JPS61176494A - Coating material for welding - Google Patents

Abstract

PURPOSE:To improve melt-sticking resisting properties to a stock to be welded and the thermal-fatigue resisting properties, by forming the coated layer of carbonate, nitrate, carboboride, nitride-boride, and mutual solid solutions of them of the metals of 4a, 5a, 6a groups in the table of periodic law, on the surface of Cu or Cu alloy. CONSTITUTION:A pure copper or a copper alloy containing Cd, Ag, Ni, Cr, Be, etc. is used for the substrate of a coating material. Among the compounds of 4a, 5a, 6a groups of a coated layer, the material of nitrate of titanium and tantalum containing by molar percent, 70-99.5% N, 0.5-30% O, 98.5-99.9% Ti, 0.1-1.5% Ta, is most desirable in its properties, and the thickness of coated layer of 0.5-3mum is suitable. The coated layer is formed by chemical or mechanical vapor deposition method. In this way, an electrode member for welding excellent in the melt-sticking resisting properties to a stock to be welded and the thermal fatigue resisting properties, is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a welding coating material suitable for welding electrodes for spot welding, seam welding, etc., or welding nozzles for gas arc welding, plasma welding, etc.

(Conventional technology) Conventional electric resistance welding, spot welding among welding methods.

When welding the welded material by placing the material between the electrodes and supplying current while applying pressure using electrodes such as seam welding, the welding part needs to be raised to the welding temperature. It is desirable that the temperature does not rise in the contact area of the part to be welded. For this reason, the electrode material is silver or copper, which has high electrical and thermal conductivity, and cadmium is a material that has high strength at room temperature or high temperature. Copper-based materials, chromium copper-based materials.

Beryllium copper-based materials and tungsten copper-based materials are used. In addition, electrodes made of these copper alloy materials are classified into copper or copper alloys according to Periodic Table 4a because the electrode and the material to be welded adhere to each other at the contact point between the electrode and the material to be welded, significantly shortening the life of the electrode. , 5a, 6a group metal carbides, nitrides, or carbonitride coating layers have been proposed.

(Problems to be Solved by the Invention) Electrodes made of copper or copper metal can be made by welding commonly used steel materials, steel materials plated with Zn or Sn, or electrical components such as aluminum alloys and copper alloys as materials to be welded. In this case, the problem is that the welded material spreads to the electrode surface, or the welded material is welded to the electrode surface, or the electrode surface that comes into contact with the welded material is plastically deformed, resulting in the end of its life in a short period of time. There is. In addition, copper or copper alloys are added to periodic table 4.
Electrodes formed with a coating layer of carbide, nitride, or carbonitride of Group A, 5A, and 6A metals have a longer lifespan because the coating layer is more effective in preventing the material to be welded from diffusing to the electrode surface. However, if the electrode is used continuously, the coating layer will be destroyed due to thermal fatigue on the electrode surface, and the welding of the welded material will be severe, resulting in a problem that the life of the electrode will be shortened.

The present invention solves the above-mentioned conventional problems. Specifically, the present invention improves the effect on thermal fatigue without reducing electrical conductivity and thermal conductivity as much as possible, and prevents welding with metals or alloys. The object of the present invention is to provide a coating material for welding that has the following properties.

(Means for Solving the Invention) The present inventors have developed a material suitable for welding, which suppresses the decrease in electrical conductivity and thermal conductivity as much as possible, increases the material strength, and also prevents the decrease in hardness and yield point at high temperatures. The present invention was completed by pursuing a material that has excellent welding resistance with materials to be welded.

In other words, the welding coating material of the present invention has a surface of a substrate made of copper or a copper alloy that is coated with 4a of the periodic table.

Carbonates, nitoxides, carborides of group 5a and 6a metals,
Judging from the electrical conductivity and thermal conductivity, the substrate used in the present invention has a coating layer formed of a single layer or a multilayer of two or more of nitride borides and their mutual solid solutions. Pure copper is best, judging from tensile strength, yield point, and hardness, Cd, Ag, Ni, Cr, Be, Si
, Co.

