JP3130220B2 - Conductor roll for electroplating line and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conductor roll for an electroplating line, and more particularly to a conductor roll excellent in corrosion resistance and abrasion resistance and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, conductor rolls used for electroplating equipment of zinc, tin, etc., are less likely to be eroded by a plating solution in order to prolong the life as a roll, and have abrasion resistance. Are required.

As a conductor roll for electroplating that meets these requirements, the inventors of the present invention have previously proposed a conductor roll described in Japanese Patent Publication No. 61-21320. This conductor roll coats the surface of the roll body by spraying and re-melting a mixed powder composed of 10 to 90% by weight of a metal carbide powder and the balance being a Ni-Cr-based self-fluxing alloy powder. Manufactured as a requirement, the coating formed by thermal spraying has a structure in which spherical metal carbide particles are randomly dispersed in a Ni—Cr-based alloy.

[0004] The above conductor roll has good corrosion resistance because the roll surface film is jointed with a Ni-Cr alloy, and in addition, has high wear resistance due to metal carbide particles dispersed in the film. It was formed on a conductor roll for plating lines. This roll was more than five times as durable as the conventional conductor roll plated with Cr. However, it has been found that if used for a long time, the metal carbide particles fall off, foreign matter adheres to the pits after falling off, and there is a problem that a press scratch is generated on the steel plate to be plated.

In order to solve such problems, the present inventors further proposed a conductor roll for an electroplating line described in Japanese Patent Application Laid-Open No. 5-9699. This conductor roll is made by adding WC to Ni-Cr based self-fluxing alloy powder.
The powder mixed in the range of ~ 80% by weight is sprayed so that the WC particles are deformed into an elliptical shape and the major axis of the WC particles is arranged in parallel with the coating layer. To form a coating layer which is less likely to cause problems due to the WC particles falling off. Thus, the conductor roll described in JP-B-61-21320 described above can be used. Continuous use with more than twice the life has become possible.

However, since the above-mentioned roll has a high re-melting treatment temperature of about 1100 ° C. after thermal spraying, the roll has a high temperature.
The base metal tends to deteriorate or be deformed, and there has been a problem that a great deal of cost is required for the countermeasure.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a conductor roll for an electroplating line formed by spraying a Ni-Cr-based self-fluxing alloy containing metal carbide particles. It is an object of the present invention to provide a sprayed coating with a performance comparable to that of a conventional remelted product in a state of being sprayed without performing remelting.

[0008]

Means for Solving the Problems The conductor roll for electroplating of the present invention, which has been intensively studied for solving the above-mentioned problems, is provided directly on a roll body surface or on a roll. A base spraying layer made of an alloy containing no metal carbide is provided on the body surface, and WC is formed on the base spraying layer.
Sprayed a mixed powder consisting of Ni-Cr alloy and Ni-C
A structure in which flat-dispersed WC particles are scattered and formed in joints where the r-based alloy particles are consolidated.

[0009] The structure of this roll manufacturing method is the same as that of
Thermal spraying of mixed powder composed of C and Ni-Cr alloy
A method for producing a conductor roll for an electroplating line in which a film is formed on the surface of
Using 90μm powder, while feeding the powder at 10 ~ 20kg / hr, the spray pressure at the spray pressure of 1.0 ~ 1.5MPa and spraying at a spray particle speed of 500 ~ 1000m / sec, characterized in that Then, a base sprayed layer made of an alloy containing no metal carbide may be provided on the roll body surface in advance, and the above method may be applied on the base sprayed layer.

[0010] That is, the inventors of the present invention, WC and Ni-
When spraying a mixed powder of a Cr alloy, the degree of melting of the sprayed particles is set to a level at which the fluidity containing only a small amount of the molten phase is about to be lost just before solidification, and the sprayed particles collide with the target surface at high speed Then, based on the idea that the above-mentioned particles are firmly bonded and integrated and a dense film strongly bonded to the base material is obtained, a conductor for an electroplating line can be obtained.
As a result, it was found that if the particle size of the sprayed material and the spraying conditions were limited as described above, the desired durability could be obtained, and the present invention was achieved.

The thermal spraying material used in the present invention may be composed of a conventionally known WC of 20 to 80% by weight and a balance of a Ni--Cr alloy. By selecting the WC content according to the use conditions within the above range as a guide and achieving a balance between corrosion resistance and abrasion resistance, excellent overall durability can be obtained.

Regarding the particle size of the sprayed material, alloy particles smaller than 40 μm are melted quickly, and it is difficult to obtain the above-mentioned degree of melting required for the present invention. On the other hand, alloy particles larger than 90 μm are projected unmelted. In addition to the generation of particles, WC particles also have a problem of shedding during use as described above.

