JPH1033847A - Cutlery material having excellent corrosion resistance and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the hardness in the part of a blade edge and to improve the corrosion resistance over the entire part by coating both surfaces of an intermetallic compd. of Ni and Al, such as NiAl.Ni3 Al, in the central part with a precipitation hardening type Ni alloy. SOLUTION: The intermetallic compd. of Ni and Al is formed by holding an Al sheet or Al alloy sheet between precipitation hardening type Ni alloy sheets and subjecting these sheets to rolling and press welding, then heating the same. This compd. is subjected to precipitation hardening, by which the cutlery consisting of the materials treated in such a manner is formed. The precipitation hardening type Ni alloy includes an Ni alloy consisting, by weight % (hereafter the same), 2% Be and the balance Ni, Ni alloy consisting of 2% Be, 3% Al and the balance Ni, etc. The Al alloy to be used includes an Al alloy consisting of 5% Cu and the balance Al, etc. The heating temp. for forming the intermetallic compd. of Ni and Al and subjecting the compd. to precipitation hardening is specified to 400 the 800 deg.C and in the case of the precipitation hardening type Ni alloy consisting of 2% B and the balance Ni, this temp. is specified to 400 to 650 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blade material excellent in corrosion resistance and a method of manufacturing the same, and more particularly, to a blade material in which both surfaces of an intermetallic compound of Ni and Al are coated with a precipitation hardening type Ni alloy and a method of manufacturing the same. About.

[0002]

2. Description of the Related Art Conventionally, as a material for a cutting tool, generally, a JISS comprising C: 1.00 to 1.30%, Si: 0.35% or less, Mn: 0.50% or less, and the balance Fe
K1 or SK2 carbon tool steel is used. If higher hardness is required, C: 0.6%, Cr: 4.4%
% JIS SKD cold tool steel consisting of the balance Fe.

When corrosion resistance and high hardness are required, C: 0.26 to 0.40%, Si: 1.0% or less, Mn: 1.0% or less, Cr: 12 to 14% , The rest F
e, a martensitic stainless steel such as SUS420J2 is used, and when higher hardness is required, C: 0.80 to 0.90%, Si: 0.
40%, Mn: 0.40%, Cr: 3.80 to 4.50
%, Mo: 4.50-5.50%, W: 5.50-6.
A high-speed tool steel such as JISSKH51 comprising 70%, V: 1.00 to 2.20% and the balance Fe was used.

However, the above-mentioned carbon tool steel, cold tool steel, and martensitic stainless steel have insufficient hardness, and high-speed tool steel has a sufficiently high hardness but is expensive.

Further, in order to improve the sharpness of the blade, the blade is coated with abrasion-resistant TiN or the like. However, this coating is costly, and when the coating layer is peeled off or worn, it is easily coated. There is a drawback that the sharpness cannot be maintained for a long time because it cannot be repaired. In addition, the present inventors have developed a cladding material for a cutting tool in which an Al foil is sandwiched between stainless steels for a cutting tool and heated to generate an intermetallic compound of Fe and Al in a central portion, and applied for a patent ( Japanese Patent Application 7-2068
14), but the corrosion resistance was still insufficient for some applications.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a blade material having a high hardness at a cutting edge portion and excellent overall corrosion resistance, and a method for producing the same.

[0007]

In order to achieve the above object, the present invention provides a cutting tool material having excellent corrosion resistance, in which the both surfaces of the intermetallic compound of Ni and Al, such as NiAl and Ni ₃ Al, at the center are removed. That is, it was coated with a precipitation-hardened precipitation hardening Ni alloy.

In order to achieve the above object, in the method for producing a blade material having excellent corrosion resistance according to the present invention, an aluminum plate or an aluminum alloy plate is sandwiched between a precipitation hardening type nickel alloy plate and rolled and pressed. To produce an intermetallic compound of Ni and Al, and to precipitate and harden.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Precipitation-hardening Ni used in the present invention
The alloy is expressed by weight% (the same applies hereinafter), Be: 2%, balance Ni
Alloy consisting of: Be: 2%, Al: 3%, balance Ni
And the like. Further, the Al alloy used in the present invention is an Al alloy composed of 5% of Cu and the balance of Al.

