derivative thereof,

Alternatively, the method is at least one of starch and a derivative thereof.