JPH03184636A - Warm forming method for aluminum plate material - Google Patents

Abstract

PURPOSE:To obtain the products of highly accurate dimension with the inexpensive die of long service life by heating the Al plate material up to the specific temperature, using the concrete die and executing the warm press forming. CONSTITUTION:The Al plate material 3 is heated up to the temperature of 150 deg.C-300 deg.C, the press forming is executed by descending and/or ascending of the die arranged with the concrete male die 1 and the female die 2. Therefore, the die is inexpensive and has a long service life, and because the forming is executed in the state of excellent plastic forming property of Al plate material, so the products with highly accurate dimension, even if the forming products has complicated shape, are obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a warm forming method for aluminum plate materials, and particularly to a method suitable for forming aluminum ship hulls and the like.

[Conventional technology] Conventionally, large molded objects such as ship hulls made of aluminum plates have been produced by cutting the plates, fixing them to ribs, and then bending and welding them manually, or by cutting the plates in advance using rolls, a bender, etc. A method of bending and then welding is used. In addition, in the case of relatively small hulls, the stretch form method is adopted, and a processing method using hydraulic pressure is also being considered, as shown in Japanese Patent Application Laid-Open No. 62-93034.

With methods that use a lot of welding, it is difficult to create a three-dimensional shape like a ship's hull, requiring a lot of man-hours and a long construction period. Nevertheless, it is more expensive and less economical than FRP hulls, and its appearance is also inferior to FRP hulls.

In addition, in the case of the stretch form method, the stretch form equipment is expensive and requires processing skills, so it is less economical and is limited to relatively small ship hulls with thin plate thickness, for example, 1 to 2 car thickness. There is.

Also, JP-A-62-93 (184 and references, Matsubara, Mende: "Development of Aluminum Ship Construction Technology by Hydroforming" Light Metal Welding Vol. 1.24 (198B) k2 p,
The hydroforming method shown in 59 to 64 has limitations on the shape of the ship, and the cost of forming equipment increases as the ship becomes larger, and it also requires combination with welding methods, so there are still problems in practical application. be.

[Problems to be solved by the invention] This invention solves the problems of the prior art as described above,
The first objective is to develop an economical forming method for aluminum plate materials, and the second objective is to develop a processing method that has an excellent appearance and marketability, and is also applicable to thick plates. The third purpose is to realize a processing method.

More specifically, the aim is to develop a method suitable for forming aluminum ship hulls.

[Means for Solving the Problems] In order to achieve the above object, the Al 1, minilam board forming method of the present invention includes an aluminum plate material heated at 150°C to 30°C.
It is characterized by heating to a temperature of 0°C and pressing with male and female molds made of concrete. Furthermore, in the above method, the present invention provides a method of supporting an aluminum plate material on a blank holder, and a heat-resistant rubber or
This method includes a method of bringing an aluminum material into contact with a male mold and/or a female mold using an elastic body made of a combination of the aluminum material and heat-resistant fibers.

The present invention will be described below, including examples. The temperature of the aluminum plate material during processing is 150°C to 300°C. The method may be by heating in advance using a furnace, burner, electric heat, etc., or by heating on a mold.

The material of the male and female molds shall be concrete, but if a blank holder is used, the contact surface between the blank holder and the female mold may be concrete or steel plate, and steel may be used as reinforcement for the male and female molds as necessary. It is natural to do so.

It is also possible to use a sandwich-like elastic body with either a male mold or a female mold, heat-resistant fibers, heat-resistant resin, or heat-resistant rubber on the surface in contact with the plate material, and heat-resistant rubber or urethane rubber as the elastic body on the opposite side. , heat-resistant rubber alone can also be used.

Heat-resistant fibers, heat-resistant resins, and heat-resistant rubbers include glass wool fibers, reticulated Teflon resin, polyimide resin, silicone rubber, and fluorine rubber.
The thickness should be such that the temperature does not exceed 00°C, and when heat-resistant rubber is used as the elastic body, the thickness should be such that the surface temperature does not exceed 280°C.

The surface temperature of the male and female molds made of concrete is 280℃.
If the temperature is above 300℃ or less, the mold life will be short, so 260℃
The following is desirable, and heat-resistant fibers or heat-resistant resin are used between the mold and the material.
It is better to sandwich heat-resistant rubber. In this case, heat-resistant fibers, heat-resistant resins, and heat-resistant rubbers such as Teflon sheets, glass wool fibers, reticulated Teflon resins, polyimide resins, silicone rubber, and fluorine rubber are good.

The alloys applied to aluminum ships are mainly A, Q-Mg alloys (JIS,
5052.5083 etc.).

