JPS60231597A - Material of electrode for welding - Google Patents

Abstract

PURPOSE:To obtain titled material excellent in conductivity of electricity and heat and deformation resistance, hard to deposit, high in wear resistance and easy to manufacture by providing an intermediate covering layer of Ni, Co etc. on copper alloy and providing a surface covering layer of dispersion type alloy in which particles of oxide etc. are dispersed on the intermediate covering layer. CONSTITUTION:An intermediate covering layer made of Ni, Co, Cr, Mo or their alloy is provided on copper alloy made by adding metals such as Cr, Zr etc. to copper or dispersing oxides such as Al2O3 etc. and a surface covering layer made of metal or alloy in which particles of oxides, carbides, nitrides or carbonitrides are dispersed in provided on the intermediate covering layer. Thus, material of electrode for welding excellent in conductivity of electricity and heat, small in abnormal heat generation at the time of welding, hard to deposit, durable and high in wear resistance is obtained. Desirable thickness of above- mentioned intermediate covering layer is 0.5-100mu, and the base of Co, Cr, W, Mo or their alloy and carbides of Cr, W, Ti, Ta are desirable.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a welding electrode material, and particularly to a welding electrode material for welding, brazing, etc.

(Background technology) In recent years, highly productive spot welding has come into widespread use, for example, for joining mild steel sheets and galvanized steel sheets in the automobile industry. -Cr alloy, Cu-Cr-Zr alloy, Cu
-Be-Co alloy etc. have been used.

Such welding electrodes require large currents during welding,
Moreover, since it is used continuously, it becomes hot and there is a problem that the tip part is easily cracked, deformed, or worn out.

Therefore, the general characteristics required for welding electrode materials used in spot welding, soma welding, etc., and electric brazing welding are as follows.

■Good electrical and thermal conductivity: As mentioned above, it is necessary to pass a large current through the electrodes, so when there is not much heat generation due to electrical resistance, the generated heat needs to be quickly conducted and cooled. be.

■Deformation resistance: Suboy) In welding, strong compressive stress is applied to the electrode tip during welding, so mechanical strength is required at high temperatures of 500°C or higher and at room temperature.

If the tip of the electrode is deformed or cracked, it is difficult to apply sufficient stress uniformly to the welded part, which adversely affects the welding strength and the appearance of the welded part.

■Do not weld: If the electrode material and the material to be welded, the solder material, etc. are likely to form an alloy, the material to be welded, the solder material, etc. will easily weld to the tip of the electrode, but welding will interfere with welding. , it is desirable that there be no welding.

■ Ease of manufacturing and price: It is desired that the alloy itself be easy to manufacture, have excellent processability into welding electrodes, and be low-priced as a consumable item.

The conventionally used Cu-Cr alloy, Cu-Cr-Zr alloy N Cu-Be-C:o alloy has the following inadequacies in light of the above-mentioned necessary properties. Ta.

In other words, Cu-Cr alloy and Cu-Cr-Zr alloy have high electrical conductivity and are excellent in terms of softening resistance and hardness at high temperatures, but they must be quenched at a high temperature of approximately 1000°C during manufacturing. In addition, these alloys tend to crack at the tip when used as electrodes, and the inventors believe that the cause of this is the presence of Cr. It was found that this was facilitated by

Also, does the C:u-Be-Co alloy have high strength at room temperature?
It has low electrical and thermal conductivity and easily generates heat when used.
Although it did not have excellent softening resistance and was expensive, it was not desirable as an electrode material.

Other materials such as W and No, which have even higher high-temperature strength, can be considered, but other necessary conditions for electrodes, namely high electrical conductivity, may be impaired, and the electrode itself may generate abnormal heat due to resistance, or its toughness may deteriorate. It was difficult to put it into practical use because of cracks and damage caused by the drop.

