JPH0823062B2 - Ceramic coated blade manufacturing method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a blade made of ceramics for extending the life of a blade made of stainless steel.

[0002]

2. Description of the Related Art Knives and scissors have been conventionally used. Carbon steel and stainless steel have been used for metal knives such as knives, but carbon steel has a drawback that rust easily occurs, while stainless steel has excellent corrosion resistance. However, the hardness is insufficient, and when used repeatedly, there is a drawback that the cutting edge becomes worn and the sharpness becomes poor. Stainless steel with carbon content of 0.65 to 0.75 (S
FIG. 6 shows the results of the sag resistance test of a conventional blade according to US440A). The test results show that the cutting depth decreases by 45% after 40,000 repetitions. In addition, these metal blades have a problem that when they are used for cooking, the flavors are impaired because metal ions are emitted from the blades and adhere to food. Therefore, a blade having a surface coated with a ceramic coating is disclosed in JP-A-64-47849. Certainly, these ceramic-coated blades prevent wear of the blade edge and solve the problem of metal ions.

[0003]

However, the above-mentioned conventional ceramics-coated blades have a carbon content of 0.6-.
It is inexpensive because it uses 0.75% stainless steel as the base material, but Rockwell hardness (H _RC ).
Since only about 55 is obtained, there is a problem that it is easily worn and the durability of sharpness is poor. On the other hand, as shown in FIG. 7, as the tempering temperature becomes higher, the hardness of the substrate material decreases, so that the Rockwell hardness (H _RC ) is set to 5
There is a problem in that the coating temperature of the ceramics can be raised only up to about 350 ° C. if about 5 is secured. However, when the coating temperature is lowered, the adhesion to the substrate material decreases,
Further, since the film quality is also deteriorated, it is impossible with the prior art to obtain both properties in the best condition. The present invention has been made in view of the above-mentioned problems, and an object thereof is to provide a ceramic coating blade capable of obtaining high hardness as well as adhesion of a coating film and excellent film quality. .

[0004]

In the method for manufacturing a ceramic coated blade according to the present invention made in view of the above problems, the carbon content is 0.95 to 1.2% and the chrome content is 13 to 18%. The means for forming a ceramic coating film at 480 ° C. to 520 ° C. on the martensitic stainless steel (1) by the PVD method was taken.

[0005]

In the present invention, the carbon content is 0.95
A blade was formed using a martensitic stainless steel having a content of 1.2% and a chrome content of 13 to 18% as a material. Conventionally, the relationship between the tempering temperature and hardness of this martensitic stainless steel is that the temperature increases. It is said that the hardness decreases, and as a compromise, a coating temperature of around 350 ° C. was selected. However, it was found through experiments that the hardness increased from 400 ° C. and a peak of Rockwell hardness 59 appeared at 500 ° C. as shown in FIG. Therefore, in the present invention, by setting such a coating temperature to 500 ° C., the adhesion and film quality of the ceramic coating film layer could be made extremely good with almost no decrease in hardness.

[0006]

EXAMPLES Examples of the method for producing a ceramic coated blade of the present invention will be described in detail below. FIG. 1 is a sectional view of a kitchen knife manufactured by the above manufacturing method. In FIG. 1, reference numeral 1 denotes a blade base made of martensitic stainless steel as a base material, and a blade portion 2 is formed. And
3 is a PVD method (physical vapor deposition method) on the surface of the blade substrate 1
It is a ceramic coating film formed by. The martensitic stainless steel has a carbon content of 0.95 to 1.2 and a chrome content of 13 to 18%.
Of stainless steel. The properties of this stainless steel are illustrated. 2 is a graph showing the relationship between the quenching temperature and the hardness, and FIG. 3 is a graph showing the relationship between the tempering temperature and the hardness. As shown in FIG. 2, the blade of the present invention has a Rockwell hardness of 60 when quenched at 1050 ° C. Further, as shown in FIG. 3, the temperature characteristics of tempering are as follows:
The hardness starts to drop from around 200 ° C, but when it exceeds 400 ° C, the hardness starts to rise again and reaches a peak at 500 ° C, and when it exceeds 500 ° C, the hardness starts to drop again. Therefore, 480 ° C to 520 ° C is suitable as the ceramic coating temperature. Therefore, in the method for manufacturing a ceramic-coated blade according to the present invention, the condition of the hardness peak (temperature 500 ° C., Rockwell hardness 59) in FIG. 3 is set to the coating temperature, so that sufficient blade hardness and sufficient ceramics are obtained. Coating adhesion is obtained.

The ceramic-coated blade 1 thus manufactured can be quenched at 1050 ° C. because the substrate material is martensitic stainless steel, and by coating at 500 ° C., sufficient hardness ( Since the Rockwell hardness 59) is obtained, excellent sharpness is obtained, and since the temperature is higher than the conventional coating temperature, the adhesion and film quality of the ceramic coating layer to the base material are improved. That is, the effect of maintaining the sharpness for a long period of time can be obtained. This is because the abrasion resistance test results shown in FIG.
It also appears in the fatigue resistance test results shown in. Stainless steel with a carbon content of 0.65 to 0.75 (SUS
Fig. 6 shows the result of the conventional settling resistance test of a blade according to 440A).
Shown in From these test results, the conventional blade decreases 45% after 40,000 cycles, but the blade according to the present invention decreases only 10% after 40,000 cycles and 20% even after 80,000 cycles. I haven't. In this way, since excellent sharpness is maintained for an extremely long period of time, it is possible to obtain the effect of providing a high-quality blade. Moreover, since the surface is covered with ceramics, it is less rusty and easy to handle. The above ceramic coating is not limited to the titanium-based ceramic coating, and needless to say, may be a zirconia-based or chromium-based ceramic coating.

[0008]

According to the present invention, by coating at a high temperature of 480 ° C. to 520 ° C., the adhesion of the coating film to the material and the film quality are good, so that an excellent hardness of Rockwell hardness of 59 or more is obtained and the sharpness An effect that an excellent blade can be provided can be obtained. Further, since the blade is protected by the ceramics coating film by forming the titanium-based ceramics coating film by the PVD method, it is possible to maintain the excellent sharpness without deteriorating for a long period of time.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a kitchen knife manufactured by the method for manufacturing a ceramic-coated blade of the present invention.

FIG. 2 is a characteristic diagram showing the relationship between the quenching temperature and the hardness of the base material of the kitchen knife.

FIG. 3 is a characteristic diagram showing a relationship between tempering temperature and hardness of a base material of the kitchen knife.

FIG. 4 is a characteristic diagram showing the results of the wear resistance test of the blade of the present invention.

FIG. 5 is a characteristic diagram showing the results of the sag resistance test of the cutting tool of the present invention.

FIG. 6 is a characteristic diagram showing the result of a conventional settling tool sag resistance test.

FIG. 7 is a characteristic diagram showing a relationship between tempering temperature and hardness of a conventional substrate material.

[Explanation of symbols]

 1 Blade base 2 Blade 3 Ceramic coating

Claims (1)

[Claims] 1. A ceramic coating film is formed on a martensitic stainless steel having a carbon content of 0.95 to 1.2% and a chrome content of 13 to 18% by a PVD method at 480 ° C. to 520 ° C. A method for manufacturing a ceramics coated blade, characterized by: