JPH1129876A - Chromium oxide coated part, and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide inexpensive chromium oxide coated parts, having a coating layer composed essentially of chromium oxide on the surface of a metallic base material, capable of production in an extremely short time without deteriorating their excellent propeties, such as wear resistance, sliding characteristic, smoothness, corrosion resistance, heat resistance, insulating property, and adhesion strength, and their production. SOLUTION: In the chromium oxide coated parts constituted by forming a coating layer 5 composed essentially of chromium oxide on the surface of a metallic base material 4, the surface roughness of the surface of the metallic base material 4 is regulated to 0.1 to 0.3 μm on the basis of centerline average height (Ra) and also the thickness of the coating layer 5 composed essentially of chromium oxide is regulated to 1 to 2 μm. It is preferable that the chromium oxide coated parts are fiber handling parts.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chromium oxide coated component having a coating layer mainly composed of chromium oxide formed on the surface of a metal base material and a method for producing the same, and particularly to a good wear resistance, corrosion resistance and insulation. TECHNICAL FIELD The present invention relates to an inexpensive chromium oxide-coated component that can be manufactured in an extremely short time without deteriorating various properties such as properties, and a method for manufacturing the same.

[0002]

2. Description of the Related Art It has been attempted to apply a ceramic material having excellent wear resistance and heat resistance to various mechanical parts. However, ceramic materials are inherently brittle and have poor reliability against impact forces.
The use of parts made entirely of ceramic materials is
It is limited to narrow applications with little impact.

Therefore, a coating layer made of a ceramic material or another type of metal material is formed on the surface of a metal base material having high structural strength and toughness in order to impart properties such as wear resistance and corrosion resistance according to the intended use of the component. Surface-modified coated parts are used in many fields. For example, a piston,
For engine parts such as valves, rocker arms, push rods and automotive parts, heat resistance, wear resistance,
A coating layer made of a ceramic material such as Si ₃ N ₄ (silicon nitride), Cr ₂ O ₃ (chromia), ZrO ₂ (zirconia), and TiO ₂ (titania) is provided on the surface of the metal base material to provide heat insulation. There is a tendency to use coated parts formed by coating or the like.

[0004] Also, in pump parts such as plungers, cylinders, sleeves, and impellers of pumps, and bearing slide parts, coated parts in which a coating layer made of various ceramic materials is formed on the surface of a metal base material are becoming widespread.

Further, in a fiber handling part such as a fiber guide part, the thread is slid at a high speed, so that the part is severely worn. On the other hand, an acid or an alkali adheres to the thread at the time of spinning, and the part is susceptible to corrosion. Therefore, a coated component having a hard chromium plating layer having excellent wear resistance and corrosion resistance formed as a coating layer is used.

[0006] Among the coating layers made of the above-mentioned various materials, the coating layer mainly containing chromium oxide such as Cr ₂ O ₃ has heat resistance to withstand high temperatures up to about 600 to 1000 ° C. Because it has both excellent thermal shock resistance such as not peeling even when a cycle is added and excellent corrosion resistance to various chemical compounds,
Widely adopted.

A conventional coated part having a coating layer mainly composed of chromium oxide as described above has been manufactured, for example, by the following processing procedure. That is, a step of immersing a metal base material formed into a predetermined shape in a low-concentration chromic acid (CrO ₃ ) aqueous solution or applying the chromic acid aqueous solution to the surface of the metal base material; The step of heating and heating the base material at a temperature of 500 to 600 ° C. for 10 minutes to 1 hour is repeated about 15 to 20 times, whereby a thickness of 3 to 5 μm made of chromium oxide (Cr ₂ O ₃ ) or the like is obtained. A coated part having a degree of coating layer is produced.