In addition, a welding electrode having a coating layer of nitride, carbide, or carbonitride on the surface of a copper alloy in which oxides are dispersed (JP-A-58-1
No. 41878) has been proposed, but because the electrical conductivity of the surface layer is low and the heat generation at the tip is large, the copper alloy that is the base material is likely to soften, deform, and melt, and the service life is insufficient. Ta.

(Disclosure of the Invention) The present invention has been made to solve the above-mentioned problems, and has excellent electrical and thermal conductivity, and when used as a welding electrode,
It is an object of the present invention to provide an electrode feed for welding that has less excess heat generation at the tip of the electrode, less wear on the electrode, good adhesion of the surface coating layer, and is easy to manufacture.

The present invention provides Ni, Go+Cr, M on a copper alloy.
an intermediate coating layer made of o or an alloy thereof, and a surface coating layer made of a metal or alloy (hereinafter referred to as a dispersed alloy) in which oxides, carbides, nitrides, or carbonitrides are dispersed. This is a welding electrode material characterized by the following.

In the present invention, the copper alloy that serves as the base material is an alloy based on copper and to which metals such as Cr+ Zr, Be, and CotMo are added (e.g., Cu-Cr+ Cu-Cr-Z).
rtCu-Be-Co, Cu-Zr-Fe-P alloy, etc.), and dispersion-strengthened copper alloys in which oxides such as A9203 are dispersed.

In addition, the dispersed alloy constituting the surface coating layer is a metal or an alloy,
For example, it is based on Co+Cr, W, Mo+Co+Ni, etc. or alloys thereof (e.g., Ni-Cr alloy, etc.), and contains oxides, carbides, nitrides, carbonitrides, etc.
For example, chromium carbide, tungsten carbide, titanium carbide, silicon carbide, aluminum oxide, titanium nitride.

It is made by dispersing particles of tantalum nitride, titanium carbonitride, etc.

This surface coating layer is formed by dispersing oxide, carbide, nitride, or carbonitride particles that remain on the surface even when the base metal or alloy of the dispersion type alloy is used for welding or soldering. In order to accumulate well, the coating thickness should be 5 to 1.
00μ is preferable. If it is less than 5μ, there will be little welding prevention effect.
If it exceeds 100μ, the industrial cost will be high and the electrode tip will generate a lot of heat.

In addition, the intermediate coating layer has the primary purpose of improving the adhesion between the copper alloy base material and the surface coating layer, and preventing S++ separation due to thermal stress.
The purpose of The thickness of this coating is preferably 0.5 to 100μ, and if it is less than 0.5μ, the adhesion property - 1 - effect is small, and 10
If it exceeds 0μ, industrial costs will increase.

Note that due to the adhesion between the copper alloy of the copper alloy and the intermediate coating layer, a base layer of Cu, Ni, etc. may be provided.

Hereinafter, the present invention will be explained by examples using the drawings.
1 to 5 are longitudinal cross-sectional views showing electrode tips according to embodiments of the present invention. In the figure, 1 is a copper alloy constituting the chip body, '3 is the tip of the electrode, and 1' shown in Figure 4 is the chip body, with a copper alloy 2 (e.g.,
Carbon fiber reinforced copper alloy, etc.) are bonded.

4 is an intermediate coating layer made of Ni+Co+Cr+Mo or an alloy thereof, and 5 is a surface coating layer made of a dispersed alloy as described in []11.

In FIG. 1, the tip 3 of the copper alloy 1 is coated with an intermediate coating layer 4 and a surface coating layer 5.

In FIG. 2, the entire surface of the copper alloy 1 is coated with an intermediate coating layer 4 and a surface coating layer 5.

In FIG. 3, the entire surface of the copper alloy 1 is coated with a copper coating layer 6 by electroplating, and the surface of the tip 3 is coated with an intermediate coating layer 4 and a surface coating layer 5.

In FIG. 4, the surface of the copper alloy 2 at the center of the chip 1' is coated with an intermediate coating layer 4 and a surface coating layer 5.

