JPH11198046A - Manufacture of cubic boron nitride polishing tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce liquid phase sintering brazing required temperature and time by adding specific metal as a metallic material for brazing. SOLUTION: At least two metals are selected from a group consisting of the metals of chrome, titanium, tin, nickel, tungsten, iron and cobalt and they are added to a powder alloy for welding with copper as its base material. Additionally, a water soluble high polymer substance is added with water to the brazing metal material as a binder. Hereby, weight ratios of metal elements are made; 0.005-0.05 for chrome, 0.005-0.20 for titanium, 0.000001-0.20 for tin, 0.000001-0.005 for nickel, 0.000001-0.005 for tungsten, 0-0.005 for iron and 0.000001-0.005 for cobalt.

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 cubic boron nitride polishing tool, and more particularly, to a method for producing chromium (Cr),
At least two metals are selected from metals such as titanium (Ti), tin (Sn), cobalt (Co), nickel (Ni), iron (Fe), and tungsten (W) to form a brazing metal material. Polyethylene oxide, polyvinyl acetate, methyl cellulose,
Dextrin, amylodextrin, etc., at least one selected from water-soluble polymer substances or organic substances, added together with water as a binder to the brazing alloy material, welded the powder paste alloy material to the metal tool base material, and cubic The present invention relates to a liquid phase sintering brazing method for producing a boron nitride tool.

[0002]

2. Description of the Related Art The atomic structure of a cubic boron nitride powder is different from that of a metal, and it is difficult to bond it as a cubic boron nitride tool. Therefore, a method of bonding cubic boron nitride powder with a steel metal tool base material has been widely adopted as a method for manufacturing a boron nitride tool.

In recent years, there has been proposed a method for producing a cubic boron nitride tool by electroplating at room temperature. Cubic boron nitride powder is physically bonded to the nickel-based welding material, but since the cubic boron nitride powder is non-conductive, it prevents the bonding between the cubic boron nitride powder and the welding material during electroplating. A concave portion is formed in a local portion of the surface of the welding material where the two are bonded, and the bonding strength is reduced. On the other hand, the physical connection between the welding material and the base material of the steel metal tool is weak, and the welding material for electroplating is often easily peeled off entirely. Thus, in the cubic boron nitride tool formed by the electroplating method, after the cubic boron nitride powder exposed on the surface of the welding material is highly worn, the nickel-based welding material having a very high hardness is not worn away. In fact, the effect of using the cubic boron nitride powder was small in practice because a new cubic boron nitride blade was exposed instead.

In another method of manufacturing a cubic boron nitride tool using a nickel-based high-hardness welding material, a hard and brittle base material must withstand vibration of equipment during use due to thermal stress. And shorten the life of the cubic boron nitride tool. Since the eutectic melting point of the nickel-based welding material is high, its deterioration must be prevented by using higher-grade cubic boron nitride powder. In the past, there has been proposed a method of manufacturing a cubic boron nitride tool by utilizing the property that Ti remains due to the thermal decomposition of TiH powder, in which a titanium plating layer is applied to the joint surface of the cubic boron nitride powder and brazed with a welding material. However, this manufacturing process was divided into two steps, and had a disadvantage that it became complicated.

[0005] In addition, there has been a method of manufacturing a cubic boron nitride tool using a pre-synthesized alloy piece as a welding material. It is extremely unsuitable for joining a boron nitride tool surface, and its quality is difficult to control.

As mentioned above, the choice of brazing metal material and the preparation of the paste binder are very important for the production of cubic boron nitride tools, but unfortunately the current industry still has problems in this area. The reality is that a method of manufacturing a cubic boron nitride tool that can be effectively solved cannot be devised.

[0007]

In view of the above circumstances,
The present invention provides a brazing by liquid phase brazing method (brazing by liquid phase sintering) for producing a cubic boron nitride tool by brazing a metal tool base material by using an alloy powder paste material as a welding material with copper as a base material. Then, it is intended to solve a problem which has not been solved by the conventional technology.

[0008]

Means for Solving the Problems As means for solving the problems, the present invention provides chromium, titanium, tin, cobalt,
Nickel, iron, at least two selected from metals such as tungsten and added to the brazing metal material, further, polyethylene glycol, polyethylene oxide,
Polyvinyl acetate, methylcellulose, dextrin, at least one selected from organic substances such as amylodextrin or organic substances, and added as a binder with water to a metal material for brazing, as an alloy powder paste material, as a metal tool substrate And a liquid phase sintering brazing method for producing a cubic boron nitride tool.

The present invention can be specified as follows.

