JP2896489B2 - Manufacturing method of titanium clad steel blade - 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 for manufacturing a titanium clad steel blade, and more particularly, to a method for improving the hardness of a cutting blade portion of a blade when performing quenching and hardening treatment. The present invention relates to a method for producing a titanium-clad steel cutting tool which does not cause deterioration or melt separation and has a good appearance of a clad boundary portion exposed on a blade cutting edge portion.

[0002]

2. Description of the Related Art At present, as a cutting tool which is designed to reduce weight and improve corrosion resistance while maintaining sharpness, a cladding in which a cutting blade portion made of stainless steel cutting steel is partially covered with a skin material made of pure titanium or a titanium alloy. A knife has been proposed (Japanese Utility Model Laid-Open No. 5-44056). If the blade other than the cutting edge is made of titanium material, which is excellent in light weight and corrosion resistance, not only can the weight of the whole blade be reduced and the corrosion resistance improved, but also the unique fertility caused by food contamination of iron-based ions can be reduced. It is possible to provide a high quality knife which is easy to use.

[0003] However, the titanium clad cutting tool described in Japanese Utility Model Laid-Open No. 5-44056 is manufactured by using a normal titanium clad steel plate in which stainless steel and a titanium alloy are simply directly clad and bonded. In fact, this titanium clad blade has an insufficient bonding strength between the cutting blade portion and the outer skin portion of the blade, so that there is a problem particularly in terms of durability.

[0004] That is, there is no problem when a normal titanium clad steel sheet is used as a building material. However, when the titanium clad steel sheet is used as a material for manufacturing a blade, the titanium clad steel has a high temperature. about
Various heat treatments such as quenching and hardening at 1050 ° C to 1070 ° C and cold rolling must be applied.These thermal histories have a negative effect on the quality of blades at the clad boundary between stainless steel and titanium alloy. As a result, unnecessary carbides and intermetallic compounds are inevitably generated, resulting in a decrease in the quality of the blade.

[0005] Specifically, as a result of the heat history of the quench hardening treatment, titanium carbide is generated at the cladding boundary, so that stainless steel is decarburized, and the quench hardening of the stainless steel is hindered, and the intended cutting edge Hardness is no longer obtained, and furthermore, at this cladding boundary, titanium and iron react to generate a low-melting intermetallic compound, and as a result, a large amount of hard and brittle intermetallic compound is generated during heat treatment. As a result, a situation in which the clad boundary is easily peeled off occurs.

That is, the above-mentioned Japanese Utility Model Laid-Open No. 5-44056 discloses that the outer shell of the blade is made of a titanium material, but does not disclose any specific means for realizing it. It is.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems in the conventional titanium clad blade, and has been developed in view of the temperature of stainless steel blade steel.
The technical object of the present invention is to provide a method for manufacturing a titanium clad steel cutting tool for a cutting tool which does not cause a decrease in bonding strength or melting and delamination at a clad boundary when subjected to various heat treatments such as quenching and hardening treatment at 1050 ° C to 1070 ° C. It is an issue.

Another technical object of the present invention is to provide a titanium-clad steel blade for a blade which is excellent in lightness and corrosion resistance, is durable, and has a good appearance of a clad boundary which can be exposed on a cutting edge. It is to provide a manufacturing method of.

[0009]

Therefore, according to the present invention, a blade steel 2 made of stainless steel blade steel is used as a cutting blade portion A of a blade, and a titanium base material 1 made of pure titanium or a titanium alloy is used as a shell material B of a blade. A method for manufacturing a titanium clad steel cutting tool, wherein a thin niobium layer 3 having a thickness of 0.38% of the total thickness is interposed between the titanium base material 1 and the blade steel material 2 on the titanium base material 1 side, A nickel thin layer 4 having a thickness of 0.19% with respect to the total thickness is interposed between the blade steel 2 and the superposed surfaces of the titanium base material 1, the niobium thin layer 3, the nickel thin layer 4 and the blade steel 2 are exposed to the outside air. By performing hot rolling while sealing and shutting off, and further performing cold finish rolling while performing intermediate annealing, the actual thickness of the intermediate intermediate layer formed by the niobium and nickel is in a range of 5 to 10 microns. Titanium clad steel plate From the obtained titanium clad steel sheet, a blade mold of a predetermined shape is shot out, a quenching and hardening treatment at a temperature of 1050 to 1070 ° C. is performed on the blade body mold, and a blade that has been subjected to the quench hardening treatment. The above-mentioned technical problem was successfully solved by adopting a method of grinding the mold and attaching the handle C to the base of the blade.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The specific structure of the present invention will be described below in more detail with reference to the embodiments shown in the accompanying drawings. 1 to 3 are schematic cross-sectional views showing a manufacturing process of a titanium clad steel for a cutting tool of the present embodiment, FIG. 4 is a schematic cross-sectional view showing a manufacturing process of a titanium clad steel cutting tool of the present embodiment, and FIG. It is a partial perspective view of a titanium clad steel blade of an embodiment.

