JP2002361443A - Method of manufacturing knife cutter material, knife cutter material and knife cutter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a knife cutter material to be made into a knife cutter having a hard edge and toughness as a whole, to eliminate the early wear of the edge and to maintain the cutting quality by which a good cutting surface or slicing surface is obtained. SOLUTION: A billet B constituted by disposing boundary materials 2 and 2 which are intermediate metallic layers on both sides of a base metal 1 of a steel sheet which is a central steel layer and disposing cladding metals 3 and 3 of steel sheets which are outer steel layers on both sides of the boundary materials 2 and 2. Next, the billet B is then forged or hot rolled, by which the base metal l, the boundary materials 2 and 2 and the cladding metals 3 and 3 are joined and the knife cutter material consisting of a five-layered structure arranged with the outer steel layers held with the intermediate metallic layers on both sides of the central steel layer is manufactured. The diffusion of carbon from the base metal to the cladding metals can be prevented in forging or hot rolling by using niobium(Nb) or tantalum(Ta) as the boundary materials.

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 material used for a machine for cutting or cutting hard resin such as FRP, reinforced plastic, wood, and the like, a blade material, and a blade.

[0002]

2. Description of the Related Art Generally, a material used for a knife is SK.
5, tool steel such as SKS51, high-speed tool steel such as SKH51, and stainless steel such as SUS420J2 and SUS440C. These materials are formed into a plate-like shape by hot rolling and cold rolling, formed into a blade material by die-cutting and the like, and further obtained through shaping, quenching, tempering, grinding, and cutting to obtain a desired blade. .

[0003]

However, with the recent increase in cutting speed of a cutting machine, the above-mentioned conventional blade material has a problem.
Due to early wear, it has become difficult to maintain sharpness and processing accuracy for a long time. Therefore, it is necessary to replace the blade frequently or grind the blade edge, and the workability is poor,
In addition, there is a problem that the cut surface is deteriorated, and the incidence of defective quality is increased.

In order to solve the above-mentioned problems, the present inventor has proposed that a high carbon steel material be used as a base material and a carbon material be used as a base material in order to obtain a blade material having a hard cutting edge and toughness on both sides. A blade material consisting of a clad material having a three-layer structure joined by using a steel material having a low content was experimentally manufactured. However, the prototype blade material was not satisfactory in the hardness of the cutting edge. Therefore, when investigating the cause, it was found that carbon in the base material was diffused and infiltrated into the composite material during joining by forging or hot working, and the present invention was completed. is there.

According to the present invention, a cutting material having a hard cutting edge and a tough cutting blade as a whole is easily manufactured, the premature wear of the cutting edge is eliminated, and the sharpness of obtaining a good cut surface or a cut surface is improved for a long time. The task is to maintain it.

[0006]

According to the present invention, there is provided a method for manufacturing a blade material, comprising a base material made of a carbon steel plate or a stainless steel plate and a boundary material made of a metal for preventing diffusion and penetration of carbon in the base material. Then, after arranging a composite material made of a carbon steel sheet or a stainless steel sheet having a smaller amount of carbon than the above-mentioned base material, it is subjected to forging or hot rolling to be joined. When the final thickness of the blade material is small to some extent (for example, several mm or less), a cold rolling step may be performed after forging or hot rolling.

According to this means, during forging or hot rolling, the boundary material acts as a so-called barrier that prevents diffusion of carbon from the base material to the composite material, and forms a layer that does not form a solid solution of carbon C. Become. Therefore, a five-layered blade material having a clear difference in carbon content between the central portion and the outer portions on both sides thereof can be easily obtained.

[0008] The blade material of the present invention has a five-layer structure of a central steel layer, an intermediate metal layer disposed on both sides of the central steel layer, and an outer steel layer disposed on both sides of the intermediate metal layer. And the carbon content of the outer steel layer has a relationship of center steel layer> outer steel layer, and the intermediate metal layer is insoluble in carbon.

[0009] When using this blade material, a sufficiently high hardness is imparted to the central steel layer with the intermediate metal layer as a boundary surface by the subsequent quenching and tempering treatment. Therefore, a blade having a hard edge and having toughness as a whole and capable of maintaining good sharpness for a long period of time can be obtained. During quenching and tempering, the intermediate metal layer functions as a so-called barrier that prevents diffusion of carbon from the central steel layer to the outer steel layer.

In the present invention, the difference in carbon content (% by weight) between the central steel layer and the outer steel layer is 0.20 to 0.8 in weight%.
Preferably it is 0%. This is because, if this difference is smaller than 0.20%, it will be difficult for the blade (cutting edge) to exhibit a good wear state as described later.
On the other hand, if this difference exceeds 0.80%, the outer steel layer becomes too soft, and the strength as a whole tends to be insufficient.