Through press forming, it is possible to produce plates with a thickness of 3 mm to 7 m.
When the temperature is between 50°C and above and 300°C and below, the elongation of aluminum plate material increases and the strength decreases compared to room temperature.
In other words, since the plastic workability is improved, the forming process of thick plates becomes easier. This is illustrated in an experimental example as shown in FIG.

Press-forming an aluminum plate stabilizes and improves its shape, but due to the main shape, the aluminum plate can be
When processed by heating to a temperature of 0℃ or higher to 300℃ or lower,
Since the yield strength is lower than room temperature in this temperature range, the moldability is further improved and the commercial value is increased.

Male and female molds and blank holders made of concrete are used as cheap and simple molds in room temperature presses.
However, it is not used at temperatures above 150°C and below 300°C.

As a result of examining the method of using this at temperatures above 150℃ and below 300℃, we found that if the temperature exceeds 300℃, minute cracks are likely to occur on the surface of the concrete, and the service life will be short.
The following is a PI function that can be used several times, and if it is kept below 260℃, it can be used without any problems.Generally, in the case of ship hulls, it is rare to use it more than a few times, so industrially it is
As long as the temperature is between 50° C. and above and 300° C. and below, male molds, female molds, and blank holders made of inexpensive concrete can be used.

Concrete can be used without any problems if it is below 260℃, and if it is used many times, the material temperature should be lowered to 260℃.
℃ or less, or set the material temperature to 300℃ or less and use a heat-resistant Teflon sheet, glass wool fiber, reticulated Teflon resin, or heat-resistant rubber as a heat insulating material between the male mold or female mold made of concrete, the blank holder, and the aluminum plate. A method of sandwiching a silicone rubber sheet or a fluorine rubber sheet may be used, and the manufacturing cost of the hull can be reduced by using a male or female mold or a blank holder made of inexpensive concrete.

A method of manufacturing a ship's hull by pressing a combination of a male or female mold made of concrete and a combination of heat-resistant fiber or heat-resistant rubber and urethane rubber is to press a combination of heat-resistant fiber or heat-resistant rubber and urethane rubber for each male or female mold. It is a cheaper method because the rubber combination can be used many times.

An example of press forming an aluminum hull will be described below. Fig. 1, which shows the basic configuration of the present invention, shows a concrete male mold 1 (upper part in the figure) and female mold 2 (lower part in the figure) arranged with an aluminum plate in between, and press forming is performed by raising and/or lowering the molds. It will be done. FIG. 2 shows an example in which a concrete male mold 1 and a female mold 2 are arranged with an aluminum plate 3 supported at the top end of a concrete blank holder 4 that can be moved up and down.

FIG. 3 shows an example in which a heat-resistant fiberboard 5 is placed on top of the fixed female mold 2, an aluminum plate 3 is placed on top of the heat-resistant fiber board 5, and the cavity of the female mold 2 is further lined with a urethane rubber sheet.

[Effects] The present invention uses a concrete mold to perform warm press forming of an aluminum plate at a temperature in the range of 150 to 300°C, so the mold is inexpensive and has a long life, and the aluminum plate has excellent plastic formability. Since the molding is carried out in the same state, it is possible to obtain a product with good dimensional viscosity even if the molded product has a complex shape, which solves the problems of conventional press molding methods. Particularly suitable for press forming thick plates is the square shape, which is suitable for economical forming of large ship hulls.

[Brief explanation of drawings]

Figure 1 is a schematic diagram showing the method of press forming an aluminum plate using a concrete male mold and a female mold, Figure 2 is a schematic diagram of an example in which a concrete blank holder is arranged, and Figure 3
The figure is a schematic diagram of an example in which a heat-resistant plate is placed on one side of an aluminum plate and an elastic body is placed inside the concrete female mold on the corresponding side. FIG. 4 is an experimental example showing the relationship between temperature, strength, and elongation of an aluminum alloy plate material. Applicant Sky Aluminum Co., Ltd. Figure 1 Temperature procedure amendment (voluntary) February 7, 1990 1゜2゜3゜

Claims (4)

[Claims] (1) A method for warm forming an aluminum plate, which comprises heating the aluminum plate to a temperature of 150°C to 300°C and pressing it using male and female molds made of concrete. (2) A method for warm forming an aluminum plate, which comprises heating the aluminum plate to a temperature of 150° C. to 300° C., supporting it on a blank holder, and pressing it with male and female molds made of concrete. (3) Aluminum plate material is heated to a temperature of 150°C to 300°C and pressed with a male mold and/or female mold made of concrete and an elastic body made of heat-resistant rubber, urethane rubber, or a combination of these and heat-resistant fibers. A warm forming method for aluminum plate material, characterized by: (4) The method for warm forming an aluminum plate according to any one of claims 1 to 3, wherein the object to be formed is a ship's hull.