In FIG. 1, what is indicated by reference numeral 1 is
Pure titanium material 20mm thick x 173mm wide x 223mm long (No.1
Species) are indicated by the reference numeral 2 and are indicated by stainless steel blade steel 12 mm thick x 115 mm wide x 155 mm long (0.8% carbon, 0.5% silicon or less, 0.3% manganese or less, phosphorus
0.03% or less, sulfur 0.03% or less, chromium 14%, molybdenum
The blade steel material consisting of 0.3%, the balance of iron), the one indicated by reference numeral 3 is a thin layer of niobium made of a niobium foil having a thickness of 0.2 mm × width 120 mm × length 160 mm, and the one indicated by reference numeral 4 is thickness It is a nickel thin layer made of nickel foil measuring 0.1 mm in width, 120 mm in width and 160 mm in length.

First, each of the above-mentioned materials was placed on a titanium base material 1, a niobium thin layer 3, a nickel thin layer 4, a blade steel material 2,
In the order of the nickel thin layer 4, the niobium thin layer 3, and the titanium base material 1,
Each superposed surface is cleaned and stacked, and the auxiliary materials 10 and 10 of the same quality as the titanium base material 1 are fitted to the side surfaces of the laminated body, and the seam between the auxiliary material 10 and the titanium base material 1 is formed over the entire circumference. By performing TIG welding 5, the superposed surface of each material is sealed off from the outside air (see FIG. 2). At this time, the total thickness of the sealed laminate is 52.6 mm, and the thickness 0.2 mm of the niobium thin layer 3 is equivalent to a thickness ratio of 0.38% to the total thickness 52.6 mm, and the thickness of the nickel thin layer 4 is 0.1 mm is the total thickness 52.6
This corresponds to a thickness ratio of 0.19% to mm.

Then, the above-mentioned sealed laminate is hot-rolled at about 850 ° C. to form a titanium-clad steel having a thickness of 4 mm × a width of 173 mm × a total length of about 2800 mm. Thereafter, the steel sheet is subjected to finish annealing in the cold while being subjected to intermediate annealing (temperature of about 800 ° C., time of 5 minutes) to obtain a clad steel sheet having a thickness of 2 mm (FIG. 3).
reference).

A knife-shaped blade mold is punched from the titanium clad steel sheet thus obtained, and the blade body is quenched and hardened (at a temperature of about 1050 ° C. to 1070 ° C. for 5 minutes).
By performing a grinding process (see FIG. 4) and attaching a handle C to the root of the blade, a blade is constituted by a cutting blade portion A formed by the blade steel material 2 and a skin portion B formed by the titanium base material 1. A knife (knife) is formed (see FIG. 5).

The titanium clad steel blade of the present embodiment has a thin niobium layer 3 between the titanium base material 1 and the blade steel material 2.
And the nickel thin layer 4 are interposed, so that the blade steel material 2
Even with the thermal history of quenching and hardening at a temperature of about 1050 ° C to 1070 ° C for stainless steel blade steel, secondary reactants that adversely affect blade quality are not generated at the cladding boundary, and high quality titanium Clad steel blades can be manufactured.