[0008]

However, in the conventional chromium oxide-coated parts having the above-mentioned coating layer mainly composed of chromium oxide, the influence of the surface roughness of the metal base material is taken into consideration. In general, the coating layer was formed with a rough surface state, so even after the formation of the coating layer, the smoothness of the component surface was poor, the sliding characteristics were poor, and the wear resistance was insufficient. There was a problem.
In addition, since the adhesion strength between the metal base material and the coating layer is low, the coating layer is liable to peel off and the durability of the coated component is poor.

Further, in order to reduce the influence of the surface state of the metal base material, it is necessary to form the coating layer as thick as 3 to 10 μm. In addition, since a relatively low-concentration chromic acid aqueous solution prepared under normal temperature and normal pressure conditions was used as a raw material chromic acid aqueous solution for forming the coating layer, a single application and firing of this aqueous solution was performed. The thickness of the coating layer that can be formed by the operation is extremely small. Therefore, when the thickness is 3 to 10
In order to produce a coated part having a coating layer as thick as μm, the operation of applying and baking the above-described chromic acid aqueous solution to a metal base material has been repeated many times, such as 15 to 20 times.
Therefore, there has been a problem that the man-hours for manufacturing the coated parts are enormous, and the manufacturing cost is significantly increased.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a coated part having a coating layer mainly composed of chromium oxide on the surface of a metal base material, which has good wear resistance and sliding properties. Characteristics, smoothness, corrosion resistance, heat resistance, insulation,
It is an object of the present invention to provide an inexpensive chromium oxide-coated component that can be manufactured in an extremely short time without deteriorating properties such as adhesion strength, and a method for manufacturing the same.

[0011]

Means for Solving the Problems In order to achieve the above object, the inventors of the present invention have conducted a comparative study on the effects of the surface roughness of a metal base material and the thickness of a coating layer on various characteristics of a coated part. As a result, it has been found that a coated part can be manufactured in a very short time without deteriorating properties such as abrasion resistance, particularly when the surface roughness of the metal base material is defined in a predetermined range. That is, by accurately controlling the surface roughness of the metal base material to 0.1 to 0.3 μm on the basis of the center line average roughness (Ra), the thickness of the coating layer mainly composed of chromium oxide is reduced to 1 to It has been found that even when the thickness is as thin as 2 μm, it is possible to obtain, for the first time, a chromium oxide-coated component in which characteristics such as surface sliding characteristics, abrasion resistance, smoothness, and adhesion strength of the coating layer are not reduced.

In addition, by using a chromic acid aqueous solution having a higher chromic acid concentration than that of a saturated chromic acid aqueous solution at normal temperature and normal pressure as a raw material of the coating layer, the chromic acid aqueous solution can be coated once.・ The thickness of the chromium oxide coating layer formed by firing can be greatly increased, and the number of times of application and firing required to form a coating layer of a predetermined thickness can be reduced to three or less. There was found.

Further, it has been found that even when the above-described high-concentration chromic acid aqueous solution is applied to the surface of the metal base material and fired, a coated part having excellent properties such as wear resistance can be efficiently obtained. . The present invention has been completed based on the above findings.

That is, a chromium oxide-coated component according to the present invention is a chromium oxide-coated component in which a coating layer mainly composed of chromium oxide is formed on the surface of a metal base material.
The surface roughness of the metal base material surface is the center line average roughness (Ra)
The thickness is 0.1 to 0.3 μm on a standard basis, and the thickness of the coating layer containing chromium oxide as a main component is 1 to 2 μm.

The chromium oxide-coated part is suitable as a fiber handling part.

Further, in the method for producing a chromium oxide-coated part according to the present invention, the polishing is adjusted so that the surface roughness of the metal base material is 0.1 to 0.3 μm based on the center line average roughness (Ra). After that, the step of applying a chromic acid aqueous solution to the surface of the metal base material and the step of baking the metal base material coated with the chromic acid aqueous solution are repeated a plurality of times, so that a thickness of 1 It is characterized in that a coating layer of up to 2 μm is formed.

Further, it is preferable that the chromium oxide aqueous solution has a higher chromic acid concentration than a saturated chromic acid aqueous solution at normal temperature and normal pressure. In particular, the chromium oxidation aqueous solution
It is more preferable to have a chromic acid concentration higher than a saturated aqueous solution of chromic acid at 40 ° C. and normal pressure.

In the step of forming a coating layer having a predetermined thickness by using the above-mentioned high-concentration chromic acid aqueous solution, the step of applying the chromic acid aqueous solution to the surface of the metal base material includes the steps of: The number of repetitions of the step of baking the metal base material coated with is reduced to three or less.

Here, the metal base material is not particularly limited, and general-purpose structural steel materials, corrosion-resistant heat-resistant steels such as stainless steels, various iron-based alloys, carbon steels, titanium alloys, aluminum alloys, Inconel and the like can be used. . The shape of the metal base material is determined according to the use of the component.

The chromium oxide has an average particle size of 0.1.
1 to 1.0 μm chromic oxide (Cr ₂ O ₃ ) fine particles. This coating layer mainly composed of chromium oxide has a deep dark green color.

Further, since the average particle size of the chromium oxide constituting the coating layer is as fine as 0.1 to 1.0 μm as described above, the surface roughness of the coating layer has a center line average roughness (Ra). It is preferably formed on the surface of the metal base material having a range of 0.1 to 0.3 μm on a standard basis. Specifically, before forming the coating layer, the surface of the metal base material is polished and then subjected to barrel processing or buffing to adjust the Ra base to 0.1 to 0.3 μm, and thereafter the coating layer is formed. To form By adjusting the surface of the metal base material to the range of 0.1 to 0.3 μm on the basis of Ra in this manner, even if the thickness of the coating layer is as thin as 1 to 2 μm, the sliding characteristics and wear resistance are good. In addition, at the same time as increasing the bonding strength with the coating layer, the surface roughness of the chromium oxide-coated component after the formation of the coating layer can be reduced, and the smoothness can be improved. However, the surface roughness on the basis of Ra is 0.
If it exceeds 3 μm, it becomes difficult to form a coating layer uniformly, so that it is preferably 0.3 μm or less.

More specifically, when the metal base material is an iron-based metal, a reaction layer of an iron compound and chromium oxide is provided between the metal base material and the coating layer containing chromium oxide as a main component. Preferably, it is formed. By forming this reaction layer, the bonding strength between the coating layer containing chromium oxide as a main component and the metal base material can be further increased. In the present invention, "the coating layer mainly composed of chromium oxide is formed on the surface of the metal base material" means that even if the coating layer is formed via the reaction layer, it is within the scope of the present invention. Needless to say. Also, on the surface of the metal base material, apart from whether the interface is clear or not, substantially a two-layer coating layer of the reaction layer and a coating layer mainly composed of chromium oxide is formed. Become.

The coating layer containing chromium oxide as a main component can be formed by, for example, the following procedure. That is, first, to prepare a concentration of 50 to 90% by weight of chromic acid (CrO ₃₎ solution. As this chromic acid aqueous solution, use a high concentration chromic acid aqueous solution having a higher chromic acid concentration than a saturated aqueous solution of chromic acid at normal temperature and normal pressure, particularly a higher chromic acid concentration than a saturated aqueous solution of chromic acid at 40 ° C. and normal pressure. Is preferred.

That is, the saturated chromic acid concentration at a normal pressure and a temperature of 40 ° C. is 1.5 times or more the saturated chromic acid concentration at a normal temperature (25 ° C.) and normal pressure. By using such a high-concentration chromic acid aqueous solution, it is possible to increase the thickness of the chromium oxide coating layer formed by a single application and firing operation of the chromic acid aqueous solution. Therefore, the number of repetitions of the application and firing operations of the aqueous solution of chromic acid required to form the chromium oxide coating layer having a predetermined thickness can be significantly reduced.

