JPS62101366A - Molten metal forging device - Google Patents

Abstract

PURPOSE:To improve the mechanical properties of a product by providing a space part communicating with the cavity of a molding tool to the molding tool and disposing a moving type piston which retreats when a molten metal solidifies half. CONSTITUTION:The molding tool 1 is constituted of a cope 1A and a drag 1B. The piston 5 which moves back and forth is inserted into the space part 3. An injection sleeve 6 and a plunger 8 which is moved back and forth by a hydraulic cylinder 7 are disposed to the drag 1B. The low melting component grows to the unsolidified region in the central part when the molten metal 10 in the pressurized state in the cavity 2 begins to solidify. The piston 5 is retreated in this stage to form a fissure in the region where the solidification starts. The low melting component is transferred by the high pressure to the space part 3. The macrosegregation of a product part 11 is prevented by the above-mentioned. The mechanical properties of the product are thus improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a molten metal forging apparatus, and more particularly to a molten metal forging apparatus that can prevent segregation of low melting point components from being generated in a product part.

(Prior art) For example, molten metal is introduced into the cavity of a mold consisting of a mold and a lower mold using a plunger and solidified.
For example, the molten metal forging device for producing the product is
It is disclosed in Publication No. 414.

Molten metal forging solidifies the molten metal under a high pressure of 1000 Kg/c+s" or more, so cavities, gas defects, etc. are improved, and high-quality products with excellent mechanical properties can be obtained.

Generally, the molten metal introduced into the mold cavity begins to solidify from the surface layer, that is, the contact surface with the mold, and progresses toward the center until solidification is completed, so local segregation is less likely to occur. .

However, in the case of molten metal forging, since the molten metal is solidified under high pressure, the high pressure acts on the solidification initiation region of the surface layer, and as a result, a large amount of solute components, that is, low melting point components, are removed from the solidification initiation region. The components are discharged into the central unsolidified area. Therefore, macro-segregation occurs in which low-melting point components are concentrated in the final solidification zone of the central portion, and the mechanical properties of the central portion are locally degraded.

+1 [712L-h Or ++ M, Δ Ih
4 'II 'IFL 'R;”-l -h
HI A has low melting point A11j- in the center of the product.
Macro segregation occurs in which Cu-based intermetallic compounds (548°C melting point) crystallize, and when a Cu-Mg-based alloy is molten forged, AJI with a low melting point occurs in the center of the product.
Macro segregation occurs in which a Cu-Mg-based intermetallic compound (melting point: 467°C) crystallizes.

On the other hand, mechanical properties of An-based alloy products are generally improved by heat treatment. For example, JISAC4C, JI
For A-type alloys such as SADCIO, a T6 process consisting of a 480-b quenching process and a 180-b dosing process is performed.

When the above T6 treatment is applied to a humanities alloy product obtained by molten metal forging, the low melting point component of the macro-deflected part melts during quenching heating, and its volume expands, causing water cooling immediately after quenching heating. Sometimes it solidifies and its volume contracts. As a result, there is a problem in that a cavity is created inside the product, and cracks are generated from this cavity toward the outside.

(Object of the Invention) This invention was made to solve the above-mentioned conventional problems, and is a melting/melting solution that can prevent the segregation of low melting point components in the product part. ! The purpose is to provide forging equipment.

(Structure of the Invention) In order to achieve the above object, a molten metal forging apparatus according to the present invention is provided with a space communicating with a cavity of a mold forming a product part, and when injecting molten metal into the cavity, the molten metal forging apparatus according to the invention is provided with a space that communicates with a cavity of a mold forming a product part. When the molten metal is semi-solidified, it retreats and becomes empty +1. It has a configuration in which a movable piston is provided as one part.

Therefore, the low-melting-point component in the center, which is in a molten state, flows into the space communicating with the cavity through the cracks formed in the solidified region (solidified shell) of the surface layer.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a longitudinal cross-sectional view showing an example of a molten metal forging apparatus according to the present invention. In FIG. A communicating space 3 is provided in the upper mold IA.

A piston 5 reciprocated by a cylinder 4 is fitted into the space 3 . Reference numeral 6 denotes an injection sleeve, which is arranged so as to be able to move forward and backward and swing freely relative to the lower mold IB.
A plunger 8 that is reciprocated by a hydraulic cylinder 7 is fitted into the plunger 8 .

In the above configuration, the injection sleeve 6 and the plunger 8 are moved back and tilted as shown by the imaginary line X in FIG.

Next, the injection sleeve 6 and the plunger 8 are returned to the vertical position, and the injection sleeve 6 is advanced and raised to come into contact with the lower surface of the lower mold IH, and then the hydraulic cylinder 7 is activated to raise the plunger 8. , molten metal l in the injection sleeve 6
Inject O into the cavity 2.

Furthermore, it is solidified within the cavity 2 by the plunger 8. As shown in FIG. 2, solidification of the molten metal 10 starts from the surface layer, that is, the contact surface between the upper mold IA and the 'F mold IB, as shown by S, and progresses sequentially toward the center. Due to the high pressure acting on the solidification start zone S during such semi-solidification, multiple solute components, that is, low melting point components, are discharged from the solidification start zone S to the unsolidified zone R in the center.

During the semi-solidification, the cylinder 4 is actuated to move the piston 5 back as shown in FIG. 3, thereby forming a low-pressure space 3 continuous with the solidification start region S. By forming this space 3, the plunger 8 is placed in the solidification start region S corresponding to the space 3.
Cracks occur due to the applied pressure. Since the unsolidified region R consisting of low melting point components has high fluidity, the high pressure applied by the plunger 8 causes the cracks formed in the solidified region S to flow into the space 3 as shown in FIG. Flow into. Therefore, the above-mentioned macro segregation does not occur in the product part 11 that solidifies in the cavity 2, and the molten metal that has flowed into the space 3 is cut after solidifying (effects of the invention). Since segregation of low melting point components is not generated in the product part, a high quality product with excellent mechanical properties can be obtained.

[Brief explanation of drawings]

Fig. 1 is a longitudinal cross-sectional view showing an example of the molten metal forging apparatus according to the present invention, Fig. 2 is a longitudinal cross-sectional view showing the semi-solidified state of the molten metal, and Fig. 3 shows a state in which the piston is retracted to form a space. FIG. 4 is a vertical cross-sectional view showing a state in which a low melting point component has flowed into the space. DESCRIPTION OF SYMBOLS 1...Mold, 2...Cavity, 3...Space, 5...Piston, 8...Plunger, lO...
Molten metal, 11 product departments. sl Figure 2 Figure 3

Claims (1)

[Claims] (1) In a molten metal forging device that solidifies molten metal under pressure with a plunger, a space is provided that communicates with a cavity of a mold forming a product part, and when the molten metal is injected into the cavity, the molten metal is injected into the space. A molten metal forging device characterized by being provided with a movable piston that is inserted into the molten metal and retreats to form a space when the molten metal is semi-solidified.