Te, P, W, or a copper alloy containing a trace amount of oxygen may be used. Also, these copper or copper alloys may be plated with an oxide film or a metal 9 alloy or metal compound using physical vapor deposition (PVD).
, chemical vapor deposition (CVI)) may be used as the substrate.The coating layer formed on the surface of these substrates may be made of carbonates of metals from groups 4a, 5a, and 6a of the periodic table, such as Ti ( C, O), Zr (C, O).

Hf (C, 0), V (C, O).

Nb (C, O), Ta (C, O).

Cr (C, O), Mo (C, O).

W (C, O), nitride, e.g. Ti (N, O), Zr (N, O).

Hf (N, O), V (N, 0).

Nb (N, O), Ta (N, O).

Cr (N, O), Mo (N, O).

W(N,O), carborides, e.g. T i (C, B), Z r (C, B).

Hf (C, B), V (C, B).

Nb (C, B), Ta (C, B).

Cr (C, B), Mo (C, B).

W(C,B), nitride boride, e.g. Ti (N, B), Zr (N, B).

Hf (N, B), V (N, B).

Nb (N, B), Ta (N, B).

Cr (N, B), Mo (N, B).

W (N, B) and their mutual solid solution 1 e.g. T
i (C, N, O), T i (C, N,
O, B).

(Ti, Ta) (C, 0).

(Ti, Ta) (N, O).

(Ti, Ta, W) (C, O).

(Ti, Ta, W) (N, O), etc., and these coating layers may have a stoichiometric or non-stoichiometric composition, and the coating layer contains oxygen and/or boron. It is necessary. Among these coating layers, the coating layer is preferably made of nitride oxides of titanium and tantalum, especially from the viewpoint of thermal fatigue resistance of the coating layer and adhesion resistance between the coating layer and the material to be welded. The metal elements are 70 mol% to 99.5 mol% nitrogen, 0.5 mol% to 30 mol% Mj elements (Ti
, Ta) (No r No 995, Oo 0
05-030) is preferable, and in this coating layer made of titanium and tantalum nitride oxide, the metal element is titanium in an amount of 98.5 mol % to 99.9 mol %.

Tantalum is 0.1 mol% to 1.5 mol% (T
i o, qas No, qqq,
T ao oo + N o ops
) (N, O) The thickness of the fjI layer in the welding coating material of the present invention, which preferably has a composition of From the viewpoint of fatigue resistance, welding resistance, and peeling resistance, 0.5 lm to 3 gm is preferable.

The method for producing the welding coating material of the present invention involves grinding, polishing, or lapping the surface of a base made of copper or copper alloy as necessary, and then cleaning with ice, a neutral detergent, an organic solvent, etc. Alternatively, steam cleaning, sonic cleaning, or surface etching may be performed as necessary, and then the substrate may be placed in a reaction vessel and manufactured by a chemical vapor deposition method or a physical vapor deposition method. When produced by chemical vapor deposition, halides of titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum or tungsten, such as TiCl1n, TaCMs
, wClb, etc. and CHa, N
H4, H2, N2.

C2H2, N20. The coating layer can be formed in a gas selected from H20, CO2, C0,02, etc. Generally, when forming a coating layer by chemical vapor deposition, it is necessary to process at a relatively high temperature, but since it is necessary to take into account thermal deformation of the substrate, it is desirable to keep the temperature at about 700°C to 900°C. Due to the problem of thermal deformation, it is preferable to use a physical vapor deposition method that can be processed at a lower temperature than a chemical vapor deposition method.When forming a coating layer by a physical vapor deposition method,
It can be produced by sputtering, ion blasting, or plasma chemical vapor deposition.For example, a metal alloy or mixture containing the metal elements of the desired coating layer is evaporated and ionized in a reaction vessel in which a glow discharge is generated. After that, inert gas, H2, N2 is added to this reaction vessel.
, N Ha.

C2H2, N20. CH4, H20, CO2.

A coating layer can be formed on the surface of the substrate by introducing a gas such as CO or 02 and maintaining the temperature at 100°C to 650°C.

(Function) The welding coating material of the present invention has a trace amount of oxygen and/or
Or, by containing boron, it becomes a coating material with excellent welding resistance, and a minute amount of oxygen and/or boron in the coating layer makes the crystal grains of the coating layer fine, forming a dense coating layer. It is made of a coated material. Also,
In particular, when the coating layer is made of nitride oxides of group 4a metals and group 5a metals of the periodic table, it has excellent thermal fatigue resistance.