Incidentally, in the case of forming a coating layer having the thickness specified in the present invention by using a high-concentration chromic acid aqueous solution as described above, a step of applying a chromic acid aqueous solution to the surface of the metal base material and The number of repetitions of the step of firing the metal base material coated with the acid aqueous solution can be reduced to three times or less, and the number of man-hours (manufacturing cost) for manufacturing coated parts can be greatly reduced.

Next, the chromic acid (Cr
An O ₃ ) aqueous solution is applied or immersed on the surface of a metal base material such as an iron-based metal whose surface roughness has been adjusted in advance, thereby adhering or impregnating the surface of the metal base material with a chromic acid aqueous solution. Next, by heating and baking at a low temperature of about 400 to 600 ° C., water is evaporated, and at the same time, a reaction layer formed by a chemical reaction between chromium oxide and the surface layer of the metal base material is formed. chromium oxide comprising fine particles of .1～1.0Myuemu (chromic oxide: Cr ₂ O ₃₎ coating layer mainly composed of are formed. By repeating the adhesion impregnation operation and the heating and firing operation a plurality of times, a coating layer having a predetermined thickness is formed, and a chromium oxide coated part having a dense and smooth coating layer on the surface is obtained.

If the thickness of the coating layer is less than 1 μm, the effect of improving abrasion resistance, sliding characteristics, smoothness and bonding strength is poor.
The number of repetitions of the impregnation operation and the firing operation increases,
It is not economical because the number of man-hours for manufacturing coated parts increases rapidly.

If the operation of applying and impregnating the chromic acid aqueous solution and the sintering operation are performed only once, fine pores are likely to remain in the coating layer. The firing operation may be repeated a plurality of times. The thickness of the coating layer can be adjusted by controlling the number of repetitions of the application / impregnation operation and the baking operation.

The coating layer formed as described above has high bonding strength to the metal base material, high hardness, no pores, wear resistance, low friction (sliding characteristics), heat resistance, and smoothness. , Corrosion resistance,
It has excellent insulation properties. Incidentally, the surface hardness when stainless steel is used as the metal base material is 1500 to 2000 Hv.
(0.1) and a hardness similar to that of a cemented carbide can be obtained.

In particular, when an iron-based metal base material is used, chromium oxide and metal (iron) undergo a chemical reaction at the boundary between the coating layer and the metal base material to form a reaction layer. Due to the presence of the layer, the joint strength between the two is 700 kgf / cm ² (68 kgf / cm ² ).
MPa) or more.

Further, the chromium oxide (C
Since the average particle size of r ₂ O ₃₎ fine particles are 0.1~0.5μm about and ultrafine, strong action as a solid lubricant.
For this reason, the coefficient of friction on the component surface is reduced, and the effect of improving the sliding characteristics is remarkable. In particular, since the coating layer is formed by precipitation from an aqueous solution, the constituent particles are ultrafine, and unlike a porous ceramic coating formed by a conventional thermal spraying method, corrosion resistance and wear resistance do not become insufficient.

Further, since the entire coating layer is formed densely, it is excellent in heat resistance and thermal shock resistance. Even when repeated thermal cycling acts on the chromium oxide coated part, the coating layer is hardly peeled off. There is little dusting due to peeling.

Further, the coating layer has excellent corrosion resistance to acidic solutions such as sulfuric acid, basic solutions such as aqueous ammonia, and organic solvents such as alcohol, acetone, and gasoline. Has excellent durability. The chromium oxide-coated component according to the present invention exhibits excellent durability when applied to a fiber handling component such as a heald that slides over a long period of time with a fiber to which a chemical agent or the like has adhered.

Further, by forming the coating layer, the function of the metal base material can be greatly enhanced, and this chromium oxide-coated component can be used especially for an adsorption cylinder of a die bonder device or a lead frame presser of a wire bonding device. Excellent effects are exhibited even when used as a constituent material of a semiconductor component fixing jig.