In the present invention, a heating temperature for forming an intermetallic compound of Ni and Al and for precipitation hardening is 400 to 800 ° C., and a precipitation hardening type Ni alloy composed of 2% Be and the balance of Ni. 400 to 650
° C. The heating time depends on the thickness of Al, but is 100 to 300 minutes when Al is 0.05 mm. Further, the heating atmosphere may be in the air, but is preferably in an inert gas or in a vacuum.

[0011] The knife material of the present invention is a knife, a surgical knife,
It can be used for blades that require sharpness and corrosion resistance, such as cutting blades for salted salmon and salt trout.

[0012]

The blade material of the present invention having excellent corrosion resistance has a central part made of Al or an Al alloy and both surfaces of which are made of precipitation hardening Ni.
Since it is manufactured by coating with an alloy and reacting Al and Ni at the same time as precipitation hardening treatment to produce intermetallic compounds such as NiAl and Ni ₃ Al, a very hard layer is formed at the center, so the cutting edge Wear can be kept low. In addition, since the diffusion treatment is performed, a concentration gradient of Al is formed, and as a kind of graded material, the bonding force is high.
Peeling can be eliminated. Further, since the precipitation hardening type Ni alloy is used on both surfaces, not only the corrosion resistance is excellent, but also the hardness can be appropriately increased.

[0013]

Embodiments of the present invention will be described below. Example 1 Precipitation hardening type N composed of 2% Be and the balance of Ni
The i-alloy was melted and subjected to hot forging, hot rolling, cold rolling and bright annealing to prepare a 0.5 mm-thick plate. A 0.05 mm Al plate is sandwiched between the two plates thus manufactured,
A 1.0 mm three-layer clad material was prepared by cold rolling and pressure welding. This was heated in an inert gas at 550 ° C. for 130 minutes to produce an intermetallic compound of Ni and Al at the center to produce a blade material.

FIG. 1 shows the hardness distribution of the cross section of the blade material. FIG. 2 shows the rust generation rate of the blade material (Ni─Be / Al) after the salt spray test. Comparative material is SUS 4
20J2 martensitic stainless steel. The rust generation rate after the salt spray test was determined by the salt spray test method of JIS Z 2371, the amount of rust generated was measured by image processing, and calculated as a percentage of the entire area.

As shown in FIG. 1, the blade material of the present invention has a central portion having a high hardness of Hv650,
It turns out that it is suitable as a cutting edge of a cutting tool. FIG.
As shown in the above, the rust generation rate of the blade material of the present invention was 8%, which was about 4.8 of the comparative material SUS420J2.
It is one-half, and it can be seen that the corrosion resistance is particularly excellent.
Further, from FIGS. 1 and 2, the blade material of the present invention not only has excellent corrosion resistance on both sides but also has a high hardness (in the case of Ni alloy, Cr: 20%, and in the case of the remaining Ni alloy, the hardness is the same). Is about Hv280).

[0016]

According to the present invention, the above-described configuration enables
It has the following excellent effects. (1) Since the blade material of the present invention has a very hard layer at the center, the wear of the cutting edge can be suppressed low.
The sharpness can be kept long. (2) Further, since the blade material of the present invention is a Ni alloy with precipitation hardened on both sides, it has not only excellent corrosion resistance, but also has an appropriate hardness required for the blade. (3) Furthermore, the blade material of the present invention has a very hard layer at the center and has excellent corrosion resistance on both sides and a moderate hardness layer, so that good corrosion resistance and sharpness are required. It is suitable for use as a scalpel for surgery, cutting blades for salted salmon and salted trout, and the like.

[Brief description of the drawings]

FIG. 1 is a graph showing a hardness distribution of a blade material according to an example of the present invention.

FIG. 2 is a graph showing the corrosion resistance of a blade material according to an example of the present invention.

Claims (2)

[Claims] 1. A blade material excellent in corrosion resistance, characterized in that both surfaces of an intermetallic compound of Ni and Al at the center are coated with a precipitation hardening type Ni alloy. 2. Corrosion resistance characterized in that an Al plate or an Al alloy plate is rolled and pressed between precipitation hardening Ni alloy plates and then heated to produce an intermetallic compound of Ni and Al and precipitation hardened. Method of producing excellent blade material.