JPS6356320A - Forming die for sheet metal made of high strength cement - Google Patents

Abstract

PURPOSE:To manufacture the forming die for sheet metal having excellent accuracy of the forming face and being strong by using the high strength cement hardened body of the specific compression strength as the die material. CONSTITUTION:The kneading body of the high strength cement hardened body of the compression strength of >=1,000kgf/cm<2> is made by combining, etc., with a cement respectively those which add a plaster group high strength admixture, those which subject a mortar, etc., to an autoclave treatment or a microfine powder and high performance water reducing agent. The kneading body 3 is cast to the wooden pattern mold 1 preparing a frame 2, etc., on the periphery. The high strength cement mold 4 for sheet metal can be manufactured by curing the kneading body 3 with its releasing from the original mold 1 after its hardening. This mold 4 is excellent in its solidity in addition to the transferability. In case of the above hardening bodys compression strength being <1,000kgf/cm<2> the form destruction of a crack, notch dent, etc., is caused at the sheet metal forming time.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention provides a high-strength cement mold with a compressive strength of 1.000 kgf/cm2 or more for manually molding a metal plate to obtain a product. Regarding.

<Conventional technology and its problems> Conventionally, materials for forming molds (hereinafter referred to as sheet metal molds) for manually forming metal plates to obtain products have been required to be robust (high strength), precision Metals, resins, gypsum, cement, etc. have been used for reasons such as the ability to obtain products with high quality, low cost, and short farming period, but none of these materials has been satisfactory.

For example, aluminum laminate, ini-lead-based low separation point alloys, and the like have been used as materials for forming molds for metal sheet metals. However, although such metals have excellent robustness, they have a large shrinkage value when hardened, and when used as molds for sheet metal, the processing costs for precision finishing are high, the manufacturing time is long, and processing requires skill. It had the disadvantage of being cheap. In addition, sheet metal molds made of resin or gypsum provide good transferability during production and the production period is short, but they have drawbacks such as poor robustness and chipping when the metal plate is knocked out. Furthermore, cement is a simple material that can be molded at room temperature, but as a mold for sheet metal, it usually has a compressive strength of about 6D01ψf/cm, and its durability is poor. The drawback was that the transferability during production was poor.

The present inventors investigated various sheet metal molds that are inexpensive, have excellent molding surface precision, and are robust, and found that
It was discovered that a mold made of high-strength cement with a compressive strength of 1.000 k17f/cm" or more has a surprising effect as a mold, and the present invention was completed.

3) Means for Solving the Problems> That is, the present invention is a high-strength cement sheet metal forming mold made of a hardened high-strength cement having a compressive strength of 1.000 kgf/cm2 or more.

The present invention will be explained in more detail below.

The high-strength cement mold for sheet metal used in the present invention is basically one based on cement, one to which a gypsum-based high-strength admixture has been added, mortar etc. that has been autoclaved, or one made of ultra-fine powder. It is obtained by combining high-performance water reducing agents with cement, and is made from a high-strength hardened cement material that exhibits a compressive strength of 1,000 Qf/am2 or more. This sheet metal mold can be manufactured by pouring into a master mold and inverting it.

In particular, sheet metal forming molds made of cementitious materials, ultrafine powder, high-performance water reducing agents, and high-strength cement hardened bodies whose main components are water are not only strong and hard, but also have excellent surface transferability and ease of forming. The characteristics are the best.

The cementitious materials referred to here include cements such as kneelite, C3S, normal, early strength, super early strength, white or sulfate resistant, citron portland cement, alumina cement, etc. alone or in combination, as well as blast furnace slag and fried materials. Commonly used is 7'C mixed cement mixed with ash or the like. Also, blast furnace slag may be used in combination with an alkaline stimulant such as hydroxides, carbonates, and bicarbonates of alkali metals and/or alkaline earth metals.

Furthermore, it is also possible to use in combination a material with improved shrinkage characteristics using expanded cement as a menthol material, a material with the required strength developed in a short time using rapid hardening cement, and a gypsum-based high-strength admixture.