The tip shown in FIG. 5 is a tip for spot welding, in which the tip 3 of a copper alloy 1 is coated with an intermediate coating layer 4 and a surface coating layer 5.

To coat the dispersion alloy of the surface coating layer, electroplating,
Methods such as electroless plating and steaming method are used. For example, N
i. Electroplating is performed by dispersing particles of a dispersed compound in a plating solution such as Co or Cr.

(Example) A welding electrode tip body as shown in FIG. 1 was made from the base metal alloy shown in Table 1, and an intermediate coating layer 4 and a surface coating were applied to the − of the tip 3 as shown in Table 1. Layer 5 was coated under various conditions. The covering power methods used were electroplating (A), Spanocri/G (B), ionoblating (C) and activated reactive vapor deposition (l).

The dimensions of the electrode are: diameter 16 at the parallel part, target diameter 8+ at the tip.
There was lll1.

The obtained electrode depth was used for spot welding, and the thickness was 0.
Two 8 mm galvanized iron plates were stacked on top of each other and used as electrodes at a current of 10 kA, a pressure of 200 kg, and a welding time of 2.
Spot welding was carried out under the conditions of 5 cycles, and the number of welds until welding occurred on the electrode was measured. The results are shown in Table 1.

Table 1 From Table 1, it can be seen that N11 to 6 according to the present invention have a significantly longer lifespan until welding occurs and do not cause peeling, compared to the comparative example and the conventional example. Comparative Examples Nos. 7 and 8 caused peeling.

(Effects of the Invention) The welding electrode material of the present invention, which is configured in two series, has the following effects.

(a) Since the electrode body is made of copper alloy, it has excellent electrical and thermal conductivity, and there is little abnormal heat generation during welding or soldering.

(b) Since a surface coating layer made of a metal or alloy in which oxides, carbides, nitrides, or carbonitrides are dispersed is provided on the outermost surface, the metal or alloy in the dispersed alloy disappears during welding or soldering. However, the dispersion compound particles remain and accumulate on the surface with good adhesion, and since the dispersion type alloy has good oxidation resistance, welding is difficult and the service life is shortened. Especially Zn+Sn+half [b,
It is also difficult to weld to welded materials coated with low melting point metals such as Ag or alloys.

Also, since it is a dispersed alloy, there is less wear.

(c) NL Co, Cr, Mo in -4- of the copper alloy
Alternatively, since an intermediate coating layer made of an alloy thereof is provided, the adhesion between the copper alloy and the surface coating layer is good and no separation occurs.

(d) All of the coating layers are thin and are mainly made of metal or alloy, so there is no excess heat generation at the tip of the electrode.

(E) (1111 structure or medium line), and the surface coating layer can be easily produced by electroplating using a plating solution in which dispersed compound particles are dispersed, so it is easy to produce.

[Brief explanation of the drawing]

FIGS. 1 to 5 are longitudinal cross-sectional views showing electrode tips according to embodiments of the present invention. 1.2...Copper alloy, 1'...Chip body, 3...
Tip, 4.4'... Intermediate coating layer, 5... Surface coating layer, 6... Copper coating layer. Spiritual I map, Government 2, Jifang 3, Ren 4

Claims (4)

[Claims] (1) Copper alloy” Second, N! + Co + Cr +
An intermediate coating layer made of Mo or an alloy thereof, and a surface coating layer made of a metal or alloy (hereinafter referred to as a dispersed alloy) in which oxide, carbide, nitride, or carbonitride particles are dispersed. A welding electrode material characterized by being provided with. (2) The welding electrode material according to claim 1, wherein the intermediate coating layer has a thickness of 0.5 to 100 μm, and the surface coating layer has a thickness of 5 to 100 μm. (3) The welding electrode material according to claim 1 or 2, wherein the dispersed alloy is based on C01Cr+w, Mo, or an alloy thereof. (4) The welding electrode material according to claim 1, 2, or 3, which is a carbide or a carbide of Cr+W+Tl or Ta.