JP2021169108A - Hard metal member manufacturing method and hard metal member - Google Patents

Abstract

To provide a method that can efficiently and easily obtain a cladded layer of hard metal having excellent abrasion resistance and good finished surface, and a hard metal member that is manufactured by the method.SOLUTION: A hard metal member manufacturing method includes: a first step of forming a cladded layer of hard metal on a surface of a metal base material by laser powder cladding by welding, using mixed powder containing self-fluxing alloy powder and hard particles as raw materials; a second step of forming a cladded layer of metal on a surface of the cladded layer of hard metal by the laser powder cladding by welding, using only the self-fluxing alloy powder as raw materials; and a third step of applying cutting processing to the cladded layer of metal.SELECTED DRAWING: Figure 1

Description

The present invention relates to a method for manufacturing a hard metal member having a metal overlay layer on the surface of a metal base material, and a hard metal member obtained by the manufacturing method.

Conventionally, as one of the surface treatment techniques, a technique for improving the wear resistance of the outermost surface by overlaying a high hardness material different from the metal base material on the surface of the metal base material is known. When this technique is used, the base material can retain its original shape even if the build-up layer on the surface formed by using the high-hardness material is worn, so the same build-up is performed again on the base material. Therefore, it can be used repeatedly. For example, Patent Document 1 (Japanese Unexamined Patent Publication No. 2013-176778) discloses a laser cladding method for forming a high-hardness overlay layer on the surface of a metal substrate by using a laser as a method for overlaying. There is.

Further, in Patent Document 2 (Japanese Unexamined Patent Publication No. 4-371390), a wire that is shielded on an iron-based base material in a non-oxidizing atmosphere to form a matrix of desired components is welded and built up, and the matrix melting pool is formed. Cemented carbide granules with a particle size of 0.5 to 3.0 mm are added at a constant rate into the matrix, and a composite structure in which the cemented carbide granules occupying 30 to 70% by weight of the overlay layer is evenly dispersed in the matrix is formed. A method for welding an abrasion-resistant overlay layer, which is characterized by forming, is disclosed.

The welding machine used for overlay welding in Patent Document 2 emits an arc from the tip of a torch shielded with a non-oxidizing atmosphere, that is, a neutral (or reducing) gas to form a welded portion on a base metal. It is a model, so-called metal inert gas arc welder, and this type of welder is already widely used in each factory, and you can freely select any wire material and freely adopt any matrix. It is said that it has excellent versatility and workability, such as being able to travel to a mountain crushing site if necessary and perform overlay regeneration on site.

Japanese Unexamined Patent Publication No. 2013-176778 Japanese Unexamined Patent Publication No. 4-371390

By using the laser cladding method described in Patent Document 1 and the welding method of the wear-resistant overlay layer described in Patent Document 2, various metal overlay layers can be efficiently and easily formed on the surface of the base material. Can be formed. Further, for example, the size of a conventional general cemented carbide material is limited because it is manufactured by sintering, and when it is used as a tool or the like, brazing or mechanical joining to a base material is required. By forming a metal overlay layer on the surface of the metal base material, it becomes easy to manufacture a large product, and it is not necessary to bond the metal base material to the base material in a separate process. However, in order to obtain the final shape of the product, it is necessary to perform cutting or the like on the metal overlay layer.

Here, the metal overlay layer generally has a high hardness, and especially when the metal overlay layer contains hard ceramic particles, the difficulty of finishing is extremely high, and a special and expensive cutting tool is used. It cannot be processed without it. More specifically, for example, machining cannot be performed unless the machining speed is extremely reduced with a cutting tool made of CBN or a cutting tool made of a diamond sintered body is used. Therefore, an increase in manufacturing cost and processing time has been a big problem.

In view of the above problems in the prior art, an object of the present invention is a method for easily and efficiently obtaining a hard metal overlay layer having excellent wear resistance and a good finished surface, and the method for producing the same. The purpose is to provide a hard metal member.

