JPS59133991A - Film for preventing sticking of welding spatter - Google Patents

Abstract

PURPOSE:To provide a titled film having excellent resistance to stripping from a ferrous material by consisting the same of the three layers; an underlying melt-sprayed film of an Ni-Cr alloy, an intermediate melt-sprayed film of a ZrO2-Y2O3 composite body and an Ni-Cr alloy, and a surfacial melt-sprayed film of a ZrO2-Y2O3 composite body. CONSTITUTION:A film F for preventing sticking of welding spatter consisting of the three layers; an underlying melt-sprayed film 2 consisting of Ni-Cr alloy powder, an intermediate melt-sprayed film 3 consisting of a powder mixture composed of ZrO2-Y2O3 composite powder and Ni-Cr alloy powder and a surfacial melt-sprayed film 4 of ZrO2-Y2O3 composite powder is formed on the surface of a material 1 which is a ferrous material of a retaining jig C, etc. The above-mentioned film 4 is preferably formed of the composite powder prepd. by solutionizing 10-20wt% Y2O3 in ZrO2, and the film 3 is formed of the powder mixture prepd. by compounding 40-70% the ZrO2-Y2O3 composite powder solutionized with 10-20% Y2O3 in ZrO2 with the Ni-Cr alloy powder.

Description

Detailed Description of the Invention The present invention is designed to prevent welding spatter generated during T-work G welding or M-work G welding from welding to members such as work holding jigs around the welding torch. The present invention relates to a welding spatter adhesion prevention coating.

Conventionally, in order to prevent welding spatter from melting onto Wari I jigs made of iron-based materials, the jigs were coated with a spatter adhesion prevention paint containing alumina, water glass, and solvent as main components. There are known methods that form a chromium plating film or a chromium plating film that has low affinity for sputtering, but the coating film has low adhesion to the jig material and is also susceptible to heat caused by high-temperature sputtering and adhesion. It thermally deteriorates or carbonizes due to impact, and peels off in a relatively short period of time.Also, chrome plating film is effective in preventing spatter adhesion at the initial stage of use, but with repeated use, it may cause refilling and spatter welding. Heat due to adhesion 1fiE
In B, the plating film gradually deteriorates and peels off, making it unsuitable for long-term continuous welding work.

In order to eliminate such inconveniences, the present invention provides a welding spatter adhesion prevention coating with excellent peeling resistance for materials having a thermally sprayed coating made of zirconia-ittria composite powder on the surface layer, which is optimal for preventing sputter welding. This is the purpose of the iron-based material.
It consists of six layers: a base sprayed coating made of chromium alloy powder, an intermediate sprayed coating made of a mixed powder of zirconia-yttria composite powder and nickel-chromium alloy powder, and a surface sprayed coating made of zirconia-yttoria composite powder.

Next, one embodiment of the present invention will be explained based on the drawings.

Fig. 1 shows an apparatus for welding a pair of steel plates W, W constituting a motorcycle fuel tank, etc. In the figure, A is a welding torch, and B is the welding toe; 1i
lai'j #fc m'a:ZWA ”Cb°1゛I
7. The work holding jig C on both sides of the torch is used to hold the back bar D on both steel plates W on the jig E.

W was clamped and fixed, the core wire B was opposed to the joint portion of the two steel plates W, and M welding of the core portion was performed.

In this case, spatter scattered from the welding area tends to be deposited on the inner surface of the pressing jig C, so the welding spatter adhesion prevention coating F according to the present invention is formed on the inner surface.

The details of the coating F are as shown in Fig. 2, where a base thermal sprayed coating (2) of nickel-chromium alloy powder is applied to the surface of the material (1) of the presser jig C made of iron-based material. and zirconia-yttoria composite powder (ZrO2-y, o,)
An intermediate sprayed coating (3) made of a mixed powder of nickel and chromium alloy powder and a surface sprayed coating (4) made of a zirconia-yttoria composite powder are formed in six layers.

Zirconia has extremely low affinity for sputtering.
Although the thermal sprayed coating can effectively prevent spatter welding, it has the disadvantage that it is susceptible to thermal shock and is susceptible to cracking due to thermal shock caused by sputtering at a high temperature of 2000 to 2500''C.

In this case, it was confirmed that coating cracking could be effectively prevented by forming a thermally sprayed coating using a composite powder in which itria was added to zirconia as a solid solution. However, if the amount of ittria added was less than 10% by weight, The zirconia coating that forms the surface sprayed coating (4) has little effect, and if it exceeds 2% by weight, the thermal sprayed coating has a high affinity with sputtering and the spatter adhesion prevention effect tends to decrease for a while.
The amount of ittria added to the IJA composite powder is preferably 10 to 20% by weight.