That is, in the titanium clad steel blade of the present embodiment, since the nickel thin layer 4 is interposed on the blade steel material 2 side,
The diffusion of carbon in the blade steel material 2 due to the heat history of the quench hardening treatment can be prevented, and decarburization of the blade steel material 2 that hinders quench hardening can be prevented. In addition, since the iron-nickel alloy formed at the boundary between the blade steel material 2 and the nickel thin layer 4 has excellent spreadability, the iron-nickel alloy may be cut off at the cladding boundary during cold rolling. Therefore, carbon diffusion of the blade steel material 2 can be reliably prevented without leakage. The melting point of this iron-nickel alloy is 14
Since the temperature is 50 ° C. or higher, there is no adverse effect that the clad boundary is peeled off during the quenching and hardening treatment at about 1050 ° C. to 1070 ° C.

The present inventor conducted a test using a copper alloy thin layer instead of the nickel thin layer 4 and an ultra-low carbon stainless steel foil instead of the niobium thin layer 3. In the process of manufacturing the steel material, the stainless steel foil was frequently constricted or broken, resulting in partial contact between the titanium base material 1 and the copper alloy thin layer. This contact portion was melted by the heat history of the quench hardening treatment, and as a result, carbon diffusion and decarburization of the blade steel material 2 were remarkable, and it was found that the blade steel material 2 could not be used as a clad steel material for cutting tools.

As described above, the diffusion of carbon during the quenching and hardening treatment can be reliably prevented by the nickel thin layer 4. However, when the nickel thin layer 4 reacts with the titanium of the titanium base material 1, about 1050 ° C. to 1070 ° C. This results in the formation of a titanium-nickel alloy having a melting point (about 955 ° C.) lower than the quenching and hardening treatment temperature of 0 ° C., which causes melt exfoliation during this quench hardening treatment. Therefore, in the present invention, the niobium thin layer 3 is interposed on the titanium base material 1 side. The use of the niobium thin layer 3 suppresses the generation of a reactant that adversely affects the quality of the blade with the nickel thin layer 4, and at the same time, the generation of a reactant that deteriorates the quality with the titanium base material 1. It is suppressing.

That is, the niobium thin layer 3 reacts with the nickel thin layer 4 to form a niobium-nickel intermetallic compound due to the heat history of the quenching and hardening treatment. This alloy has excellent spreadability and is cold rolled. There is no adverse effect such as breaking at the cladding boundary sometimes, and the melting point is about 1270 ° C. or higher, which is higher than the quench hardening treatment temperature, and there is no melting during the quench hardening treatment.

Moreover, this niobium is a metal which is very familiar with titanium of the titanium base material 1, and forms a solid solution between them. The niobium-titanium alloy formed between the niobium thin layer 3 and the titanium base material 1 also has excellent spreadability,
No breakage during cold rolling, and about 1660 ° C
Since it has the above high melting point, it does not peel off during quenching and hardening.

When only the thin niobium layer 3 is interposed between the titanium base material 1 and the blade steel material 2, the niobium of the niobium thin layer 3 reacts with the carbon of the blade steel material 2. Then, the decarburization phenomenon of the blade steel material 2 occurs, and the quenching and hardening is hindered. In the present invention, the niobium thin layer 3 could be adopted because the nickel thin layer 4 was interposed on the blade steel material 2 side.

When a test was conducted by using a thin tantalum layer instead of the thin niobium layer 3, the tantalum alloy layer was broken at the clad boundary during cold rolling, and was broken during the quench hardening treatment. It was found that the carbon diffusion phenomenon occurred in the part, and it could not be used as a clad steel material for cutting tools.

Further, when a test was conducted using a molybdenum thin layer instead of the niobium thin layer 3, the molybdenum alloy layer was broken during cold rolling similarly to the tantalum thin layer.
During the quenching and hardening treatment, it was found that a carbon diffusion phenomenon occurred in the broken portion, and it could not be used as a clad steel material for a cutting tool.

As described above, the present invention not only prevents the diffusion of carbon in the blade steel 2 due to the heat history of the quench hardening treatment, but also comprehensively considers the melting point temperature and spreadability of the compound formed between the materials. Has been developed. Since the ductility of the resulting compound during cold rolling is also taken into consideration, the niobium and nickel materials interposed between the titanium base material 1 and the blade steel material 2 can be thin, even when cold-rolled. Without shredding,
Thus, it is possible to reliably prevent the generation of a compound that causes a decrease in blade quality.