As a result of diligent research on a method for forming and processing a hard metal overlay layer in order to achieve the above object, the present inventors have formed a hard metal using a mixed powder containing a self-soluble alloy powder and hard particles as a raw material. We have found that it is extremely effective to form a metal overlay layer on the surface of the metal overlay layer using only the self-soluble alloy powder as a raw material, and to perform a cutting process on the metal overlay layer. Reached.

That is, the present invention
The first step of forming a hard metal overlay layer on the surface of a metal substrate by laser powder overlay welding using a mixed powder containing self-soluble alloy powder and hard particles as a raw material.
A second step of forming a metal overlay layer on the surface of the hard metal overlay layer by the laser powder overlay welding using only the self-soluble alloy powder as a raw material.
Including a third step of cutting the metal overlay layer.
Provided is a method for manufacturing a hard metal member, which is characterized by the above.

In the method for manufacturing a hard metal member of the present invention, a metal overlay layer softer than a hard metal overlay layer containing hard particles is the main target of cutting, so that a good finished surface can be easily formed. Can be done. Further, in the process of forming the metal overlay layer, the vicinity of the surface of the hard metal overlay layer is slightly softened, so that the cutting process of the region becomes easy.

Here, since the self-soluble alloy powder, which is the raw material of the metal overlay, is also the raw material of the hard metal overlay, no impurity elements or the like are mixed in the hard metal overlay, and the hard metal overlay is not mixed. The impact on the layer can be minimized. The self-soluble alloy is an alloy composed of a nickel group or a cobalt group containing a flux component such as boron or silicon.

The type, shape, and size of the hard particles are not particularly limited as long as the effects of the present invention are not impaired, and various conventionally known ceramic particles can be used. The amount of hard particles added may be appropriately set according to the desired hardness and wear resistance of the hard metal overlay layer, but from the viewpoint of obtaining a good hard metal overlay layer without defects, 60 vol. .. % Or less is preferable.

Further, in the method for producing a hard metal member of the present invention, it is preferable that the hard particles are tungsten carbide (WC) particles. Tungsten carbide particles have high hardness and are also the main component of industrially used cemented carbide, and when combined with an appropriate self-soluble alloy powder, the hard metal overlay layer is comparable to cemented carbide. Abrasion resistance can be imparted.

Further, in the method for producing a hard metal member of the present invention, it is preferable that the hard particles are pulverized powder. In general, the pulverized powder guarantees the original mechanical properties of the material, and can surely impart high hardness to the hard metal member.

Further, as a self-soluble alloy which becomes a sintered phase of hard particles in a hard metal overlay layer, various conventionally known metals can be used as long as the effect of the present invention is not impaired, but cemented carbide and cermet can be used. The metal material used as the metal bonding phase of the above can be preferably used. The size and shape of the self-soluble alloy powder may be appropriately adjusted in consideration of the shape, size and addition amount of the hard particles so that a defect-free hard metal overlay layer is efficiently formed.

Further, it is preferable that the self-soluble alloy powder is a nickel-based self-soluble alloy powder. A typical metal bonding phase of a cemented carbide is a cobalt-based alloy or a nickel-based alloy, but by using a nickel-based alloy, excellent corrosion resistance and toughness can be imparted to the hard metal overlay layer.

Further, in the method for manufacturing a hard metal member of the present invention, it is preferable to perform a cutting process on the hard metal overlay layer. Only the metal overlay formed on the surface of the hard metal overlay may be cut to obtain the desired final shape, but in that case, a small amount of the metal overlay having poor hardness and abrasion resistance is present on the surface again. Will remain in. On the other hand, by cutting the vicinity of the surface of the hard metal overlay layer, a hard metal member having an extremely uniform outermost surface and high hardness can be obtained. Here, in the process of forming the metal overlay layer, the edges of the hard particles near the surface of the hard metal overlay layer are rounded and the size is reduced, so that the situation is suitable for precision cutting.