Further, since the coating layer has a dark green color, when this chromium oxide-coated component is used, for example, as an adsorption cylinder of a die bonder, the contrast between the semiconductor element and the adsorption cylinder serving as the background thereof is increased. And the shape and position of the semiconductor element are clearly recognized by a monitor device such as a TV camera. Therefore, the recognition error of the semiconductor element by the monitor device is reduced, and the semiconductor component can be assembled with high accuracy.

According to the chromium oxide-coated component having the above structure, the surface roughness of the metal base material is adjusted to 0.1 to 0.3 μm on the basis of the center line average roughness (Ra). Oxide coated parts that do not decrease in properties such as surface sliding properties, wear resistance, smoothness, and adhesion strength of the coating layer even when the thickness of the coating layer mainly composed of a material is extremely thin as 1 to 2 μm. Can be obtained in a short time.

In addition, by using a chromic acid aqueous solution having a higher chromic acid concentration than a saturated chromic acid aqueous solution at normal temperature and normal pressure as a raw material of the coating layer, it is possible to apply the chromic acid aqueous solution at one time. -The thickness of the chromium oxide coating layer formed by firing can be greatly increased, and the number of times of application and firing required to form a coating layer of a predetermined thickness can be reduced to 3 or less. In addition, the number of man-hours for manufacturing coated parts is greatly reduced, and low-cost, low-cost coated parts can be mass-produced.

[0038]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a chromium oxide coated part according to the present invention will be described below with reference to the accompanying drawings. Particularly, an embodiment in which a chromium oxide coated part is applied to a heald used in a loom will be described.

The heald 1 used for the loom is provided with a thread insertion hole 2 generally called a perforated hole for inserting a warp (warp) at the center as shown in FIG. 1, and a frame body at both ends. Mounting holes 3 and 3 for inserting a heald bar for mounting the

A plurality of healds 1 are arranged in parallel with the frame and attached via a heald bar. The heald 1 is moved integrally by the up and down movement of the frame to cause up and down vibration to the warp passing through the thread insertion hole 2. give. At this time,
The mounting holes 3, 3 provided at both ends of the heald 1 are in sliding contact with the metal heald bar, while the thread insertion holes 2 provided in the central portion are in sliding contact with the warp. For this reason, the attachment holes 3 and 3 of the heald 1 are significantly worn due to friction with the heald bar, and then are broken, so that the heald may fall off the heald bar.

The surface of the thread insertion portion 2 of the heald 1 is scratched by friction with the warp passing therethrough, and the scratches cause "warping" of the warp yarn to lower the texture of the woven fabric. In some cases. Further, on the surface of the heald 1, water droplets used for the water jet method adopted for moving the weft thread adhere, and foreign matters contained in the water react with the metal material constituting the heald 1 to cause the heald surface Easily adheres to the surface as a foreign material layer. Then, the foreign material layer becomes thick due to an increase in the attachment of the foreign material, comes into contact with the foreign material layer of another adjacent heald, and causes a hindrance of the operation of the heald.

Therefore, conventionally, a plating method, a PVD (physical vapor deposition) method, a CVD (chemical vapor deposition) method,
Healds in which a coating layer is integrally formed by using a thermal spraying method or the like have been frequently used, but those which are sufficiently satisfactory in durability and manufacturing cost have not been obtained.

An example in which the chromium oxide-coated part according to the present invention is applied to a heald will be specifically described with reference to the following examples.

Examples 1 to 6 A predetermined amount of chromic acid (CrO ₃ ) was weighed, mixed with water, and then subjected to stirring dissolution treatment to prepare chromic acid aqueous solutions having the concentrations shown in Table 1, respectively.

