JPH0760381A - Method for forming foil - Google Patents

Abstract

PURPOSE:To simultaneously form a number of foils of complicated shapes by placing a laminated body of foils in a sealed body consisting of a dummy die and a super-plastic material, rising the temperature while executing the evacuation, and loading the gas pressure being fit to the desired shape. CONSTITUTION:A laminated body 8 of foils is sealed together with a dummy die 9 by a face plate 6 and a rear plate 7 to make a sandwich plate, and this sealed body 10 is placed between an upper die 3 and a lower die 4. The temperature is risen while evacuating the sealed body 10 and the inside space, and the sealed body is kept at the constant temperature, and the prescribed pressure is applied to the upper die 3 to closely attach the upper die 3 to the face plate 6 of the sealed body 10 through the seal 12. Then, the forming gas is introduced through a gas passage 5 to be provided in the upper die 3, the gas pressure is applied from the top surface of the face plate 6 to continue the pressure application until the sealed boy 10 is fit to the shape of the lower die 4. After forming, the sealed body 10 is taken out and disassembled, and the foils are peeled one by one.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for simultaneously forming a large number of foil materials, and for example, for forming a large number of matrix metal foils used in the case of manufacturing a component having a complicated shape such as an engine part from a metal matrix composite material. Regarding the preforming method.

[0002]

2. Description of the Related Art A conventional foil material having a complicated shape having a three-dimensional curved surface is formed by multi-step hot sizing.

[0003]

In forming a foil material in a complicated shape by hot sizing, hot sizing is required a plurality of times to form a wrinkle without forming wrinkles. Therefore, a plurality of mold sets (each stage) are required. Yes, each set requires two upper and lower molds. That is, 10 molds are required for molding in 5 steps. Further, the heating is performed 5 times, and in this case, when the foil material is a material that is easily oxidized such as Ti or Ti alloy, the plate thickness is thin (for example, 0.
(1 mm plate thickness) 1 mm plate thickness or more, which is relatively thick, is not a problem.

In view of the above-mentioned state of the art, the present invention has the above-mentioned problems with the complicated shape forming of a foil material by hot sizing (that is, many molds are required, the number of heating cycles is large, and the cost is high) That is, the embrittlement of the foil material is likely to occur) and a plurality of (for example, 50) foil materials are molded into a complicated shape having a three-dimensional curved surface by one heating with one mold. It is the one we are trying to provide.

[0005]

According to the present invention, a laminated body in which a plurality of foil materials are stacked is formed in a sealed body formed by a dummy mold and two superplastic materials and capable of vacuuming the inside. A first mold having a gas introducing passage for pressurizing and a second mold having a desired shape
When the temperature of the sealed body reaches a predetermined temperature by pulling a vacuum inside the sealed body, a pressure is applied to the first die to apply the pressure to the first die. In order to prevent the gas introduced from the molding pressurizing gas passage from leaking to the outside,
The molding pressurizing gas is introduced from the molding pressurizing gas introduction passage of the first mold so as to maintain the state between the mold and the front plate of the sealing body. A foil characterized in that the same gas pressure is applied until the stopper fits into the shape of the second mold to form the sealing body, and then the formed sealing body is taken out and disassembled to obtain a forming foil material. It is a method of forming a material.

[0006]

Now, the state of molding stress during molding by gas pressure molding using the gas introduced from the molding pressurizing gas introduction passage provided in the first mold (upper mold) will be considered with reference to FIG. The molding conditions and assumptions are as follows. 〇 Pressure of forming pressurizing gas: P (gauge pressure) 〇 Thickness of front plate 6 sandwiching foil laminate 8 at point A: t ₁ 〇 At point A of front plate 6 sandwiching foil laminate 8 Stress: σ ₁ 〇 Curvature in two directions orthogonal to point A of front plate 6 sandwiching foil laminate 8: r ₁ , r ₂ 〇 Thickness of back plate 7 sandwiching foil laminate 8 at point A : T ₂ o Stress at point A of back plate 7 sandwiching foil laminate 8: σ ₂ Curvature in two directions orthogonal to point A of back plate 7 sandwiching foil laminate 8: r ₁ , r ₂ Note that the deformation resistance of the foil laminate 8 is smaller than that of the sandwiched front plate 6 and back plate 7, so it can be ignored, and the foil laminate 8 maintains the same shape as the sandwiched front plate 6 and back plate 7. It will transform.

The pressures P ₁ and P ₂ are expressed by the following equations: P ₁ = σ ₁ t ₁ (1 / r ₁ + 1 / r ₂ ) ... Pressure corresponding to the stress generated on the front plate 6. P ₂ = σ ₂ t ₂ (1 / r ₁ + 1 / r ₂ ) ... Pressure equivalent to stress generated in back plate 7 Further, the following equation holds: P = P ₁ + P ₂ Therefore, ΔP = P− A pressure corresponding to P ₁ = P ₂ is applied to the foil stack 8. That is, the laminated foil 8 is sandwiched between the front plate 6 and the back plate 7 to be sandwiched by the pressure of P ₂ and simultaneously with the sandwich plate, the second mold (lower mold).
It deforms until it follows the mold shape of. Therefore, the laminate 8 of foils can be formed without forming wrinkles in a complicated shape having a three-dimensional curved surface and while maintaining a clean atmosphere.