On the other hand, by performing the cutting process only on the metal overlay layer, the cutting process time is shortened and the cutting accuracy is improved. Further, when only the metal overlay layer is cut, the outermost surface of the hard metal member becomes the metal overlay layer, and since hard particles do not exist in the metal overlay layer, it is fine for lubrication and anti-slip. Pattern processing is also possible. Further, for example, a metal overlay layer and a hard metal overlay layer can be used properly in a portion that wears normally and a portion that wears heavily. Further, for the purpose of repair, overlay welding of a self-soluble alloy can be performed.

In the method for manufacturing a hard metal member of the present invention, since the hard metal overlay layer and the metal overlay layer are formed by laser powder overlay welding, there are basically no restrictions on the shape and size, and conventional sintering is performed. It is possible to obtain a large member that cannot be manufactured with a material.

In addition, the present invention
It has a hard metal overlay layer on the surface of the metal base material,
The hard metal overlay layer is composed of a self-soluble alloy and hard particles.
The average particle size of the hard particles on the outermost surface of the hard metal overlay layer is smaller than the value of the entire hard metal overlay layer.
A hard metal member, characterized by the above, is also provided.

The hard metal member of the present invention can be suitably obtained by the method for producing a hard metal member of the present invention, but the average particle size of the hard particles on the outermost surface of the hard metal overlay layer is the value of the entire hard metal overlay layer. By making it smaller than, a smooth and precise surface shape can be realized. The rounded edges of the hard particles also reduce the average particle size of the hard particles.

Further, in the hard metal member of the present invention, the hard particles are preferably tungsten carbide (WC) particles, and the hard particles are preferably pulverized powder. As described above, various conventionally known ceramic particles can be used as the hard particles, but the tungsten carbide particles have high hardness and excellent wear resistance, and by using the pulverized powder, the material is originally made. It is possible to fully express the properties of the particles.

Further, it is preferable that the hard metal member of the present invention has a region made of a metal overlay layer on the surface of the metal base material, and the metal overlay layer is made of the self-soluble alloy. For example, by forming the surface of a part of a hard metal member that wears normally as a metal overlay layer and the part that wears heavily as a hard metal overlay layer, it is possible to obtain a hard metal member in which wear progresses in a well-balanced manner as a whole. can.

Further, the hard metal member of the present invention is preferably any of a transfer roller, a mold and a cutting tool. Conveying rollers, dies and cutting tools are required to have a smooth and precisely machined surface shape and excellent wear resistance, and the hard metal member of the present invention meets all of these requirements.

According to the present invention, it is possible to provide a method for easily and efficiently obtaining a hard metal overlay layer having excellent wear resistance and a good finished surface, and a hard metal member manufactured by the method.

It is a process drawing of the manufacturing method of the hard metal member of this invention. It is a schematic diagram which shows the formation method of the hard metal overlay layer in this invention. It is a schematic diagram which shows an example of the laser scanning direction about the powder overlay welding in this invention. It is the schematic sectional drawing which shows an example of the hard metal overlay layer 6. It is a schematic cross-sectional view which shows the state of the material to be processed after the 1st process and after the 2nd process. It is a schematic cross-sectional view which shows one aspect of the hard metal member of this invention. It is a schematic cross-sectional view which shows another aspect of the hard metal member of this invention. It is a photograph which shows the state of the cutting process in an Example. It is a photograph which shows the surface state of the hard metal overlay layer which was cut in an Example.

Hereinafter, a method for manufacturing a hard metal member of the present invention and a typical embodiment of the hard metal member will be described in detail with reference to the drawings. However, the present invention is not limited to those shown in the drawings, and each drawing is for conceptually explaining the present invention. Therefore, the ratios and numbers are exaggerated or simplified as necessary for easy understanding. It may be expressed as a conversion. Further, in the following description, the same or corresponding parts may be designated by the same reference numerals, and duplicate description may be omitted.