The expanding component of the expanding cement is an Etrin guide type, such as "C8A÷2" manufactured by Denki Kagaku Kogyo Co., Ltd.
0'' or calcined CaO is preferable, and among calcined CaO, 1
, fired at 100-1,300°C, with an average crystal diameter of 1
It is preferable to have a particle size of 0μ or less.

The quick-hardening component of quick-hardening cement is preferably calcium aluminate-based, such as alumina cement, a combination of alumina cement and gypsum, Denka ES manufactured by Denki Kagaku Kogyo Co., Ltd., and Onoda Cement Co., Ltd.
The product name ``Jet Cement'' is used.

In addition, the high-strength admixture is preferably a gypsum-based one, for example, manufactured by Denki Kagaku Kogyo Co., Ltd. [Denka Σ-1000J,
Products manufactured by Nippon Cement Co., Ltd. such as Asano Super Mix J are effective.

The ultrafine powder that can be used here has an average particle size that is at least one order of magnitude smaller than that of cementitious materials (average particle size of about 10 to 60μ), and those with an average particle size that is two orders of magnitude smaller have better flow characteristics of the mixed material. It is preferable from the aspect. Specifically, silica dust (silica fume) and siliceous dust, which are produced as by-products during the production of silicon, silicon-containing alloys, zirconia, etc., are particularly suitable, as well as calcium carbonate, silica del, opalescent silica, fly ash, and blast furnace slag. , titanium oxide, aluminum oxide or finely pulverized cementitious materials can also be used. %, the use of ultrafine powder obtained by pulverizing opalescent silica, fly ash, and blast furnace slag by using a classifier and a pulverizer in combination is effective in improving hardening shrinkage.

The amount of ultrafine powder used is preferably 40 to 5 parts by weight based on 60 to 95 parts by weight of the cementitious material, and more preferably 35 to 10 parts by weight based on 65 to 90 parts by weight of the cementitious material. If the amount of ultrafine powder used is less than 5 parts by weight, the effect of developing high strength will be small, and if it exceeds 40 parts by weight, the fluidity of the mixed material will decrease significantly, making it difficult to mold.
Moreover, the strength development is also insufficient.

In addition, the high-performance water reducing agent referred to here is a surfactant with a large dispersion ability that does not cause too much delay in setting or excessive air entrainment even when added to cement, such as naphthalene sulfonic acid formaldehyde condensate. Examples include salts of melamine sulfonic acid formaldehyde, salts of condensates, and those whose main components are high molecular weight trigenin sulfonates, polycarboxylate salts, and the like. Conventionally, the amount of high-performance water reducing agent used is 0.3 to 1% by weight as a solid content based on cement, but in the present invention, it is preferably added in a larger amount, and 1 to 5% by weight. Parts by weight are more preferred. A high-performance water reducing agent is necessary to obtain a kneaded product with a low water/(cementitious material powder) ratio (hereinafter referred to as water/powder ratio)! However, if it exceeds 10 parts by weight, it will adversely affect the curing reaction. When using such a high-performance water reducer, it is necessary to combine ultrafine powder with a water/powder ratio of 2.
Even if the amount is less than 5%, a fluid mixed material that can be molded by conventional methods can be obtained.

The water used here is necessary for molding, and in order to obtain a high-strength hardened cement product, it is sufficient to use as little water as possible.
00 parts by weight, preferably 10 to 60 parts by weight of water, and 12 parts by weight of water.
-25 parts by weight is more preferred. If the amount of water used is more than 30 parts by weight, it will be difficult to obtain a high-strength hardened cement product, and if it is less than 1 part by weight, it will be difficult to perform ordinary molding such as pouring. Note that compression molding and the like is not limited to this, and molding is possible even when the amount is less than 10 parts by weight. It is also possible to use a molding method commonly used for cement concrete, such as extrusion molding.

Aggregate can also be used in addition to the 10HU2 material.

The aggregate may be one that is generally used when mixing concrete in the civil engineering and construction field, but it should be a hard one, specifically one with a Mohs hardness of 6 or more, preferably 7 or more, or a Knoop indenter hardness of 700 kg/ m♂ or higher, preferably 80
0kl? It is preferable to use aggregates selected based on any of the criteria 2 or higher because the strength can be significantly improved. This dam, phenazite, spinel, beryl, full curb, tungsten carbide, ferrosilicon nitride, silicon nitride, fused silica, fused silica, fused magnesia, silicon carbide and cubic boron nitride, etc. and machinable stainless steel, There are metals such as iron powder and iron balls.

The amount of aggregate to be used is usually selected to be within twice the STL amount of the powder. However, this limitation does not apply in the case of special forming methods such as pre-packed construction method and post-packed construction method.

In addition to the above-mentioned materials, various fibers and steel can also be mixed.

Fibers include fibers produced by cutting cast iron, steel fibers, stainless steel fibers, various natural or synthetic mineral fibers such as asbestos and alumina fibers, carbon fibers, glass fibers, and polypropylene, vinylon, acrylonitrile, and cellulose. Examples include natural or synthetic organic fibers. In addition, copper rods and F
It is also possible to use an RP rod, which is indispensable especially in the case of large sheet metal molds.

In addition, it is also possible to add so-called solid lubricants, such as molybdenum disulfide and orthogonal boron nitride, to provide other functions, such as sliding properties, and even oil-absorbing carbon, etc. It is also possible to use

In addition, it is also possible to mix in materials that provide special properties such as thermal conductivity and electrical conductivity.

Any method may be used for mixing and kneading the above-mentioned materials as long as they can be mixed and kneaded uniformly, and the order of addition is not particularly limited.

The mold for sheet metal of the present invention is obtained by casting a pre-obtained mixed material into a master mold with a frame etc. prepared around it, and after curing the mixed material, removing it from the master mold and curing it. It can be manufactured very easily without the need for post-processing. Note that bubble formation on the casting surface should be taken into consideration, and it is preferable to remove the bubbles by vacuum casting after vacuum kneading or by degassing before casting.

Furthermore, when casting the sheet metal mold according to the present invention,
It is also possible to cast only the molded part in contact with the metal plate with the kneaded material according to the present invention, and to cast the remaining part with an ordinary cement kneaded material before the mixed material according to the present invention hardens and dries. .

Various curing methods are possible for curing the molded product, including room temperature curing,
Any of the methods of normal pressure steam curing, high temperature and high pressure curing, and high temperature curing can be employed, and if necessary, a combination of these methods can be used to obtain a high strength hardened cement body.

The sheet metal forming die easily produced by the above method has excellent surface transferability and excellent rigidity by exhibiting a compressive strength of 1,000 kli'f/cm2 or more. If the compressive strength is less than 10 kgf/cm2, mold failure such as cracks, chips, and dents will occur during sheet metal forming.

Next, a sheet metal forming method by manual processing of a metal plate using the sheet metal forming mold of the present invention will be described.

The metal sheets to be processed by hand are ordinary sheet metals that are the same as the target metal sheets, such as hot-rolled thin steel sheets, cold-rolled steel sheets, galvanized iron sheets, tinplate sheets, stainless steel sheets, etc., and copper sheets. including non-ferrous metal plates.

If the metal plate is too thick, it will be difficult to form it by hand.
The upper limit of the plate thickness is about 2 mm.

Manual processing is carried out by bringing a metal plate into contact with the forming surface of the sheet metal mold of the present invention, and then striking the metal plate with a spatula made of oak or Bakelite using a sheet metal hammer or a wooden hammer. The work method is similar to that of sheet metal work. Therefore,
Sheet metal hammers are used in various shapes such as karakami, single-eyed, eboshi, raised, and potato shapes for drawing and bending work, and similarly wood hammers are used in karakami and double-light shapes. . In addition, a chisel for correcting bends, a clapboard for bending and leveling, a Katakana blade for folding edges, a leveling anvil for leveling and folding edges, and a wrinkle remover for straightening wrinkles. Tools of the gods, such as sticks, are also used as needed. It is of course also possible to set the metal plates formed by these operations into the sheet metal molds of the present invention and join them by brazing with solder, welding with gas or arc, riveting, etc.

<Example> The present invention will be specifically explained below using Examples.

Embodiment FIG. 1 shows the manufacturing process of a sheet metal mold of the present invention for manually molding an automobile door inner panel.