[0008]

Embodiment 1 An embodiment of the present invention will be described with reference to FIG. In FIG. 1, A is a hot press machine, 1 is a press upper die, 2 is a press lower die, 3 is a first die (upper die) used in forming a foil, and 4 is a second die (lower die). Both types are SU
The material is S304. A molding pressurizing gas passage 5 is provided in the upper die 3, and the shape of the lower die 3 is a blade shape as shown in the drawing. 6 is a front plate and 7 is a back plate. Both plates are made of Ti-6Al-4V, the front plate 6 has a thickness of 2 mm, and the back plate 7 has a thickness of 1 mm. 8 is a foil to be formed (foil thickness: 130 μm, material: Ti-15
V-3Cr-3Sn-3Al) is a laminated body in which a release agent is applied to both surfaces and 33 sheets are stacked. This laminated body 8 is a dummy type (material: SUS304, plate thickness: 10 mm, width: 35
mm) 9, the front plate 6 and the back plate 7, and is sealed inside the sealing body 10. The sealing body 10 is provided with a vacuum suction hole 11 for vacuuming the inside. 12
Is a seal for preventing the gas supplied from the molding pressurizing gas passage 5 from leaking between the upper mold 3 and the front plate 6 of the sealing body 10.

The procedure for forming the foil will be described below. (1) As shown in FIG. 1, a laminate 8 of foil is sealed together with a dummy mold 9 by a front plate 6 and a back plate 7 which are sandwich plates, and this sealing body 10 is divided into an upper mold 3 and a lower mold 4. Install in between. (2) The sealing body 10 and the inside are evacuated through the vacuum suction hole 11 to raise the temperature, and after reaching 880 ° C., the temperature is maintained at that temperature and the upper mold 3 is pressure-loaded to press 50 tons. The upper die 3 and the front plate 6 of the sealing body 10 are brought into close contact with each other via the seal 12 so that the molding pressurizing gas supplied in the next step does not leak outside between the upper die 3 and the front plate 6. (3) Next, the molding pressurizing gas is introduced through the molding pressurizing gas passage 5 provided in the upper mold 3, the gas pressure is applied from the upper surface of the front plate 6 of the sealing body 10, and the sealing body 10 moves downward. Pressurize until conforming to the shape of the mold 4. An example of the pressurization pattern is shown in FIG. (4) After molding, the sealing body 10 is taken out and disassembled, and the foil materials are peeled off one by one. FIG. 4 shows an example of the shape of one sheet of the formed foil material.

(Example 2) This example differs from Example 1 only in the foil laminate, and the foil laminate 8 is made of Ti.
-15V-3Cr-3Sn-3Al foil (hereinafter abbreviated as Ti foil) and a laminate of SiC fiber woven,
A release agent is applied only to the outermost surface of the Ti foil. The structure of this laminated body 8 is shown in FIG. That is, as shown in FIG. 5, five Ti foils were laminated on both sides, and 20 layers of SiC fiber woven and Ti foil were alternately laminated between them. The SiC fiber woven used here is US TEXSTRON SPCIAL MATERI.
It was interwoven with Mo foil by SCS-6 (trademark) manufactured by ALS.

After molding in the same manner as in Example 1, SiC fiber and T
It is a blade-shaped composite material preform made of i.
This was HIPed at 900 ° C., 1500 atm. When it is compounded and molded in 2 hours, it becomes a blade of a metal matrix composite material.

[0012]

EFFECTS OF THE INVENTION The method for forming a foil material according to the present invention makes it possible to form a complicated three-dimensional curved surface in a single forming step without causing embrittlement such as oxidation of the foil material. Can be formed into a shape.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an example of a method for forming a foil material according to an example of the present invention.

FIG. 2 is an explanatory view of stress balance during molding of the foil material of the present invention.

FIG. 3 is an explanatory view of a forming pressure pattern in a method for forming a foil material according to an embodiment of the present invention.

FIG. 4 is an external view of a Ti foil formed according to an example of the present invention.

FIG. 5 shows a foil material to be molded according to another embodiment of the present invention with S.
The block diagram of an iC fiber woven laminated body.

Claims (1)

[Claims] 1. A laminated body in which a plurality of foil materials are stacked is sealed in a sealed body formed of a dummy mold and two superplastic materials and capable of vacuuming the inside, and the laminated body. Interposing a sealing body containing therein a first mold having a molding pressure gas introduction path and a second mold having a desired shape,
When the inside of the sealing body is evacuated and the temperature is raised to reach a predetermined temperature, a pressure is applied to the first mold to apply the pressure to the first mold.
In order to prevent the gas introduced from the molding pressurizing gas passage of the mold from leaking to the outside, a seal is formed between the first mold and the front plate of the sealing body, and the state is maintained.ゝ Molding pressurizing gas is introduced from the molding pressurizing gas introduction passage of the first mold, and the same gas pressure is applied until the sealing body conforms to the shape of the second mold to mold the sealing body. After that, the molded sealing body is taken out and disassembled to obtain a molded foil material.