Here, it is possible to directly spray the composite powder onto the surface of the material (1) to form a single-layer thermal sprayed coating, but the thermal sprayed coating has low adhesion to iron-based materials and is prone to peeling. Therefore, according to the present invention, a nickel-chromium alloy powder containing 20 to 50% by weight of chromium in nickel, which has a high adhesion to iron-based materials, is thermally sprayed onto the material (1) to form the base material as described above. A thermal sprayed coating (2) is formed, and the base thermal sprayed coating (2 consecutive 1 diagonal coatings) is formed. l) Both coatings (2) are formed due to the difference in thermal expansion coefficient from the surface sprayed ρ coating (4) made of composite powder. ) (4) In order to prevent the occurrence of cracks between the two coatings (2) and (4), an intermediate thermal spray coating is made of a mixed powder of nickel-chromium alloy powder and zirconia-yttria composite powder, which are the constituent materials of (41). (3), and the surface sprayed coating (4) forms these intermediate sprayed coatings (3).
) and the base thermal sprayed coating (2), the material is firmly bonded to the material (1), and its peeling resistance is improved.

Here, the mixed powder has an amount of IJA added of 10 to 10%.
It is preferable that 20% by weight of the zirconia-yttoria composite powder is blended with the nickel-chromium alloy powder in an amount of 40 to 70% by weight. That is, the blending ratio of the composite powder is 40 parts f? If it is less than c%, cracks are likely to form between the surface sprayed coating (3), and when it exceeds 70% by weight, cracks are likely to be formed between the base thermal sprayed coating (2) and the base thermal sprayed coating (2).

Example The surface of the material (1) of the work holding jig made of iron-based material was degreased with trichloroethane, and then the surface was blasted to have a satin-like rough surface, and then the surface was treated by plasma spraying. 6 layers of thermal spray coating under the conditions shown in the table (2) (3)
(4) was formed. Here, the thermal spraying material for the base thermal spray coating (2) is Niracurse chromium alloy powder containing 50% by weight of chromium, and the thermal spraying material for the surface thermal spraying coating (4) is 15% by weight of zirconia. An intermediate thermal spray coating (
For the thermal spraying material 3), a mixed powder was used in which the same nickel-chromium alloy powder as above was mixed with the same zirconia-yttoria composite powder as above in an amount of 50% by weight and 41%.

After completion of thermal spraying, the surface thermal sprayed coating (4) is finished by lapping with a diamond grindstone.

Using the work holding jig on which the film of the present invention was formed as described above, the untreated holding jig, the holding jig coated with Snow Quanta anti-adhesion paint, and the holding jig coated with chrome plating, the first When welding tests were conducted using the welding equipment shown in the figure, the following results were obtained. In addition, the welding test is 0.8
Using a φ welding core wire, current 70A, voltage 15~16■,
The welding was performed at a welding speed of 800 ras/min.

(1) Untreated holding jig - Spatter is firmly welded, and it is necessary to remove the spatter with a file every time five steel plates are welded.

・When welding 2,000 pieces, the jig will be deformed by the heat, so it will be necessary to correct the deformation.

・Jig life is limited to 200,000 sheets.

(11) Holder jig coated with paint - Spatter is not welded as firmly as in the case without treatment, but it is necessary to clean and remove spatter with a wire brush every five welds.

・The paint film partially peeled off after welding 100 sheets, and correction force was required.

・Complete repainting of the coating is required approximately once every 1,000 sheets.

・Jig life is limited to 500,000 sheets.

(]ii) Chrome-plated holding jig - It is necessary to clean and remove spatter with a wire brush every five welds.

・When welding 100 pieces, it is necessary to use a file to remove spatter that cannot be removed with a wire brush.

・Partial peeling of the plating film occurred after welding 2000 sheets.

・Jig life is limited to 500,000 sheets.

(＼,) The holding jig coated with the film of the present invention prevents welding of spatter, and air blowing every 10 welds allows the holding jig to be kept in the initial state of use.

・The sputter welding prevention effect does not deteriorate semi-permanently, and the film does not crack or peel.

・Jig life is extended to more than 1.5 million pieces.

As described above, according to the present invention, it is possible to obtain a coating with excellent peeling resistance that does not cause the welding of welding snags and ivy, and it is possible to form this coating on parts around the welding torch such as work holding jigs and hammers. This simplifies the work of removing scratches and ivy, allowing welding work to be carried out continuously and efficiently for long periods of time.
Furthermore, automation of the welding line becomes easy, and the lifespan of these parts can also be extended.

[Brief explanation of drawings]

FIG. 1 is a cut side view of a welding device showing an example of use of the present invention;
FIG. 2 is an enlarged cross-sectional view of the main part. (1)...Material (2)...Base sprayed coating (3)...Intermediate sprayed coating (4)...2 people outside the surface sprayed coating

Claims (1)

[Claims] 1. On the surface of the iron thread material, a base thermal spray coating of nickel-chromium alloy powder, an intermediate thermal spray coating of a mixed powder of zirconia-yttria composite powder and nickel-chromium alloy powder, and zirconia-chromium alloy powder are applied. A coating to prevent welding spatter adhesion, consisting of 6 layers, including a surface sprayed coating made of IJA composite powder. 2. The welding spatter adhesion prevention coating according to claim 1, wherein the zirconia-yttria composite powder forming the surface thermal sprayed coating is a mixture of zirconia and 1θ to 203i% yttria composite powder. 3 The mixed powder forming the intermediate thermal spray coating is Jill: I=7
[Zirconia-Ittria composite powder with 10 to 20% by weight of Ittria dissolved in nickel-chromium alloy powder 4
The welding spatter adhesion prevention coating according to claim 1 or 2, characterized in that it contains 0 to 70% by weight of tunic acid.