In the present invention, the above-mentioned sprayed material is sprayed at a normal frame temperature of 2500 to 3500 ° C. In order to obtain the above-mentioned degree of melting, the feeding of the material is also performed under the spraying conditions. The quantity (feed rate) must be greater than normal spraying, and the time that the sprayed material remains in the frame is not too long. On the other hand, if the feed rate is excessive or the residence time is extremely short, no melting occurs. Therefore, the supply amount is larger than 10 kg / hr, which is conventionally regarded as suitable.
The particle velocity related to the residence time was set to 500 to 1000 m / sec, compared to the conventional 200 to 1000 m / sec. In order to inject such a large amount of sprayed material having a large particle size at a high speed, it is necessary to increase the amount of 1.0 by 1.0, which is significantly higher than the conventional 0.2 to 0.6 MPa.
A large combustion pressure of ~ 1.5MPa is required.

The particle speed of 500 to 1000 m / sec is such that particles having properties similar to a solid whose melting degree is adjusted as described above are caused to collide with the roll surface at a high speed, and the particles are mixed with each other or with the base material. It has been confirmed that it is also appropriate as a speed condition for performing integration between the two.

In order to specify the above conditions, a test peak
Table 1 shows the results of the frame spraying experiment performed using the above-described method. As can be seen from Table 1, by applying a particle speed of 500 to 1000 m / sec to the sprayed material fed at 10 to 20 kg / hr, favorable film properties can be obtained, and particles projected in large quantities are well fixed. Also, the spray efficiency was excellent.
Further, it has been found that the combustion pressure suitable for imparting the above-mentioned particle velocity to the sprayed material fed as described above is in the range of 1.0 to 1.5 MPa.

[0016]

[Table 1]

In the present invention configured as described above,
When the amount of WC in the thermal spray material increases, the bonding strength with the base material tends to decrease. In such a case, by performing base thermal spraying with an alloy powder not containing a metal carbide such as WC, a favorable A film is obtained. It is desirable that the base thermal spraying be performed under the above-described thermal spraying conditions for the material containing WC.

[0018]

According to the conventional thermal spraying method described in Japanese Patent Laid-Open No. 5-9699, as shown in FIGS. 3 and 4, the coating layer 4 formed on the roll body 1 by thermal spraying is melted. The flattened particles 2 and 3 (metal carbide particles 2 and Ni-
It has a structure in which a Cr-based alloy 3) is laminated. That is,
Even when the film was formed, a considerable amount of the molten phase remained and was flattened because it had sufficient fluidity. Therefore, since the reaction force during lamination was small, the flat grains 2 and 3 were completely integrated. It does not mean that there are microscopic gaps between the grains. Further, a tensile stress due to the solidification shrinkage of the molten phase remains in the film, and the adhesive force and the bonding force between the particles are weak, so that the thermal spraying cannot withstand use.

Therefore, in the above-mentioned conventional method, the film is melted and solidified by subjecting the film to a remelting treatment.
A densified film as shown in FIGS. 5 and 6 is obtained. However, this re-melting process requires a processing temperature of 1100
As described above, there is a problem that deterioration of the base material and dimensional change become a problem due to a high temperature of about ° C., and that the cost is increased due to this countermeasure.

On the other hand, in the present invention, 2500 to
At a normal frame temperature of 3500 ° C., by regulating the particle size of the thermal spray material powder and the feed rate of the powder as described above, the degree of melting of the thermal spray particles can be reduced to a level where the molten phase immediately before solidification is extremely small. It contains only a small amount and has a level at which fluidity is about to be lost. Further, by impinging the sprayed particles against the roll body at the high speed, the particles are mutually compressed between the particles or between the particle base materials at the time of the collision. A matching force is generated, and even though this is a very small amount, it occurs in the coexistence of molten metal that plays the role of a binder, so that a solidification state similar to pressure sintering and a strong bond with the base material occur It is done.

The film thus obtained is shown in FIGS.
As shown in FIG. 3, the Ni—Cr alloy 3 forms a dense joint in which the grains are integrated, and the WC particles 2 dispersed flat by the strong compressive force at the time of the collision in the joint. Are arranged parallel to the surface to form a scattered structure. Moreover, the solidification that occurs in the coating only finally solidifies the molten metal, which contains only a very small amount, and does not cause significant shrinkage, while the mother is under the action of the strong mutual compressive force described above. Due to the large heat capacity of the base material due to contact with the material, the solidification of the minimal amount of molten phase is completed almost instantaneously, so that the compressive force is frozen, and a compressive stress similar to shot peening remains. .