1. 1. Manufacturing Method of Hard Metal Member FIG. 1 shows a process diagram of the manufacturing method of the hard metal member of the present invention. The method for producing a hard metal member of the present invention includes a first step (S01) of forming a hard metal overlay layer on the surface of a metal substrate by laser powder overlay welding and a hard metal overlay welding by laser powder overlay welding. It includes a second step (S02) of forming a metal overlay layer on the surface of the layer and a third step (S03) of performing a cutting process on the metal overlay layer. Hereinafter, each of these steps will be described in detail.

(1) First step (S01: Formation of hard metal overlay layer)
The first step is a step for forming a hard metal overlay layer on the surface of a metal base material by laser powder overlay welding using a mixed powder containing a self-soluble alloy powder and hard particles as a raw material.

FIG. 2 shows a schematic view of a method for forming a hard metal overlay layer according to the present embodiment. In the method for forming a hard metal overlay layer according to the present embodiment, laser powder overlay welding is used. Here, laser powder overlay welding is also called a laser metal deposition method, which is substantially the same as, for example, a laser cladding method or a direct energy deposition method. By melting a raw material powder using a laser beam 2, the raw material powder is melted. The hard metal overlay layer 6 can be formed in the overlay region of the metal substrate 4.

In laser powder overlay welding, the metal powder is melted by condensing the laser beam 2 emitted from the laser light source and applying local heat, so that the hard metal overlay layer 6 is rapidly melted and rapidly cooled and solidified. Is formed by. Further, it is possible to reduce the heat strain and the heat-affected zone on the metal base material 4 and reduce the dilution ratio between the metal base material 4 and the formed hard metal overlay layer 6. Further, the laser beam 2 and the torch portion 8 for ejecting the raw material powder can be robot-controlled by a program, and the formation region and shape of the hard metal overlay layer 6 can be controlled relatively accurately.

FIG. 3 shows a schematic view showing an example of the laser scanning direction in powder overlay welding. In laser powder overlay welding, it is basic to form a substantially planar hard metal overlay layer 6 by linear movement of the laser beam 2 and parallel movement at predetermined intervals with respect to a desired overlay region.

FIG. 4 shows a cross-sectional view of the hard metal overlay layer 6. As shown in FIG. 4, when adjusting the dimensions of the hard metal overlay layer 6 to be formed in the thickness direction, it is desirable to have a laminated structure composed of a plurality of weld beads. As a more specific laminating method, the method for manufacturing a tool material disclosed in Japanese Patent Application Laid-Open No. 2016-155155 can be used.

The conditions for laser powder overlay welding used to form the hard metal overlay layer 6 include laser output, laser focal distance, laser scanning speed, raw material powder supply amount, carrier gas (shield gas) supply amount, and longitudinal length. Regarding the amount of parallel movement in the direction Y and the like, it is preferable to appropriately select the optimum conditions according to the composition, shape, size, mixing amount and the like of the metal base material 4, the self-soluble metal powder and the hard particles to be used.

The material of the metal base material 4 is not particularly limited as long as the effects of the present invention are not impaired, and various conventionally known metal materials can be used. As the metal material, for example, various stainless steels, alloy tool steels, iron-based alloys such as high-speed tool steels, nickel-based alloys, and cobalt-based alloys can be used.

The hard particles used as a raw material are not particularly limited as long as the effects of the present invention are not impaired, and various conventionally known ceramic particles can be used. Examples of the ceramic particles include carbides such as WC, TiC, VC, Mo ₂ C, ZrC, HfC, NbC, TaC, Cr ₃ C ₂ , SiC, and nitrides such as Si ₃ N ₄ , and borides such as TiB _2. And _{oxides such as Al 2} O ₃ can be exemplified, but WC is preferable. By using WC as the hard particles, it is possible to impart wear resistance equal to or higher than that of the sintered cemented carbide material to the hard metal overlay layer 6.