In this case, the central steel layer is preferably made of high carbon steel or high carbon stainless steel, and the outer steel layer is preferably made of carbon steel or stainless steel having a lower carbon content than the central steel. is there. In addition, high carbon means that the carbon content is 0.5% by weight or more.

Further, it is preferable to use either niobium (Nb) or tantalum (Ta) for the intermediate metal layer.
In addition to this, there are metals insoluble in carbon, but they are inferior in cold workability or expensive, and are not practically suitable.

The blade of the present invention can be obtained by shaping, quenching, tempering and sharpening the cutting edge of the above blade material into a required shape.

With this blade, the edge is hard and the peripheral portion is softer than the edge, so that the peripheral portion is worn first during cutting or cutting. Therefore, the cutting edge is always slightly protruded, and the state of the sharp cutting edge is maintained for a long time.

In this case, the Vickers hardness of the central steel layer as the cutting edge is in the range of Hv 650 to 800, and the Vickers hardness of the outer steel layer as the peripheral portion of the cutting edge is Hv 400 to 55.
It is preferably in the range of 0. This is because if the hardness of the central steel layer is less than Hv650, the abrasion resistance tends to be insufficient, and if it exceeds Hv800, it becomes brittle, the blade is easily chipped, and trouble tends to occur during work. It is. Further, when the hardness of the outer steel layer is less than Hv400, the strength and vibration resistance (chatter resistance) as a whole tend to be insufficient, and when it exceeds Hv550, the toughness tends to decrease.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a billet B serving as a blade material. In the billet B, boundary materials 2 and 2 serving as intermediate metal layers are arranged on both sides of a base material 1 of a steel plate serving as a central steel layer. On both sides, laminated materials 3 and 3 of steel plates to be outer steel layers are arranged. Next, using the billet B, hot rolling-descaling-cold rolling-annealing is performed to obtain the base material 1 and the boundary materials 2 and 2.
And the joining materials 3 and 3 are joined to produce a blade material having a five-layer structure in which an outer steel layer is disposed on both sides of a central steel layer with an intermediate metal layer interposed therebetween.

In this case, as the steel plate of the base material 1, for example, a high carbon steel material such as S50C, SWRS92B, etc.
High carbon stainless steel materials such as SUS440A and SUS440C can be used. Further, as the steel plate of the composite material 3, for example, a carbon steel material such as S15CK and SWRS62A, and a stainless steel material such as SUS420J2 and SUS431 can be used. Further, as the metal plate of the boundary material 2, the carbon of the base material 1 is mixed with the bonding material 3 in the heat treatment.
Any metal can be used as long as it prevents diffusion and infiltration into N3. Considering workability and cost, Nb and Ta are preferable.

The boundary material is preferably in the form of a thin film or sheet as thin as possible, and its thickness is preferably controlled to 5 μm or less at the end of forging or hot rolling. This is because Ta or Nb used as the boundary material has a low strength, and if it exceeds 5 μm, the strength of the entire blade material tends to decrease.

FIG. 2 is a schematic enlarged cross-sectional view of the tip portion of the blade CT. The blade CT is obtained by cutting, cutting or cutting the above-mentioned blade material, followed by shaping, quenching, tempering, and sharpening of the cutting edge. It is. The blade CT has a Vickers hardness Hv 400 to 550 on both sides of a central steel layer 11 having a Vickers hardness Hv 650 to 800 via intermediate metal layers 12 and 12.
Has a five-layer structure in which outer steel layers 13 are arranged.

FIG. 3 is an enlarged explanatory view of the blade showing a worn state of the blade. The above tool CT is mounted on a machine and wood or FR
When the work material such as P is ground, the wear of the outer steel layer 12 having a low hardness advances before the center steel layer 11, and the tip P of the cutting edge is projected. Therefore, the sharpness of the blade is maintained for a long time, and the frequency of re-polishing of the blade is significantly reduced.

Incidentally, the material, combination and thickness of the steel plates serving as the central steel layer and the outer steel layer, the hardness difference between the central steel layer and the outer steel layer, the shape of the cutting edge, the contact angle with the work material, and the like are appropriately determined. By changing it, the above-mentioned favorable wear condition of the cutting edge can be exhibited.

[0022]

Example: Billet B Base material: 1 mm thick steel plate (SUS440A) Boundary material: 0.1 mm thick Ta film Combination material: 50 mm thick steel plate (SUS420J2) Billet thickness T: 100 mm or more After hot rolling-descaling,
Cold rolling and annealing were repeated to produce a blade material having a thickness of 1 mm. After cutting off the blade material, the blade was formed into a required shape, quenched, tempered, and polished to obtain a blade having a thickness t = 1 mm, a width of 50 mm, and a length of 30 mm. At this time,
The thickness of the central steel layer was 10 μm, and the thickness of the intermediate metal layer was 1 μm.

