JPH0716762A - Surface hardening method of al material or its alloy material - Google Patents

Abstract

PURPOSE:To provide the surface hardening method of Al material or Al alloy meterial capable of forming the hardened layer having excellent abrasive wear resistance, adhesive wear resistance and plastic deformation resistance. CONSTITUTION:Al material 1 for its surface to be hardened is shown and groove 2 is arranged on the surface to be hardened of Al material 1. A cladding metal 3 is filled in the groove 2, the cladding metal, which is a copper tube 4 filled with WC-17vol% Co5 as adbesive resistance material and then rolled to a plate, is used. The materials are charged in an electron beam welding machine and the cladding metal part 3 is irradiated with electron beam. The cladding metal part 3 is headed and melted by electron beam irradiation, as a result, the cladding alloy uniformly dispersed with adhesive resistance material in the matrix alloy, in which the intermetallic compound consisting of a copper of the tube 4 and Al and Al exist, is formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aluminum material or an alloy material thereof which is capable of producing an aluminum material or an alloy material thereof having excellent abrasive wear resistance, adhesion wear resistance and plastic deformation resistance. The present invention relates to a surface hardening method.

[0002]

2. Description of the Related Art Aluminum and its alloys have the excellent property of being lightweight and are widely used in various equipment and structures, but they are harder than other metals and alloys. And wear resistance is poor. Therefore, when it is used for sliding parts that require wear resistance, it has been conventionally used for ion implantation, surface hardening, hard plating, ion nitriding,
Techniques such as diffusion infiltration heat treatment, thermal spray, arc,
The surface of an aluminum material or its alloy material is hardened by a technique such as overlaying by welding using an electron beam or a laser beam, and the defects of hardness and wear resistance of these materials are compensated.

[0003]

However, arc and laser beam welding have a drawback that defects such as porosity are likely to occur frequently in hardfacing alloys. On the other hand, the formation of the hardfacing alloy by electron beam welding has an advantage that defects such as porosity hardly occur because the electron beam welding is performed in a high vacuum. Further, the electron beam welding has an advantage that even if a welding crack occurs, the portion can be repaired by remelting by the electron beam.

For this reason, many methods have been put into practical use in which a metal such as copper is overlay welded to an aluminum material or its alloy material by an electron beam to form a hardfacing alloy layer on the aluminum material or its alloy material. . However, the build-up alloys of metals such as copper are superior to abrasive wear (wear due to cutting or overcutting),
It has a disadvantage that it is inferior to cohesive wear (wear caused by adhesion and destruction of local contact points).

In order to improve the anti-adhesion resistance, it is considered that an anti-adhesion material such as ceramic powder is added to the build-up alloy and dispersed in the aluminum material or its alloy material. In the method for strengthening an aluminum part disclosed in Japanese Patent Laid-Open No. 4-135068, the strengthened part of the aluminum part is formed into a concave shape, and the mixed powder is supplied with the ratio of the ceramic powder and the heat-resistant metal powder being approximately 1: 1. At the same time, it is built up by high-density energy welding.
However, when electron beam welding is used as the method of high-density energy welding in this method, there arises a problem that powder is scattered and welding becomes impossible.

The present invention has been made in view of the above points, and is an aluminum material capable of forming a hardened layer having excellent abrasive wear resistance, adhesion wear resistance and plastic deformation resistance, or It is an object to provide a surface hardening method for an aluminum alloy material.

[0007]

According to the surface hardening method of an aluminum material or its alloy material according to the present invention, a ceramic material or a mixed material of a ceramic material and a metal is internally provided on the surface of the aluminum material or its alloy material. A feature is that a metal pipe is provided, and the metal pipe portion is irradiated with an electron beam to form a thick film hardfacing alloy layer on the aluminum material or its alloy material.

[0008]

According to the method of hardening the surface of an aluminum material or its alloy material according to the present invention, a metal pipe having a ceramic material or a mixture of a ceramic material and a metal therein is provided on the surface of the aluminum material or its alloy material. Irradiating the metal pipe part with an electron beam to form a thick film hardfacing alloy layer on the aluminum material or its alloy material,
The surface of the aluminum material or its alloy material is hardened.

Since the overlay material of the metal pipe filled with the adhesion resistant material powder such as ceramic powder is rolled into a plate shape, the adhesion resistant material powder is wrapped in metal and solidified. The metal pipe is made of aluminum or a metal that is compatible with its alloy material, and the plate-shaped build-up material is inserted into the groove cut on the surface of the aluminum alloy material and electron beam welded. Familiarity between the metal and the adhesion-resistant material powder becomes good, scattering of the adhesion-resistant material powder is small, and the adhesion-resistant material powder is dispersed almost uniformly in the molten metal.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows an aluminum (Al) material 1 whose surface is to be hardened, and a groove 2 having a depth of 1 mm and a width of 4 mm is provided on the surface of the aluminum material 1 to be hardened.
The groove 2 is filled with a build-up material 3. As the build-up material 3, a copper (Cu) pipe 4 having an outer diameter of 3 mm and an inner diameter of 2 mm is used as an anti-adhesive material WC-17. Vol% Co (ceramic material containing cobalt in tungsten carbide) 5 was filled and rolled into a plate shape having a cross section of 1 mm × 4 mm.

