JPH0732120A - Segmental die for forging of molten metal which lessens formation of thermal stress - Google Patents

Abstract

PURPOSE:To provide the segmental dies for forging of molten metal which lessens the generation of crack occurring in a thermal stress. CONSTITUTION:The segmental dies for forging of molten metal are composed of a blind frame 1, a cavity plate material 2 which is disposed like a cap at the top end of this frame 1 and forms a cavity for forging of the molten metal on its upper surface and plural supporting members 3, of which the top end faces and bottom end faces come into contact with the rear surface of the cavity plate material 2 and the base of the frame 1, respectively, and which are disposed adjacently to each other, in the space of the frame 1. The segmental dies are usable over a long period of time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a split mold for forging a molten metal, in which generation of thermal stress is extremely small and therefore cracking does not occur and a long service life is possible.

[0002]

2. Description of the Related Art Conventionally, as a die for metal pressure casting such as a molten metal forging method, a die casting method and a low pressure casting method, an integrated die formed by electric discharge machining or cutting is widely used rather than a block material. It is used.

[0003]

On the other hand, in recent years, there is a strong demand in the field of molten metal forging to improve productivity, and accordingly, operation under severe conditions is inevitable.

Therefore, the thermal stress generated in the mold used tends to be high, but in the above-mentioned conventional mold, it is possible to avoid the occurrence of a large thermal stress locally due to the fact that the mold is integrated. However, due to this, microcracks are likely to occur, and the accumulated cracks reach the service life in a relatively short time.

[0005]

[Means for Solving the Problems] Therefore, the inventors of the present invention conducted a study to develop a metal melt forging die with less thermal stress from the above viewpoints, and as a result,
A bottomed frame body, a cavity plate member provided in a lid shape on the upper end portion of the frame body and forming a molten metal forging cavity on the upper surface, and an upper end surface and a lower end surface in the space of the frame body, respectively. If it is composed of a plurality of support members that are in contact with the back surface of the plate and the bottom surface of the frame and are adjacent to each other, the thermal stress generated in the mold is dispersed to each structural member, and the thermal stress is concentrated. Therefore, we obtained the research result that cracks can be prevented.

The present invention has been made on the basis of the above research results, and has a bottomed frame, a lid-like structure provided on the upper end of the frame, and a molten metal forging cavity formed on the upper surface. A cavity plate material, a cooling member that penetrates the frame body and has a tip end surface abutting the back surface of the cavity plate material, and a space of the frame body, in which the upper end surface and the lower end surface are the back surface of the cavity plate material and It is characterized by a molten metal forging split mold that is composed of a plurality of supporting members that are in contact with the bottom surface of the frame body and are adjacent to each other.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a mold of the present invention will be described with reference to the drawings by embodiments.

First, as shown in the partially cut-away perspective view of FIG. 1, as a bottomed frame 1, S45C plate material is TIG-welded to have an inner dimension of 330 mm × 330 mm × 200 mm,
A bottomed frame body having a side wall thickness of 40 mm and a bottom portion thickness of 50 mm was prepared.

The thickness of the cavity plate material 2 is:
A 5 mm S20C plate material was tapped and molded following a resin cut into a cavity shape, and a cavity portion having a stepwise shape with a plane dimension of 260 mm × 260 mm, depths of 60 mm and 30 mm was prepared.

The support member 3 has a sectional size of 15 mm × 15.
mm, length: Bundled 476 hard copper bars of 200 mm,
It was manufactured by milling the upper end surface into a shape corresponding to the above cavity shape.

Next, as shown in FIG. 1, the bottomed frame 1
The support member 3 is filled in, the cavity plate member 2 is placed on the support member 3, and the cavity plate member 2 and the bottomed frame 1 are spot-welded,
By fixing, the molten metal forging split mold of the present invention was manufactured.

For the purpose of comparison, a conventional molten metal forging integrated die having the same cavity shape as that of the present invention was manufactured from S45C block material by machining.

Using the mold assembled as described above, the molten metal material: JIS-AC4CH, the molten metal temperature: 780 ° C., the molten metal pressure: 40 t, the cavity surface temperature before the molten metal injection: 400 ° C. Forging was performed, and microcracks were generated on the cavity surface, and the number of shots up to the service life was measured due to this.

The molten metal forging split mold of the present invention is 1300
While the shot reached the service life, the conventional molten metal forging integrated die reached the service life after 500 shots.

In the above-mentioned embodiment, the molten alloy forging of aluminum alloy is described, but the same result is obtained in the molten metal forging of pure aluminum, copper and copper alloy, and further, other die casting method and low pressure casting are used. The same effect is exhibited when it is used for pressure casting such as the method.

[0016]

As described above, the present mold has a small concentration of thermal stress in the mold, and therefore the generation of cracks is suppressed, so that it can be used for a long period of time and brings industrially useful characteristics. Of.

[Brief description of drawings]

FIG. 1 is a partially cutaway sectional perspective view of a molten metal forging split mold of the present invention.

[Explanation of symbols]

 1 Bottomed frame 2 Cavity plate 3 Support member

Claims (1)

[Claims] 1. A bottomed frame body, a cavity plate member provided in a lid shape on the upper end portion of the frame body and forming a cavity for molten metal forging on the upper surface, and an upper end surface and a lower portion in a space of the frame body. A split mold for molten metal forging, comprising: a plurality of support members whose end faces are in contact with the back surface of the cavity plate member and the bottom surface of the frame body and are adjacent to each other.