(Example) Example 1 A base made of a Cu alloy (Cu-Cr-Zr) spot welding gap (16φ x 23 layers, tip diameter 6φ) was installed in the reaction vessel of an ion blating device. Then, the inside of this reaction vessel was evacuated, the temperature was raised to 500°C, and Ar bombardment was performed at 15 Torr for 10 minutes.
Next, a Ti ingot containing 4% by weight of Ta as an evaporation material was evaporated and ionized under the conditions of 6kV and 0.4A using E]3'f, and a 9.5X10-' mixed gas of N2-5% by volume of O2 was used as a reaction gas. Introduce up to Torr and apply 1 to the base.
By applying a negative bias voltage of 00 V and adjusting the deposition time, products No. 1 to No. 6 of the present invention as shown in Table 1 were obtained.
Comparative product No. 1 is a substrate similar to that used in the invention product No. 1-No.
A comparative amount of NO2 was obtained by forming a coating layer on the surface of the same substrate as No. 6 using a Ti ingot as the evaporation material and using N2 gas in the same manner as in Example 1.

Table 1 shows the results of observing the coating layers of these invention products 11 &) 1 to No. 6 and comparative amount No. 2 using an ion microanalyzer and an electron microscope.

The invention product Not-No. 6 and comparative quantities Not-No. 2 were each attached to a spot welding machine to form a Zn with a thickness of 0.801 m.
nPig iron plate 45g/m? ) spot welding was performed. The results are also listed in Table 1.

Margin Example 2 Using a carbon dioxide arc welding electrode (contact tip) made of a precipitation-hardening copper alloy (Cr-Cu) as a base, the surface of this base was coated with the same ion blating method as in Example 1 (T io 995, Tao, oos ) (
NO, 9+2.

A suspension 7 of the present invention was obtained, which was coated with 2.5 gm of a coating layer having a composition of (Oo, osa). A carbon dioxide gas arc welding electrode consisting only of a precipitation hardening copper alloy without forming a coating layer was used with a comparative amount of Nb3 and Ti on the surface of the precipitation hardening copper alloy.
Comparative amount No. 4 was obtained by forming a coating layer of 2.5 gm of C.

This invention product No. 7 and comparative amount No. 3. No. 4 was used for each 2.0 mm thick steel plate at a current of 150 A.

CO2 gas fit20JL/sin, speed 500am
/min. As a result of carbon dioxide welding, the comparative amount No. 3
In 1.5 hours, the weld deposits were deposited on the electrode tip and the outer circumferential surface due to sputtering during welding, and the life was reached, and the comparative amount No.
Inventive product No. 4 had a similar lifespan of 3.0 hours, while product No. 7 of the present invention could be used for as long as 5 hours.

(Effects of the Invention) The welding coating material of the present invention has excellent adhesion resistance with the welded material and also has excellent thermal fatigue resistance, so it can be used for resistance welding such as spot welding and seam welding. Welding electrodes or resistance brazing can be effective as welding electrodes. It also has excellent adhesion resistance with deposits sputtered at high temperatures, so it can be used as a welding nozzle for gas arc welding, plasma welding, etc., or as a contact tip for inserting welding rods or welding wires for gas arc welding or plasma welding. It is also an industrially useful coating material that can exhibit effects.

Claims (3)

[Claims] (1) Periodic table 4a on the surface of a substrate made of copper or copper alloy
, Formation of a coating layer consisting of a single layer or a multilayer of two or more of carbonates, nitrides, carborides, nitrides, and mutual solid solutions of group 5a and 6a metals. Characteristic coating material for welding. (2) The above-mentioned coating layer is made of nitride oxide of titanium and tantalum, and the nonmetallic element in the nitride oxide is 70 mol% to 99% nitrogen.
．． The welding coating material according to claim 1, characterized in that the content is 5 mol% and oxygen is 0.5 mol% to 30 mol%. (3) The above-mentioned coating layer is made of nitride oxide of titanium and tantalum, and the metal element in the nitride oxide is 98.5 mol% to 98.5 mol% of titanium.
99.9 mol%, tantalum 0.1 mol% to 1.5 mol%
Claims 1 and 2 are characterized in that:
Coating material for welding as described in section.