JPH07100298B2 - Surface treatment method for metal work and method for manufacturing coated tool - Google Patents

Description

Detailed Description of the Invention [Industrial applications]

The present invention relates to a surface treatment method and a method of manufacturing a coated tool having a coating film with high hardness.

[Prior art]

In order to form a high-hardness coating such as cemented carbide or ceramics on the surface of industrial products such as tools and molds, it is necessary to clean the surface of the work before the coating treatment. Especially when the product is a cutting tool,
In order to cause grinding burn and burrs in the grinding process, as shown in FIGS. 5 (a), (b) and (c), a physical surface treatment such as sand blasting or liquid honing is applied to the coating. In many cases, these are removed by performing the pretreatment.

[Problems to be Solved by the Invention]

When sandblasting is used to remove grinding burns and burrs in the grinding process, the burns and burrs described above can be sufficiently removed, but the product surface after coating is matte, that is, the gloss is lost. It becomes a broken state. It is considered that this is because the polishing power of the polishing agent used in the conventional sandblasting treatment is too strong, so that the surface of the work is roughened. Therefore, when the product is a cutting tool such as an end mill or a drill and the cutting edge is sharp, the cutting edge may be damaged due to the excessively sharpening and cleaning force. Also, when the liquid honing treatment is adopted for the same purpose, the problem that the gloss disappears occurs similarly to the above sand blasting treatment, and in this case, the coating film may cause the adhesion failure. In the liquid honing treatment, it is necessary to add a rust preventive agent to the honing liquid in order to perform the rust preventive treatment, but it is considered that the rust preventive agent cannot be completely removed by the chemical cleaning in the next step. Thus, conventional sandblasting and liquid honing treatments lose the luster of the product and, if the product is a tool with sharp cutting edges, damage the cutting edges and, therefore, improve performance. There are various technical problems such as not being able to obtain a product. The present invention has been made in view of the above-mentioned conventional technical problems to effectively solve them. Therefore, the purpose is a method of surface treatment as a pre-process when coating a tool or a mold, and the adhesion state of the coating film formed by the coating treatment after the surface treatment is good, and the coating film is To devise a surface treatment method that does not lose gloss after coating treatment, and when the product is a cutting tool with a sharp cutting edge,
It is to create a surface treatment method capable of obtaining a high-performance cutting tool without affecting the cutting edge, etc., and to manufacture a high-performance cutting tool using the surface treatment method. .

[Means for Solving the Problems]

MEANS TO SOLVE THE PROBLEM The surface treatment method of the metal work and the manufacturing method of a coating tool which concern on this invention are comprised as follows in order to solve the conventional technical subject and to achieve the objective. That is, the metal work surface treatment method of the first invention is a blasting treatment method in which spherical glass particles having a particle size of 10 μm or more and 45 μm or less are sprayed onto the work surface by a dry method in order to clean the surface of the metal work. Also, the second
The method for manufacturing a coated tool according to the invention is a coated tool including a work surface treatment as a pre-process for coating a high hardness coating in its structural process, wherein the work surface treatment is a blasting treatment according to the first invention. Has been adopted.

[Action]

According to the surface treatment method for a metal workpiece according to the first aspect of the present invention, the surface of the workpiece can be appropriately ground and cleaned as a pretreatment for coating. That is, even if the metal work has a sharp portion like the cutting edge of a cutting tool, it can be ground and swept without damaging the sharp portion, and The surface can also be clean and smooth and can be coated. Further, according to the method for producing a coated tool according to the second aspect of the present invention, it is possible to obtain a coated tool having a surface with good adhesion of the coating even in the sharp portion of the cutting edge portion and maintaining gloss.
Therefore, the coated tool manufactured according to the present invention has high cutting performance and long tool life.