That is, in the present invention, the regulation of the particle size of the thermal spraying material powder, the amount of the thermal spraying material (feeding speed), the thermal spraying particle speed, and the combustion pressure for realizing these are combined. For example, if the above-mentioned feed rate is below the lower limit in the present invention, the melting of the particles proceeds too much, not only the film is not obtained, but also the particles are scattered at the time of collision. Will occur.

[0023]

Embodiments Embodiments of the present invention are as shown in Table 2. This example is for confirming the effects of the present invention, and the present invention is not limited to this example. Here, the present invention is applied to a conductor roll of a halogen method electroplating line, and a roll of the present invention and a conventional roll in which a film is formed on a roll having the same specifications by a conventional technique.
And compared. FIG. 1 is a cross-sectional view of an example of a sprayed coating (as sprayed) formed by the method of the present invention, FIG. 2 is a partially enlarged view of the coating in FIG. 1, and FIG. 3 is a conventional sprayed coating (as sprayed). ), FIG. 4 is a partially enlarged view of the coating of FIG. 3, FIG. 5 is a cross-sectional view of a conventionally proposed sprayed coating after remelting, FIG. 6 is a partially enlarged view of the coating of FIG. In the figure, 1 indicates a roll body, 2 indicates metal carbide particles (WC particles), 3 indicates a Ni-Cr alloy, and 4 indicates a film.

As is apparent from Table 2, the roll of the present invention is obtained by applying a sprayed coating with the particle size of the sprayed material powder, the amount of powder fed, the combustion pressure and the particle speed being respectively higher or higher than those of the conventional one. Despite the same sprayed material, despite the fact that it has not been remelted, it has the same durability as the conventional product that has been remelted, and the cost reduction effect by omitting the remelting process is remarkable It is.

The reason why such a durability was obtained by the coating as it was sprayed with the roll of the present invention is that the WC particles were contained in the solidified dense Ni--Cr alloy joint as shown in FIG. It is thought to be due to the form of the film that is present in a flatly dispersed state and the compressive stress remaining in the film.

[0026]

[Table 2]

[0027]

The present invention is as described above, and has the same corrosion resistance as a roll which has been subjected to re-melting after thermal spraying according to the conventional method.
Conductor for electroplating line with excellent wear resistance
Can be obtained as it is without thermal spraying and without re-melting, so that it can be manufactured at low cost.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an example of a thermal spray coating (as sprayed) formed by the method of the present invention.

FIG. 2 is a partially enlarged view of the coating of FIG.

FIG. 3 shows a conventionally proposed thermal spray coating (as sprayed)
Sectional drawing of an example of FIG.

FIG. 4 is a partially enlarged view of the coating of FIG.

FIG. 5 is a cross-sectional view of a conventionally proposed thermal spray coating after a remelting process.

FIG. 6 is a partially enlarged view of the coating of FIG.

[Explanation of symbols]

 1 Roll body 2 Metal carbide particles (WC particles) 3 Ni-Cr alloy 4 Coating

──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Satoru Midorikawa 1 Kawasaki-cho, Chuo-ku, Chiba-shi, Chiba Kawasaki Steel Corp. Chiba Works (58) Field surveyed (Int. Cl. ⁷ , DB name) C23C 4 / 04 C25D 7/06

Claims (3)

(57) [Claims] An undercoat sprayed layer made of an alloy containing no metal carbide is provided directly on the surface of the roll body or on the surface of the roll body, and WC and Ni-Cr are formed on the undercoat sprayed layer. A conductor powder for an electroplating line characterized by forming a structure in which flat-dispersed WC particles are scattered in joints where Ni-Cr-based alloy particles are solidified by spraying a mixed powder composed of a base alloy. - 2. A method for producing a conductor roll for an electroplating line in which a mixed powder composed of WC and a Ni—Cr alloy is sprayed to form a film on the surface of a roll body, wherein the powder has a particle size of 40 to 90 μm. Using powder of 10-20k
g / hr and the combustion pressure inside the sprayer is 1.0-1.5
A method for producing a conductor roll for an electroplating line, wherein spraying is performed at a spraying particle speed of 500 to 1000 m / sec as MPa. 3. The method of claim 2, wherein an alloy powder containing no metal carbide is sprayed on the surface of the roll body to form a base sprayed layer, and the method of claim 2 is applied on the base sprayed layer. For producing a conductor roll for an electroplating line.