(1) In a liquid-phase sintering brazing method for producing a cubic boron nitride tool by brazing a metal tool substrate by using an alloy powder paste material containing copper as a welding material, At least two selected from the group consisting of chromium, titanium, tin, nickel, tungsten, iron and cobalt are added as a brazing metal material to the welding powder alloy, wherein the brazing metal material is cubic nitrided. Binding boron to a steel metal tool base material; and further comprising at least one water-soluble polymer selected from the group consisting of polyethylene glycol, polyethylene oxide, polyvinyl acetate, methylcellulose, dextrin and amylodextrin in the brazing metal material. Add the substance as a binder with water Here, the weight ratio of the selected metal elements is 0.005 to 0.05 for chromium, 0.005 to 0.20 for titanium, and 0.000001 to 0. 0 for tin.
20, 0.000001 to 0.005 for nickel, 0.000001 to 0.005 for tungsten, 0 for iron
0.005, 0.000001 to 0.005 for cobalt
A method for producing a cubic boron nitride polishing tool.

(2) The weight ratio of the binder added is 0.000001 to 0.
1, polyethylene oxide is 0.000001 to 0.1.
1. Polyvinyl acetate is 0.000001-0.
1, 0.000001-0.1 for methylcellulose, 0.000001-0.1 for dextrin, 0.000001-0.1 for amylodextrin, 0.1-0.0 for water.
2. The method according to the above 1, wherein the method is 2.

Here, the brazing metal material is preferably selected from the group consisting of chromium, titanium, tin and nickel, and the selected metal element has a weight ratio of chromium of 0.01 to 0.02, tin 0.05 to 0.15 for titanium, 0.05 to 0.15 for titanium, 0.01 to 0.1 for nickel.
A range of 02 is preferred. Further, the water-soluble polymer substance is preferably polyvinyl acetate or methyl cellulose, and particularly preferably polyvinyl acetate.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The objects, configurations and effects of the present invention will be easily understood by referring to the drawings for the following embodiments of the present invention.

FIG. 1 shows a method of manufacturing a cubic boron nitride tool according to the present invention. In that step, a brazing metal material powder (granules) and a water-soluble binder are prepared, and the brazing metal material powder, a water-soluble binder and water in an appropriate ratio are mixed and stirred to form a paste welding material. After that, cubic boron nitride powder was sprayed on the paste welding material, and reduced or vacuumed.
And sintering and brazing the cubic boron nitride powder simply and quickly to produce a cubic boron nitride tool according to the common sintering operation temperature curve shown in FIG. FIG. 3 is a photograph of the product, and FIG. 4 is a photograph showing the structure of the product under a microscope.

The metal material for brazing is at least two selected from metal elements such as chromium, titanium, tin, cobalt, nickel, iron and tungsten. As the binder, polyethylene glycol, polyethylene oxide, polyvinyl acetate, methyl cellulose Dextrin, amylodextrin, or other water-soluble high-molecular substances or organic substances.

The weight ratio of the above metal elements is expressed assuming that the sum of the copper used and the metal elements is 1, and chromium is 0.000000.
1 to 0.05, 0.005 to 0.30 for titanium, mainly nitrides are generated by chemical reaction when brazing by liquid phase sintering, and joining is performed. In addition, the metal phase becomes excessive, the metal welding material becomes too hard and brittle, and the eutectic temperature of the copper-based welding material is increased, and the wetting angle is greatly increased. On the other hand, if the content of titanium is too small, the wet bonding property is remarkably reduced, and if the content of titanium exceeds 30%, the metal phase of the metal welding material becomes excessive. Too fragile and the cubic boron nitride tool is easily broken by thermal stress. Therefore, it is necessary to control the amount of addition.

The weight ratio of tin added is 0.00000
1 to 0.30, which utilizes the point of lowering the eutectic melting point of the copper-based welding material, which is the main effect of the tin element, and uses a relatively low temperature when brazing by liquid phase sintering. Sinter brazing of cubic boron nitride tools can be completed.
However, if the weight ratio of tin exceeds 30%, the eutectic melting point of the copper-based welding material becomes too low, which is disadvantageous for the practical application of cubic boron nitride tools, Due to the extremely high vapor pressure of the elements, too much tin content causes bubbles in the weld material which greatly hinders the progress of sintering and reduces the quality of the cubic boron nitride tool.

Addition of trace amounts of cobalt, nickel, iron, and tungsten elements in a weight ratio of 0.000001 to 0.005 to a metal welding material strengthens the copper-based welding material, but the content is too large. In addition, the eutectic melting point temperature and the wetting angle of the copper-based welding material are excessively increased, which adversely affects the production of cubic boron nitride tools by liquid phase sintering brazing.

The weight ratio of the binder is generally in the range of 0.0001% to 0.1% based on the total amount of the copper and the metal element used.
% And water ranges from 0.1% to 0.2%. If the binder weight ratio is too large, the amount of the welding material metal powder in the paste is reduced to reduce the liquid phase (welding material) during liquid phase sintering brazing, or a large amount of pores are formed in the welding material. Therefore, the bonding of the cubic boron nitride powder was weakened, and the viscosity and the wetting angle of the welding material powder serum became too large, and when the serum was coated on the steel metal tool base material, the surface thickness of the coating became uneven, As a result, the flatness of the cubic boron nitride tool surface after the liquid phase sintering brazing is affected. On the other hand, if the content of the binder is excessive, the amount of degreasing is high, a large amount of carbon-based contaminants remains, and the carbon component in the high-temperature state of the production system becomes extremely high. This has a significant effect on the manufacturing process, and increases the variation in product quality between different lots.

