JP3554058B2 - Aluminum extrusion parts and method of manufacturing the same - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a part used in aluminum extrusion in aluminum sash manufacturing and the like, for example, a part having improved aluminum adhesion resistance to a stem, a dummy block or an attached dummy which comes into contact with an aluminum billet and serves to extrude the same. And a method of manufacturing the same.
[0002]
[Prior art]
Conventionally, tool steel such as SKD61 has been used as a component used for aluminum extrusion. This is because the aluminum billet is heated to a temperature of 400 to 500 ° C. at the time of extruding aluminum, so that the strength at such a temperature is required for an extruded part.
[0003]
By the way, in the aluminum extrusion, the extrusion parts come into contact with the high-temperature aluminum billet, so that the aluminum adheres to the extrusion parts during operation. Then, due to the adhesion of the aluminum, the operating rate may be reduced, or extrusion may be difficult. Therefore, at present, extrusion is performed while applying a release agent to the end face of the extruded part or the aluminum billet.
[0004]
[Problems to be solved by the invention]
However, such a method of applying a release agent requires time for the application, which is a problem when the extrusion time is to be shortened even a little and the operation rate is improved.
In some cases, the release agent is applied manually, which raises concerns about safety issues and causes the release agent to be scattered around the extruder, contributing to contamination. In terms of hygiene, it is desired to avoid using a release agent. In addition, there are costs associated with using release agents.
[0005]
SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art and to provide an extrusion part to which aluminum does not adhere and a method of manufacturing the same.
[0006]
The object of the present invention is attained by employing the following means. That is, in a component for extruding aluminum, a coating of a cermet material having excellent aluminum adhesion resistance is formed on the surface thereof by a discharge coating method .
[0007]
In general, as a method of forming a coating on the surface of a component, overlay welding, thermal spraying, plating, or the like is used. In aluminum extrusion components, tool steel such as SKD61 is used. In the method according to the above method, high-temperature preheating is required in order to prevent hardening cracks in the weld heat-affected zone, and welding may be difficult. Further, in the method using thermal spraying or plating, the adhesion strength between the component and the coating film is insufficient, and peeling occurs. Further, in the overlay welding or thermal spraying, there is also a problem that heat is applied to the component to cause distortion, and it is difficult to obtain predetermined accuracy. On the other hand, by using the discharge coating method, the heat effect on the component can be suppressed only to the surface layer portion, and the component can be coated without causing hardening cracks and distortion of the heat affected zone. is there. In addition, in the discharge coating method, only the surface layer of the component is melted, and the coating is welded and the coating and the component can be diffused. The adhesion strength between the component and the coating is higher than that of thermal spraying or plating. ,Are better.
[0008]
On the other hand, as a result of studying a film having excellent aluminum adhesion resistance, it was found that the cermet material was excellent. That is, by using a cermet material in which ceramic fine particles are dispersed and present in a metal matrix, aluminum adhesion resistance can be improved, and at the same time, high-temperature strength and abrasion resistance required for aluminum extrusion parts are also added. It became possible to grant. Furthermore, by using a cermet material in which borides such as titanium boride and molybdenum boride are dispersed in a metal matrix as a cermet material, aluminum adhesion resistance, high-temperature strength, wear resistance and oxidation resistance are further improved. Was completed.
[0009]
By the way, as a method of applying such a cermet material to a part for extruding aluminum, there are a method of manufacturing the part itself with the cermet material, and a method of lining the cermet material on the surface of the part made of tool steel or the like. However, the cermet material is expensive and the workability is not good, so that it is difficult to manufacture the part itself from the cermet material, and even if it is possible, it requires a great deal of cost. I do. Furthermore, components made of only cermet material have poor toughness and may be chipped, cracked or broken.
[0010]