Although not shown, the material shown in FIG. 1 is put into an electron beam welding machine, and an electron beam is irradiated onto the overlay material 3 portion of the aluminum material 1. The irradiation of the electron beam is performed along the overlay material 3, the part of the overlay material 3 is heated by the irradiation of the electron beam, and the overlay material 3 is melted and dispersed inside the aluminum material 1. That is, a build-up alloy in which the adhesion-resistant material is uniformly dispersed in the matrix alloy containing the intermetallic compound of copper and aluminum, which is the material of the pipe 4, and aluminum is formed.

The hardfacing material used in the above method has a compounding ratio of 75 vol% Cu and 25 vol% WC-17% Co. The appearance of this hardfacing alloy was observed, but the bead appearance was good, and no defects were observed even after the dye penetrant flaw detection test. The structure was observed with a microscope. WC was almost uniformly dispersed in the overlay alloy, and the structure of the matrix metal was mainly α (Al) and α (Al) and θ (CuA
It was a eutectic of l ₂ ).

Although WC-17% Co is used as the ceramic material in the above-mentioned embodiments, other ceramic materials may be used. For example, titanium carbide (TiC) powder was filled in a copper pipe and electron beam welding was performed, and similarly good results were obtained. FIG. 2 shows an evaluation result when a surface hardening experiment of an aluminum material was performed by using electron beam welding and using a built-up material in which various ceramic materials were filled in a copper pipe.

Along with this experiment, a method of overlaying a surface of an aluminum alloy by spraying a metal powder such as copper or nickel and a powder of an adhesion resistant material such as a ceramics powder as an overlay material by electron beam welding is used. I experimented. Compared with the method using a metal pipe, this thermal spray coating has more scattering of the overlay material, the bead appearance is not good, and the dispersion of the anti-adhesion material is non-uniform and the amount of dispersion is small. Depth is 2
In some cases, it was less than mm, which was clearly inferior to the case of performing electron beam welding using a metal pipe.

FIG. 3 shows an aluminum base material (JIS A5
No. 052), the results of the Ogoshi-type rapid wear test when various build-up materials are used are shown. In the figure, the dotted line A shows the case where only the aluminum base material is used, and the dotted line B shows the case where only Cu is used as the overlay material. When the solid line C is Cu + 25 vol% (WC-17% Co) as the overlay material, the solid line D is Cu + 48 vol% (WC) as the overlay material.
-17% Co), the one-dot chain line E indicates the case of using Cu + 52 vol% TiC as the overlay material.

The horizontal axis of FIG. 3 is the friction velocity, and the vertical axis is the specific wear amount. Further, the above-mentioned wear test was carried out using SUJ2 (Vickers hardness HV650) as a rotating disk under the condition of constant surface pressure (final load 2.1 Kgf) and the friction distance of 600 m. The conditions for electron beam welding of the overlay material were an acceleration voltage of 40 KV and a beam current of 70 mA.

As is clear from FIG. 3, in the case of using the overlay material in which the ceramic material was filled in the copper pipe, the specific wear amount was smaller than that of the aluminum base material under any wear condition, and it was excellent. Shows wear resistance. Also,
Compared with the overlay alloy made of only copper, the specific wear amount is small and the wear resistance is excellent when the friction speed is low.

Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments and various modifications can be made. For example, although aluminum is used as the base material, the present invention can be applied to the case where an aluminum alloy material is used as the base material. Further, the present invention can be applied not only to a flat base material but also to a cylindrical base material. In that case, a groove may be provided around the cylindrical base material, and a ring-shaped build-up material may be embedded in the groove. Furthermore, although copper is used as the material of the metal pipe, other metals may be used, and
An aluminum pipe may be used.

[0019]

As described above in detail, according to the present invention, a metal pipe having a ceramic material or a mixture of a ceramic material and a metal therein is provided on the surface of an aluminum material or its alloy material, and the metal pipe portion is provided. Since a thick film hardfacing alloy layer was formed on an aluminum material or its alloy material by irradiation with an electron beam, a hardened layer having excellent abrasive wear resistance, adhesion wear resistance and plastic deformation resistance is formed. be able to.

[Brief description of drawings]

FIG. 1 is a view showing a cross section of an aluminum base material and an overlay material according to an embodiment of the present invention.

FIG. 2 is a diagram showing an evaluation result of a surface hardening experiment of an aluminum material.

FIG. 3 is a diagram showing the results of an Ogoshi-type rapid wear test when various overlay materials are used.

[Explanation of symbols]

 1 Aluminum base material 2 Groove 3 Overlay material 4 Copper pipe 5 Ceramics material

Claims (1)

[Claims] A metal pipe with a ceramic material or a mixture of ceramic material and metal inside is provided on the surface of an aluminum material or its alloy material, and the metal pipe portion is irradiated with an electron beam to cure the aluminum or its alloy material in a thick film. A surface hardening method for an aluminum material or an alloy material thereof so as to form a hardfacing alloy layer.