First, a wooden prototype 1 was produced (process A). Then it is placed in frame 2 and the surface is coated with mold release agent rQZ-5TJ.
A mixture manufactured by Nippon Ciba Geigy Co., Ltd. was sprayed to cast a hybrid material 3 according to the present invention. The kneaded material is made using the following materials.
The mixture was vacuum kneaded using a vacuum omnimixer 0M-30Vj manufactured by Chiyoda Giken Co., Ltd., and then cast (Step B). After curing in humid air at 20° C. for one day, the hardened sheet metal mold 4 was demolded (Step C).

The main curing conditions were as follows.

Materials used and curing conditions> ■ Materials used: Cement: White cement, manufactured by Chichibu Cement Co., Ltd., 80
Parts by weight Ultrafine powder Nijirikahium, manufactured by Japan Heavy and Chemical Industry Co., Ltd.
20 parts by weight Aggregate: Niketsu rock, from the Great Wall of China, particle size 0.3-1.2 mm, 120 parts by weight High performance water reducing agent: B Salt of naphthalene sulfonic acid formalin condensate [Selfflow 110PJ No. - Manufactured by Kogyo Seiyaku Co., Ltd., 2 parts by weight Water: Tap water, 19 parts by weight Fiber: Steel fiber by chatter cutting, Kobe Foundry Works Co., Ltd.
2 mm long, 7 parts by weight Main curing conditions: Cured in humid air at 50°C for 1 day.

■ Materials used: Cement, biwhite cement, manufactured by Chichibu Cement Co., Ltd., 91
Parts by weight Gypsum-based high-strength admixture: Denka Σ-1000J manufactured by Denki Kagaku Kogyo Co., Ltd., 9 parts by weight High performance water reducing agent: [Cellflow 110PJ Dai-Kogyo Seiyaku (
Co., Ltd., 2 parts by weight Aggregate: [Nikko Silica Sand J O, 15-25 mm, Yotetsu Mining Co., Ltd., 100 parts by weight Water: Tap water, 27 parts by weight Non-curing conditions: 2D'028 days.

■ Material used: Cement: “Ordinary cement” manufactured by Denki Kagaku Kogyo Co., Ltd., 1
[ ] 0 parts by weight High performance water reducing agent: "Cellflow 110PJ Dai-Kogyo Seiyaku (
Aggregate: Natural sand, Sagami-produced river sand, 5 kats or less, 200 parts by weight Water: Tap water, 26 parts by weight Motosugao Conditions: Temperature increase/decrease rate of 10°C/hour, 180°C,
Autoclave curing was performed under the holding conditions of 1Q k17f/cm''('f-di pressure) and 10 hours.

A cold-rolled steel plate 5 (spa-2 (JIS a 3310) plate thickness 0.8+oI□) is brought into contact with the sheet metal mold 4 obtained as described above as shown in FIG. The inner panel of an automobile door was made from sheet metal by hitting the wooden piece with a sheet metal hammer.

In addition, the compressive strength, bending strength, and hardness of high-strength cement hardened bodies manufactured under the same conditions were measured, and the results are also listed in the table along with the sheet metal work results using sheet metal forming molds made of high-strength cement (hereinafter referred to as high-strength cement molds). did.

For comparison, the table shows the results of sheet metal work when sheet metal molds were made of plaster, resin, low-temperature alloy, and ordinary cement.

<Effects of the Invention> The high-strength cement mold of the present invention can be produced at a low cost, has a good transfer surface, is excellent in robustness, does not cause mold damage even when hand-processed sheet metal work is performed, and can be used with metals. It is effective as a sheet metal mold for forming a plate by hand to obtain a product.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of the process of manufacturing the high-strength cement mold of the present invention. That is, a wooden master mold is placed in step A, a frame is set around the wooden master mold in step B, a kneaded material is cast there, and the mold is hardened and removed to form a high-strength cement mold in step C. be. Further, FIG. 2 is a plan view of the high-strength cement mold of the present invention, and FIG. 6 is a sectional view thereof. Code 1: Wooden prototype 2: Frame 3: Mixer 4: High-strength cement mold 5: Cold rolled steel plate

Claims (1)

[Claims] High-strength cement sheet metal mold made of hardened high-strength cement with a compressive strength of 1,000 kgf/cm^2 or more