The composition, shape, and size of the hard particles can be appropriately selected, and may be appropriately selected according to the desired hardness, wear resistance, and the like with respect to the hard metal overlay layer 6.

Further, the self-soluble alloy powder is not particularly limited as long as the effect of the present invention is not impaired, and various conventionally known self-soluble alloy powders can be used, but nickel-based or cobalt-based self-soluble alloy powders can be used. It is preferable to use it. By using these, excellent corrosion resistance and toughness can be imparted to the hard metal overlay layer 6.

(2) Second step (S02: Formation of metal overlay layer)
In the second step (S02), only the self-soluble alloy powder used in the first step (S01) is used as a raw material, and a metal overlay layer is formed on the surface of the hard metal overlay layer 6 by laser powder overlay welding. This is the process of.

The conditions for laser powder overlay welding are not particularly limited as long as the effects of the present invention are not impaired, and appropriate adjustments may be made according to the type of raw material powder, the desired thickness of the metal overlay layer, and the like. Basically, a good metal overlay layer can be obtained by making fine adjustments as necessary based on the laser powder overlay conditions used in the first step (S01).

FIG. 5 is an example of the state after the first step and after the second step, and is a schematic cross-sectional view of the metal base material 4 and its surface. In the method for producing a hard metal member of the present invention, the hard metal overlay layer 6 may be formed on the raw metal base material 4, and the metal overlay layer 10 may be formed on the surface of the hard metal overlay layer 6. However, in consideration of the cutting process in the third step (S03), as shown in FIG. 5, the surface of the metal base material 4 is processed so that the hard metal overlay layer 6 becomes a resurface surface after the cutting process. Is preferable.

Specifically, a state in which a recess is formed on the surface of the metal base material 4, a hard metal overlay layer 6 and a metal overlay layer 10 are formed in the region, and the metal overlay layer 10 is cut off is defined as a finished shape. It is preferable to do so. By performing such a manufacturing process, it is possible to obtain a hard metal member having a hard metal overlay layer 6 as a resurface very efficiently easily and with high accuracy.

(3) Third process (S03: cutting)
The third step (S03) is a step of cutting the metal overlay layer 10 (hard metal overlay layer 6 if necessary) to obtain a hard metal member having a desired shape.

For example, when cutting a conventional hard metal overlay layer composed of WC particles and nickel-based self-soluble alloy powder, the hard metal overlay layer 6 has a hardness equal to or higher than that of a sintered cemented carbide material and wear resistance. Since it has properties, it is necessary to use a cutting tool made of CBN to extremely slow down the processing speed, or to use a cutting tool made of an expensive diamond sintered body. On the other hand, in the third step (S03), since the metal overlay layer 10 is mainly machined, it can be machined at a relatively high speed by using a general-purpose inexpensive cutting tool.

Further, when cutting is performed only on the metal overlay layer 10, since hard particles do not exist in the metal overlay layer 10, for example, it is possible to process a fine pattern for the purpose of lubrication and anti-slip.

Further, the edge of the hard particles near the surface of the hard metal overlay layer 6 is rounded by the heat input in the second step (S02), and the size is also reduced, so that the situation is suitable for precision cutting. There is. As a result, an extremely good finished surface can be obtained by slightly cutting the hard metal overlay layer 6.

2. Hard Metal Member FIG. 6 shows a schematic cross-sectional view of one aspect of the hard metal member of the present invention. FIG. 6 shows a case where the hard metal overlay layer 6 is formed on the entire surface of the metal base material 4. The hard metal overlay layer 6 is composed of a self-soluble alloy and hard particles, and the average particle size of the hard particles on the outermost surface of the hard metal overlay layer 6 is smaller than the value of the entire hard metal overlay layer 6.