Next, a cutting tool was manufactured using a three-layered cutting tool manufactured in the same manner without using a boundary material, and a comparative example was obtained. FIG. 4 shows the results of measuring the hardness distribution from the center of the blades of the above-described example and the comparative example. As is clear from FIG. 4, the cutting edge of the comparative example has a hardness of Hv6.
Only about 00 was obtained, and the overall hardness was a relatively gentle slope from the central steel layer toward the outer steel layer.
On the other hand, in the cutting tool of the embodiment, the hardness of the cutting edge is Hv75.
0, the hardness of the outer steel layer at the boundary of the intermediate metal layer is Hv500.
The strength was kept almost constant.

Further, when the cutting tools of the example and the comparative example were mounted on a cutting tester to cut wood and FRP, the wear rate of the cutting edge of the cutting tool of the example was one time lower than that of the cutting tool of the comparative example.
/ 7 to 1/10.

[0025]

According to the method of the present invention, it is possible to easily produce a five-layer blade material having a clear difference in carbon content between the central portion and the outer portions on both sides thereof. Further, when using the blade material of the present invention, the hardness of the central steel layer serving as the cutting edge can be set high and the hardness of the outer steel layer can be set low with the intermediate metal layer as the boundary surface, and the cutting edge is hard and the toughness as a whole is improved. And a blade that can maintain good sharpness for a long period of time can be obtained. Furthermore, when using the cutting tool of the present invention, since the cutting edge is hard and its peripheral portion is soft,
In cutting or cutting, the peripheral portion is worn first, and the cutting edge is always in a slightly protruding state. Therefore, it is possible to always maintain a sharp cutting edge, to obtain a high-precision cutting surface or cutting surface, and to significantly reduce the frequency of re-grinding of the cutting edge and the frequency of replacing the cutting tool, thereby improving workability. It can be greatly improved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a billet serving as a blade material according to the present invention.

FIG. 2 is a schematic enlarged cross-sectional view showing a tip portion of the blade of the present invention.

FIG. 3 is an enlarged explanatory view of a cutting tool showing a worn state of a cutting edge.

FIG. 4 is a graph showing the hardness distribution from the center of the blade of the example and the comparative example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base material 2 Boundary material 3 Laminated material 11 Center steel layer 12 Intermediate metal layer 13 Outer steel layer B Billet CT Cutting tool

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B23K 103: 04 B23K 103: 04 F-term (Reference) 3C061 BA00 BA18 BA20 DD06 EE08 EE27 EE28 4E067 AA02 AA03 AB01 AC00 AD03 BD01 DA17 DD02 EB00 EC04 4F100 AA37A AA37B AA37C AA37D AA37E AA37H AB01B AB01C AB03A AB03D AB03E AB04A AB04D AB04E AB40B AB40C BA05 BA10D BA10E BA13 BA27 EC032 EC052 EJ162 Y12J20Y12J12Y00 J12Y20J12Y00J12Y20J12Y00J12Y20J12Y20J12Y12K

Claims (7)

[Claims] 1. A carbon steel sheet or a stainless steel sheet having a smaller amount of carbon than the above-mentioned base material, via a boundary material made of a metal for preventing diffusion and penetration of carbon in the base material on both sides of the base material made of a carbon steel sheet or a stainless steel sheet. After arranging the composite material made of steel sheet,
A method for producing a blade material, comprising joining by forging or hot rolling. 2. A five-layer structure comprising a central steel layer, an intermediate metal layer disposed on both sides of the central steel layer, and outer steel layers disposed on both sides of the intermediate metal layer. A blade material wherein the carbon content has a relationship of center steel layer> outer steel layer, and the intermediate metal layer is insoluble in carbon. 3. The blade material according to claim 2, wherein the difference in carbon content between the central steel layer and the outer steel layer is in the range of 0.20 to 0.80% by weight. 4. The blade material according to claim 2, wherein the central steel layer is made of high carbon steel or high carbon stainless steel, and the outer steel layer is made of carbon steel or stainless steel. 5. An intermediate metal layer comprising niobium Nb or tantalum T
The blade material according to claim 2, which is a. 6. A blade made of the blade material according to claim 2. 7. The Vickers hardness of the central steel layer is Hv650.
８００800, and the Vickers hardness of the outer steel layer is Hv400.
The cutting tool according to claim 6, wherein