Therefore, when applying a cermet material to a part for extrusion, a method of lining the surface of the part is good. Then, as a method of lining the cermet material, build-up welding can be considered, but in this case, the cermet material is melted by the heat of the welding arc and the surface of the component is lined, so that a crack occurs in the cermet material coating, A sound coating cannot be obtained. A method using thermal spraying is also conceivable, but the adhesion strength between the component and the coating is insufficient, which causes peeling during use.
[0011]
Compared to these methods, the discharge coating method is a method in which high-frequency discharge is repeatedly applied between a cermet material to be an electrode and a component, and the cermet material is applied to the surface of the component in a state of semi-molten fine particles. Because of the coating, a sound coating is obtained without occurrence of cracks or the like. Furthermore, since the surface layer of the component is melted to the minimum necessary range by the discharge, the adhesion strength between the component and the coating is excellent.
Therefore, as a method for providing a film having excellent aluminum adhesion resistance to a component for extruding aluminum, a cermet material is preferably coated by a discharge coating method.
Further, the fact that the material of the aluminum extrusion component is tool steel is also suitable for the discharge coating method, as described above.
[0012]
【Example】
Hereinafter, examples of the present invention will be described.
FIG. 1 shows a hot extrusion mechanism of aluminum. An aluminum billet 1 is inserted into a container 2, pressure is applied between a stem 3 and a die 4, and an aluminum product having a constant cross-sectional shape is extruded from a die hole provided in the die. In some cases, a dummy block 5 is attached to the tip of a stem for extruding an aluminum billet. This is because when damage such as deformation occurs due to high stress generated during extrusion, only the dummy block needs to be replaced without replacing the entire stem.
[0013]
This embodiment is applied to this dummy block. That is, in three types of dummy blocks having an outer diameter of 7 inches, 10 inches, and 12 inches, the entire surface in contact with the aluminum billet, and the outer peripheral surface in contact with the container, within a range of 20 mm from the surface in contact with the billet, Discharge coating was performed. The coating layer was a cermet material of 75% by weight of MoB + 25% by weight of Ni and had a thickness of 30 μm.
[0014]
When the aluminum alloy was extruded using the dummy block subjected to such a discharge coating treatment, it became possible to reduce the number of times the release agent was applied to the end face of the aluminum alloy billet to 1/10. In other words, conventionally, it was necessary to apply a release agent to each aluminum alloy billet. However, by applying the present invention, if the application is performed once every ten billets, the adhesion of the aluminum alloy occurs. Not confirmed. Furthermore, there is a small gap between the outer periphery of the dummy block and the inner surface of the container in order to slide the dummy block in the container. A release agent must also be applied to the outer peripheral surface. In the past, the number of times was increased for each aluminum alloy billet. However, by applying the present invention, it has become possible to reduce the number of billets to 1/10, that is, 1/10.
[0015]
【The invention's effect】
As described above, according to the present invention, it is possible to prevent aluminum from adhering to an aluminum extruded part, so that an efficient extruding operation can be performed.
Further, the number of times of application of the release agent can be greatly reduced, the deterioration of the working environment due to the scattering of the release agent can be prevented, the use amount of the release agent has been reduced, and the cost has been improved.
[Brief description of the drawings]
FIG. 1 is a diagram of a mechanism for hot extrusion of aluminum.
[Explanation of symbols]
1 Aluminum billet 2 Container 3 Stem 4 Dice 5 Dummy block

Claims (4)

A component for extruding aluminum, characterized in that a coating of a cermet material having excellent aluminum adhesion resistance is formed on the surface thereof by a discharge coating method. The aluminum extrusion component according to claim 1, wherein the cermet material is a cermet material in which boride is dispersed in a metal matrix . A method for manufacturing an aluminum extrusion component, comprising forming a coating of a cermet material having excellent aluminum adhesion resistance on a surface of the aluminum extrusion component by a discharge coating method. The method for manufacturing a component for extruding aluminum according to claim 3, wherein the cermet material is a cermet material in which boride is dispersed in a metal matrix .

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