In FIG. 6, the hard metal member 20 has a hard metal overlay layer 6 over the entire surface of the metal base material 4. Here, the surface shape of the hard metal member 20 is obtained by cutting and removing the metal overlay layer 10 formed on the surface of the hard metal overlay layer 6, and is obtained on the surface of the hard metal overlay layer 6. The thin metal overlay layer 10 may remain, and the metal overlay layer 10 may be completely removed. The metal overlay layer 10 is made of only the self-soluble alloy of the hard metal overlay layer 6.

When the metal overlay layer 10 formed on the surface of the hard metal overlay layer 6 is completely removed, the outermost surface of the hard metal member 20 becomes the hard metal overlay layer 6. Here, in the vicinity of the surface of the hard metal overlay layer 6, the hard particles are finer and have rounded corners as compared with other regions, so that the surface is smooth and has high dimensional accuracy. There is.

The average particle size of the hard particles on the outermost surface of the hard metal overlay layer 6 is smaller than the value of the entire hard metal overlay layer 6. The method for measuring the average particle size of the hard particles is not particularly limited, but for example, the particles are observed by observing an appropriate cross-sectional sample with an optical microscope or a scanning electron microscope, and using an observation image containing at least about 20 hard particles. The average value of the diameters may be calculated.

The hard particles of the hard metal overlay layer 6 are not particularly limited as long as the effects of the present invention are not impaired, and various conventionally known hard particles can be used. Examples of the ceramic particles include carbides such as WC, TiC, VC, Mo ₂ C, ZrC, HfC, NbC, TaC, Cr ₃ C ₂ , SiC, and nitrides such as Si ₃ N ₄ , and borides such as TiB _2. And _{oxides such as Al 2} O ₃ can be exemplified, but WC is preferable. By using WC as the hard particles, it is possible to impart wear resistance equal to or higher than that of the sintered cemented carbide material to the hard metal overlay layer 6. Further, the composition, shape and size of the hard particles can be appropriately selected, and may be appropriately selected according to the desired hardness and wear resistance of the hard metal overlay layer 6.

The self-soluble alloy powder of the hard metal overlay layer 6 is not particularly limited as long as the effect of the present invention is not impaired, and various conventionally known self-soluble alloy powders can be used. It is preferable to use it. By using a nickel-based alloy, excellent corrosion resistance and toughness can be imparted to the hard metal overlay layer 6.

The hard metal overlay layer 6 is metallurgically bonded to the metal base material 4. On the other hand, the mixing and dilution of the hard metal overlay layer 6 and the metal base material 4 are kept to a minimum, and the decrease in strength and the decrease in corrosion resistance in the vicinity of the bonding interface are effectively suppressed. Further, since the hard metal overlay layer 6 and the metal base material 4 are securely joined by metallurgy, it is suitable for applications in which a large stress or repeated stress is applied to the hard metal overlay layer 6. Can be used.

The metal base material 4 is not particularly limited as long as the effect of the present invention is not impaired, and various conventionally known metal base materials can be used, but the hard metal overlay layer 6 and / or the metal overlay formed on the surface is used. From the viewpoint of adhesion to the layer 10, mechanical properties, price, etc., it is preferable to use a steel material, and for example, tool steel, bearing steel, or the like can be preferably used. More specifically, as the metal base material 4, for example, a medium carbon steel material (S45C or the like), a chrome molybdenum steel material, an alloy tool steel material, a high carbon chrome bearing steel material, a stainless steel material or the like can be used.

FIG. 7 shows a schematic cross-sectional view of another aspect of the hard metal member of the present invention. FIG. 7 shows a case where a region of the hard metal overlay layer 6 and a region of the metal overlay layer 10 are formed on the surface of the metal base material.

In the hard metal member 20 shown in FIG. 7, the surface of the portion to be worn as standard is the metal overlay layer 10, and the portion to be heavily worn is the hard metal overlay layer 6, so that the wear progresses in a well-balanced manner as a whole. Can be done.

Here, the metal overlay layer 10 and the metal base material 4 are also metallurgically joined. Mixing and dilution of the hard metal overlay layer 10 and the metal base material 4 are kept to a minimum, and a decrease in strength and a decrease in corrosion resistance in the vicinity of the bonding interface are effectively suppressed.