【Example】

A preferred embodiment of the present invention will be described below with reference to FIGS. 1 to 4. In this example, PV was used as the coating treatment.
A TiN (titanium nitride) coating was formed by D (physical vapor deposition) ion plating. FIG. 1 shows a process diagram when the surface treatment method according to the present invention is applied. In this example, instead of the conventional sand blasting treatment and liquid honing treatment, ultrafine glass bead blasting treatment in which glass particles having a particle diameter of 10 μm or more and 45 μm or less are used for the blasting treatment,
Various experiments were performed on the drill as a coated tool obtained by performing dry treatment on the drill as a surface treatment as a pre-process when applying the coating. In addition,
In the blast treatment of ultrafine glass beads according to the present invention, the glass particles used for the blasting treatment, that is, glass beads per drill, the pressure is 5 kg / cm ^{2, the} distance is 100 mm, and the treatment time is 30 seconds to 5 minutes. Under the pressure, a nozzle having a diameter of 3.2 mm was used to spray the work. Also, those not subjected to pretreatment equivalent to ultrafine glass bead blast treatment, those subjected to sand blast treatment,
Liquid honing processed, particle size 50μm or more 90μ
The coating treatment was also performed on each of the semi-fine glass bead blast treatments using spherical glass particles of m or less, and the same experiment was conducted on the resulting coated tools. The surface of the cutting tool which has been subjected to each of the above treatment methods as a pretreatment for coating, the one subjected to the ultrafine glass bead blast treatment according to the present invention is the closest to the surface state without pretreatment, specifically 10 μm or less. No blast marks appeared, and the gloss and surface roughness were not lost. It should be noted that the surface of the blasted semi-fine glass beads is 30 μm
The above blast marks appear and the gloss is dull. In addition, the sand blasted product was rough enough to lose the ground surface and had no gloss.In the liquid honing process, in addition to the results similar to the sand blasted process, adhesion of the rust preventive agent was observed. It was FIG. 2 is a graph showing the surface roughness of the drill margin portion which is pretreated by each method and the surface roughness of the drill margin portion which is not pretreated. It can be read that the surfaces of the finely beaded glass beads blasted according to the present invention shown in (a) and the surface without pretreatment shown in (b) are smooth because the polygonal lines have few variations. In addition, quasi-fine glass bead blast treatment shown in ((e),
The liquid honing treatment shown in (d) and the sand blasting treatment shown in (c) increase in variation in the polygonal line, and it is clear that the finished surface becomes rough in this order. Therefore, the effect of the blasting process on the work increases in this order, and the cutting edge is often damaged in cutting tools that have undergone such a blasting process, which leads to a decrease in performance. It will be. In FIG. 3, the film adhesion of the drill coated with the pretreatment by each method and the coating without the pretreatment was measured three times by the scratch test, and the results are shown in a bar graph. . The numerical value at the top of each graph is the average value of three measurements.
This indicates that the coating applied after the liquid honing treatment has the lowest adhesion. This is because the liquid honing treatment can sufficiently remove the grinding burn and the burr as described above, but has a problem that the rust preventive agent adheres and the rust preventive agent cannot be completely removed by the subsequent chemical cleaning. Next, the one with the smallest adhesion is
Without pretreatment. This is because the removal of burns, burrs and other impurities is incomplete. The sandblasted ones have the next weaker adhesion, due to the roughest finish surface tested. And quasi-fine glass bead blasting,
The order of ultrafine glass bead blasting was the order, and the highest value was obtained with the ultrafine glass bead blasting according to the present invention. This is because burning, burrs, and other impurities have been almost completely removed, and the finished surface has a good condition. Further, in FIG. 4, the cutting performance (number of drilling times) of each of the drill coated with pretreatment by each method and the coating coated without pretreatment was tested three times. The results are shown in a bar graph as in FIG. The numerical value at the top of each graph is the average value of three times. According to this graph, the pretreatment of the coating is liquid honing treatment, sand blasting treatment, no pretreatment, quasi-fine glass bead blasting treatment, and ultrafine glass bead blasting treatment according to the present invention. It is obvious that the glass beads that have been subjected to the glass bead blasting have outstandingly high performance, that is, they have excellent durability. In this test, using a JIS straight drill with a diameter of 6 mm under all the following conditions, 20
mm through. Cutting speed 30m / min 0.18mm / rev Material S50C (HB240-255) In this embodiment, the blasting process has a particle size of 10 μm.
Glass particles of 45 μm or less were used, but the material is not limited to glass, and it has the same polishing and cleaning force as glass, that is, the relative hardness to the work is almost equal to that of glass, and the particle size is May be 10 μm or more and 45 μm or less. Further, the coating treatment is not limited to the TiN coating by PVD ion plating in the present embodiment, and other coatings of substantially the same (super) hard material may be formed. Furthermore, it goes without saying that the surface treatment method according to the present invention can be applied not only to the manufacturing process of the coated tool but also to other industrial products such as molds as described in the section of the prior art.

【The invention's effect】

As is clear from the above description, according to the present invention, the following excellent effects are exhibited. That is, according to the surface treatment method of the present invention, the work surface is not unnecessarily ground and spoiled so as not to impair its surface roughness and is not damaged. It can also be applied to places that are easily damaged,
Moreover, the smoothness of the surface is sufficiently maintained and the luster remains. Also, even if it is subjected to a coating process afterwards, it maintains its luster,
A high hardness coating having good surface roughness and high adhesion can be formed. Further, when the product is a cutting tool, it is possible to obtain a cutting tool having high cutting performance and long life.

[Brief description of drawings]

FIG. 1 is a process diagram when the surface treatment method according to the present invention is applied as a pretreatment for coating, and FIG. 2 is a graph diagram showing the surface roughness of a drill margin portion which has been pretreated by various methods. FIG. 3 is a graph showing the adhesion of the coating film of a cutting tool which has been pretreated by various methods and then coated, and FIG. 4 is a graph showing the performance of a drill which has been pretreated by various methods and then coated. FIG. 5 is a process diagram when a conventional surface treatment method is applied as a pretreatment for coating.

Claims (2)

[Claims] 1. A surface treatment method for cleaning the surface of a metal work, which comprises spraying spherical glass particles having a particle size of 10 μm or more and 45 μm or less onto the surface of the work by a dry method. 2. A method of manufacturing a coated tool including a work surface treatment as a pre-process when coating a high hardness coating, wherein the work surface treatment is the surface treatment method according to claim 1. Manufacturing method of coated tool.