On the other hand, as shown in FIG. 1, a large number of heald bodies made of stainless steel having a length of 302 mm, a width of 2 mm and a thickness of 0.3 mm as a metal base material are prepared, and the surface of the heald body is polished and then buffed. And the surface roughness was adjusted as shown in Table 1. Next, after each of the above-mentioned chromic acid aqueous solutions was adhered to the surface of the heald body by a dipping method, firing was performed at a temperature of 550 ° C. Table 1 shows the adhesion / firing treatment in which the above-described chromic acid aqueous solution adhering step and firing step are one cycle.
By carrying out the number of times shown in Table 1, a coating layer having a thickness shown in Table 1 was integrally formed, and healds as chromium oxide coated parts according to Examples 1 to 6 were manufactured.

The surface of the heald 1 according to each embodiment is shown in FIG.
As shown in FIG. 2, a coating layer 5 is integrally formed on the surface of the metal base material 4, and the coating layer 5 is made of fine chromium oxide (Cr ₂ O ₃ ) particles having an average particle size of 0.1 to 0.5 μm. The chromium oxide layer 6 and the reaction layer 7 formed by a chemical reaction between chromium oxide and the iron component of the metal base material 4 were formed.

Comparative Example 1 On the other hand, the surface roughness of the heald body was made as large as 3 μm on the basis of the center line average roughness (Ra) as in the prior art, while the coating and baking treatment was performed using a low-concentration chromic acid aqueous solution. Was repeated a number of times to form a thick coating layer as shown in Table 1, except that the slurry was applied and fired under the same conditions as in Examples 1 to 6 to prepare a heald according to Comparative Example 1. did.

Comparative Examples 2 to 5 A Cr plating layer (Comparative Example 2), a Ni plating layer (Comparative Example 3), and a Zr layer having the thicknesses shown in Table 1 were formed on the surface of a heald body made of stainless steel as a metal base material. By forming a plating layer (Comparative Example 4) and a Zn plating layer (Comparative Example 5), healds as coated parts according to Comparative Examples 2 to 5 were prepared.

With respect to each heald of each of the examples and comparative examples thus prepared, the bonding strength (peel strength) of the covering layer was measured, and the heald was attached to the frame through a heddle bar in the mounting hole of each heddle. After actually mounting the loom on the loom and operating the loom for a total of 2,000 hours, the wear amount of the holes of each heald was measured. In addition, the defect occurrence rate of the woven fabric caused by the wear of the heald during the operation time was measured. In addition, for each heald, the number of manufacturing steps required from the preparation stage of the constituent material of the coating layer to the completion stage of integrally forming the coating layer was measured, and the results shown in Table 1 below were obtained.
Note that the above man-hours are reference values (100) for Comparative Example 1.
As relative display.

[0050]

[Table 1]

As is clear from the results shown in Table 1 above,
According to the heald according to each embodiment, since the surface roughness of the metal base material is adjusted to 0.1 to 0.3 μm based on the center line average roughness (Ra), the coating mainly composed of chromium oxide is used. Even when the thickness of the layer is extremely thin as 1 to 2 [mu] m, a heald is obtained in which characteristics such as surface sliding properties, abrasion resistance, smoothness and adhesion strength of the coating layer are not reduced.

In addition, by using a chromic acid aqueous solution as a raw material of the coating layer, particularly a high concentration chromic acid aqueous solution, the chromic oxide coating layer formed by one application and firing of the chromic acid aqueous solution is used. The thickness can be greatly increased, and the number of repetitions of coating and firing required to form a coating layer having a predetermined thickness can be reduced to 3 or less, so that chromium oxide (Cr ₂ O ₃ ) can be reduced. It has been found that the coating layer containing the main component can be easily and quickly formed, and the manufacturing cost of the heald can be greatly reduced.

Further, the heald coating layer according to each embodiment has a dense structure containing fine chromium oxide (Cr ₂ O ₃ ), so that the coating layer itself has high structural strength and excellent peel strength. It was found that the durability was good.