Therefore, as shown in FIGS. 4 and 5,
The apparent thickness T of the intermediate layer of niobium and nickel, which appears at the cladding boundary between the cutting edge portion A and the outer skin portion B of the titanium clad steel blade, is also extremely thin, and this intermediate layer has a good appearance of the blade. It doesn't hurt. In other words, this titanium clad steel blade is excellent in lightness and corrosion resistance, is also excellent in durability, and has a good appearance of the cutting edge portion A. 4 and 5, the apparent thickness T of the intervening intermediate layer is exaggerated, but the actual apparent thickness T is about 50 to 100 microns (true thickness: about 5 to 10 microns). ).

The embodiment, which is a specific example of the present invention, is generally configured as described above. However, the present invention is not limited to this embodiment, and various modifications may be made within the scope of the claims. Is possible.

For example, in the above embodiment, the titanium base material 1
Although a pure titanium material (first type) is used as the material, the present invention is not limited to this, and a titanium alloy of aluminum 6% -vanadium 4% -remaining titanium may be used. In addition, the blade steel material 2 is not limited to the above-described embodiment, but includes carbon 0.9% -silicon 0.5% or less-manganese 0.3% or less-phosphorus 0.03% or less-sulfur 0.03%
The following may be used: 15% chromium, 0.3% molybdenum, and stainless steel with the balance of iron.

[0028]

As described above in the embodiment, in the method for manufacturing a titanium clad steel blade according to the present invention, a niobium thin layer and a blade steel material side are provided between the titanium base material and the blade steel material on the titanium base material side. Temperature is about 1050 ° C ~ 1070 to improve the hardness of the cutting edge of the blade
When a quenching and hardening treatment at a temperature of ° C. is performed, a high-quality titanium clad steel for blades can be manufactured without causing a decrease in bonding strength or melting and delamination at the clad boundary.

Further, in the titanium clad steel cutting tool manufactured according to the present invention, the outer cladding material formed of titanium material is clad-joined to the cutting blade portion formed of stainless steel cutting steel via the intermediate layer of niobium and nickel. , While maintaining the sharpness as before, it is excellent in lightness and corrosion resistance, and also excellent in durability, and since the intermediate layer of niobium and nickel is extremely thin, this intermediate layer is It is possible to provide a high-quality titanium-clad steel blade without impairing the appearance.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing a manufacturing process of a titanium clad steel for manufacturing a cutting tool of the present embodiment.

FIG. 2 is a schematic sectional view showing a manufacturing process of the titanium clad steel according to the embodiment.

FIG. 3 is a schematic sectional view showing a manufacturing process of the titanium clad steel according to the embodiment.

FIG. 4 is a schematic cross-sectional view showing a manufacturing process of the titanium clad steel blade of the present embodiment.

FIG. 5 is a partial perspective view of the titanium clad steel blade of the present embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Titanium base material 2 Blade steel material 3 Niobium thin layer 4 Nickel thin layer A Cutting edge part B Skin part C Pattern

Claims (1)

(57) [Claims] 1. A method for manufacturing a titanium clad steel blade, wherein a blade steel 2 made of stainless steel blade steel is used as a cutting edge portion A of a blade, and a titanium base material 1 made of pure titanium or a titanium alloy is used as a shell material B of the blade. A thin niobium layer 3 having a thickness of 0.38% with respect to the total thickness is interposed between the titanium base material 1 and the blade steel material 2 on the titanium base material 1 side, and a thickness of 0.19% with respect to the total thickness. Of the titanium base material 1, the niobium thin layer 3, the nickel thin layer 4 and the blade steel material 2 are sealed off from the outside air and hot rolled. And cold finishing and rolling while further performing intermediate annealing to form an intermediate intermediate formed by the niobium and nickel.
A titanium clad steel sheet of a predetermined thickness having an actual thickness of the layer in the range of 5 to 10 microns is obtained, and a blade body of a predetermined shape is shot from the titanium clad steel sheet thus obtained, and a temperature is applied to the blade body. 1050 ~
A method of manufacturing a titanium-clad steel blade, comprising: performing a quench hardening treatment at 1070 ° C .; and grinding the blade body that has been subjected to the quench hardening treatment, and attaching a handle C to a root of the blade body.