The hard metal member 20 can be suitably used for any one of a transport roller, a mold and a cutting tool. Conveying rollers, dies and cutting tools are required to have a smooth and precisely machined surface shape and excellent wear resistance, and the hard metal member 20 meets all of these requirements. In addition, the hard metal overlay layer 6 and the metal overlay layer 10 can be formed by laser powder overlay welding, and the size of the hard metal member 20 is not particularly limited. Therefore, the conventional HIP (hot isostatic pressing) is used. It can be suitably applied to applications where the size is too large by the manufacturing method by the pressure pressing method) or the like, or to a large product which is not economically viable.

Hereinafter, the method for producing a hard metal member and the hard metal member of the present invention will be further described in Examples, but the present invention is not limited to these Examples.

Ni-based self-soluble alloy (NiBSi) powder and WC powder, WC powder is 30 vol. The mixture was mixed so as to be%, and laser cladding was applied on a cylindrical SS substrate having an outer diameter of 320 mm and a length of 2300 mm to form a two-layer hard metal overlay layer. Then, a thin metal overlay was formed on the surface of the hard metal overlay using only Ni-based self-soluble alloy (NiBSi) powder. A semiconductor laser was used as the laser, and the laser output was 5 kW, the laser beam width was 19 mm, and the laser moving speed was 900 mm / min.

Next, using a cutting tip made of CBN, the outer peripheral surface was cut under the conditions of the rotation speed of the work material: 40 rpm, the cutting feed: 0.25 mm / rev, and the depth of cut: 0.2 mm. The cutting situation is shown in FIG. 8, and an enlarged photograph of the cutting surface is shown in FIG. The cut surface is in a smooth state, and it can be seen that the hard metal member of the present invention can be surface-treated by general cutting. Further, the obtained surface is in a state where it can be used for various transport rollers and dies, and also contains a large amount of WC powder, and is excellent in abrasion resistance and the like.

2 ... Laser beam,
4 ... Metal substrate,
6 ... Hard metal overlay,
8 ... Torch section,
10 ... Metal overlay,
20 ... Hard metal member.

Claims (10)

The first step of forming a hard metal overlay layer on the surface of a metal substrate by laser powder overlay welding using a mixed powder containing self-soluble alloy powder and hard particles as a raw material.
A second step of forming a metal overlay layer on the surface of the hard metal overlay layer by the laser powder overlay welding using only the self-soluble alloy powder as a raw material.
Including a third step of cutting the metal overlay layer.
A method for manufacturing a hard metal member. The hard particles are tungsten carbide (WC) particles.
The method for manufacturing a hard metal member according to claim 1. That the hard particles are crushed powder,
The method for manufacturing a hard metal member according to claim 1 or 2. The self-soluble alloy powder is a nickel-based self-soluble alloy powder.
The method for manufacturing a hard metal member according to any one of claims 1 to 3. Cutting the hard metal overlay layer,
The method for manufacturing a hard metal member according to any one of claims 1 to 4. It has a hard metal overlay layer on the surface of the metal base material,
The hard metal overlay layer is composed of a self-soluble alloy and hard particles.
The average particle size of the hard particles on the outermost surface of the hard metal overlay layer is smaller than the value of the entire hard metal overlay layer.
A hard metal member characterized by. The hard particles are tungsten carbide (WC) particles.
The self-soluble alloy is a nickel-based self-soluble alloy.
The hard metal member according to claim 6. That the hard particles are crushed powder,
The hard metal member according to claim 6 or 7. The surface of the metal base material has a region composed of a metal overlay layer, and has a region.
The metal overlay layer shall be made of the self-soluble alloy.
The hard metal member according to any one of claims 6 to 8. Being one of a conveyor roller, a mold and a cutting tool,
The hard metal member according to any one of claims 6 to 9.

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