The method of manufacturing a cubic boron nitride tool (CBN Tools) by liquid phase sintering brazing using copper as a base material and an alloy powder paste material as a welding material according to the present invention is a conventional cubic boron nitride tool by electroplating. There is a significant difference in the bonding ability between the cubic boron nitride powder and the metal tool substrate as compared to the method of manufacture. The differences are listed in Tables 1 and 2 below.

[0021]

[Table 1]

[0022]

[Table 2]

The method for producing a cubic boron nitride tool by liquid phase sintering brazing using a copper base material and an alloy powder paste material as a welding material according to the present invention is a conventional method for producing a cubic boron nitride tool using a nickel welding base material. Compared to the method, there is a significant difference in the bonding ability between the cubic boron nitride powder and the metal tool substrate. The differences are shown in Tables 3 to 6 below.

[0024]

[Table 3]

[0025]

[Table 4]

[0026]

[Table 5]

[0027]

[Table 6]

Here, the hardness is based on Vickers hardness, and the thermal conductivity is determined by laser measurement (watt / mete).
r.kelvin).

[0029]

The method of manufacturing a cubic boron nitride tool by liquid phase sintering brazing using a copper base material and an alloy powder paste material as a welding material according to the present invention is mainly based on powder metallurgy liquid phase sintering. Applying the principle of the above, Chromium and Titanium in copper-based brazing metal materials have high activity and wet binding property to Cubic Boron Nitride and copper such as Chromium, Titanium, Cobalt, Nickel, Iron, Tungsten etc. Utilizing the property of improving the strength and hardness of the basic brazing metal material, the tin element lowers the melting point temperature of the brazing metal material, thereby increasing the required temperature, time and time required for liquid phase sintering brazing of cubic boron nitride tools. Chromium and titanium elements at lower liquid-phase sintering brazing operating temperatures After the phase of sintering brazing, the properties of chromium and titanium elements are exhibited at the operating temperature and a liquid phase is formed, the cubic boron nitride powder is rearranged on the steel metal tool base material and the nitride interface layer is formed on the cubic boron nitride surface And brazing cubic boron nitride on a metal tool substrate,
An effect of manufacturing a cubic boron nitride tool is provided.
Tables 7 and 8 show the advantages of the present invention.

[0030]

[Table 7]

[0031]

[Table 8]

[Brief description of the drawings]

FIG. 1 is a flowchart of a manufacturing process of the present invention.

FIG. 2 is a view showing an operation temperature curve of liquid layer sintering brazing according to the present invention.

FIG. 3 is a view showing a cubic boron nitride tool completed according to the present invention.

FIG. 4 is a drawing of a microstructure of a cubic boron nitride tool completed according to the present invention.

FIG. 5 is a drawing of a microstructure showing a bonding phenomenon of the cubic boron nitride tool of the present invention.

FIG. 6 is a drawing of a microstructure showing a bonding phenomenon of a cubic boron nitride tool manufactured by a conventional electroplating method.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI B24D 3/00 340 B24D 3/00 340 3/06 3/06 A

Claims (2)

[Claims] 1. A liquid phase sintering brazing method for producing a cubic boron nitride tool by brazing a metal tool substrate with an alloy powder paste material based on copper as a welding material, wherein the copper is used as a substrate. In the powder alloy for welding, at least two metals selected from the group consisting of chromium, titanium, tin, nickel, tungsten, iron and cobalt are selected and added as a brazing metal material, wherein the brazing metal material is cubic boron nitride. And a steel metal tool substrate; and further comprising, in the brazing metal material, polyethylene glycol, polyethylene oxide,
Polyvinyl acetate, methylcellulose, dextrin and amylodextrin, at least one water-soluble polymer selected from the group consisting of water and a binder are added together with water; wherein the weight ratio of the selected metal element is
Chromium is 0.005-0.05, titanium is 0.005-
0.20, tin is 0.000001 to 0.20, nickel is 0.000001 to 0.005, and tungsten is 0.1 to 0.20.
A method for producing a cubic boron nitride polishing tool, wherein 000001 to 0.005, iron is 0 to 0.005, and cobalt is 0.000001 to 0.005. 2. The weight ratio of the binder added is 0.000001 to 0.1 for polyethylene glycol, 0.000001 to 0.1 for polyethylene oxide, 0.000001 to 0.1 for polyvinyl acetate, and methylcellulose. Is 0.000001-0.1, dextrin is 0.000001-0.1, and amylodextrin is 0.1.
2. The method according to claim 1, wherein the amount of water is from 0.1 to 0.2 and the amount of water is from 0.1 to 0.2.