On the other hand, in the case where the surface roughness of the heald body (metal base material) is large as in the conventional comparative example 1, a thick coating layer is required to obtain predetermined wear resistance and slidability. It was again confirmed that the number of repetitions of the application and baking of the chromic acid aqueous solution was increased, so that the production cost increased.

Further, according to the heald according to each of the examples, as compared with the conventional healds shown in Comparative Examples 2 to 5, the occurrence rate of the warp fuzz is significantly reduced, and the quality of the woven fabric is improved. , The yield improved. Further, it was also found that the healds of the examples were excellent in abrasion resistance, could maintain the smoothness set at the time of manufacture for a long period of time, and could effectively prevent the attachment of foreign substances.

Furthermore, the coating layer used for the heald in each of the examples had good adhesion to the metal base material, and the occurrence of cracks and peeling due to the movement of the heald was small. Also,
Since the coating layer was extremely thin, the rigidity of the metal base material was not impaired, and the quality of the woven fabric was equal to or higher than that of the conventional one.

[0057]

As described above, according to the chromium oxide coated part of the present invention, the surface roughness of the metal base material is adjusted to 0.1 to 0.3 μm on the basis of the center line average roughness (Ra). Therefore, the thickness of the coating layer mainly composed of chromium oxide is 1 to
Even when the thickness is as thin as 2 μm, a chromium oxide-coated part in which characteristics such as surface sliding properties, abrasion resistance, smoothness, and adhesion strength of the coating layer are not deteriorated can be obtained in a short time.

Further, by using a chromic acid aqueous solution having a higher chromic acid concentration than that of a saturated chromic acid aqueous solution at normal temperature and normal pressure as a raw material of the coating layer, the chromic acid aqueous solution can be applied once. -The thickness of the chromium oxide coating layer formed by firing can be greatly increased, and the number of times of application and firing required to form a coating layer of a predetermined thickness can be reduced to 3 or less. In addition, the number of man-hours for manufacturing coated parts is greatly reduced, and low-cost, low-cost coated parts can be mass-produced.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of a chromium oxide-coated component according to the present invention, which is applied to a heald of a weaving machine.

FIG. 2 is an enlarged sectional view of a portion II in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Chromium oxide coating part (held) 2 Thread insertion hole 3 Mounting hole 4 Metal base material (stainless steel) 5 Coating layer 6 Chromium oxide layer 7 Reaction layer

Claims (6)

[Claims] In a chromium oxide-coated component having a coating layer mainly composed of chromium oxide formed on the surface of a metal base material, the surface roughness of the surface of the metal base material is determined by a center line average roughness (Ra). 0.1 to 0.3 μm as standard, and the thickness of the coating layer containing chromium oxide as a main component is 1 to 2 μm.
m. 2. The chromium oxide coated part according to claim 1, wherein the chromium oxide coated part is a fiber handling part. 3. After polishing and adjusting the surface roughness of the metal base material to be 0.1 to 0.3 μm based on the center line average roughness (Ra), an aqueous solution of chromic acid is applied to the surface of the metal base material. A step of repeating the step of applying and the step of firing the metal base material to which the aqueous chromic acid solution has been applied a plurality of times to form a coating layer having a thickness of 1 to 2 μm containing chromium oxide as a main component; A method for producing an oxide-coated part. 4. The method for producing a chromium oxide-coated component according to claim 3, wherein the chromium oxide aqueous solution has a higher chromic acid concentration than a saturated chromic acid aqueous solution at normal temperature and normal pressure. 5. The method for producing a chromium oxide-coated component according to claim 3, wherein the chromium oxide aqueous solution has a higher chromic acid concentration than a saturated chromic acid aqueous solution at 40 ° C. and normal pressure. 6. The method according to claim 3, wherein the step of applying a chromic acid aqueous solution to the surface of the metal base material and the step of firing the metal base material coated with the chromic acid aqueous solution are repeated three times or less. A method for producing the chromium oxide-coated part as described above.