JPS60168534A - Synthesis of polishing particles - Google Patents

Abstract

PURPOSE:To prepare high strength, high hardness and high toughness polishing particles, in forming polishing particles by impulsively supplying a current to a stock material comprising a wire material of a metal or metal oxide in an atmosphere of hydrogen or carbon, by mixing a specific rare earth element in the aforementioned stock material. CONSTITUTION:A first stock material having a wire like, foil like or powderly shape selected from a group consisting of Ti, W, Nb, Ta, Zr, Hf and oxides thereof and a second stock material comprising one kind of a material selected from a group consisting of hydrocarbon, ammonia, carbon, carbon oxide, hydrogen, oxygen, nitrogen, water and boron or a mixture consisting of two or more kinds of said materials in said group are charged in one pressure container and a current is impulsively supplied to the first stock material in the atmosphere comprising the above metioned second stock material to explosively gassify the same while the gassified material is reacted with the second stock material to directly form polishing particles comprising carbide, nitride or boride of the above metioned metals or the like. In this method, 0.1-2wt% of a rare earth element is mixed in the first stock material. As a result, high strength, high hardness and high toughness polishing particles are obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for synthesizing abrasive grains, and particularly to a method for producing abrasive grains by applying an impact current to a metal or metal oxide wire, strip, powder, or the like.

Generally, abrasive grains used for grinding and the like are required to have properties such as high strength and hardness, and high toughness. Since the properties of this abrasive grain greatly affect machining speed and efficiency, there is a strong demand for the development of new abrasive grains with high strength, hardness, and toughness in order to improve machining speed and efficiency.

Therefore, carbides and nitrides such as titanium, tungsten, niobium, tantalum, zirconium, hafnium, silicon, and boron, which are the materials of abrasive grains, are produced by the reaction of these metals or metal oxides with carbon, carbon compounds, or nitrogen. However, in conventional methods, impurities such as oxides of these metals and free carbon remain in the product. In addition, these impurities often form solid solutions with metal carbides and metal nitrides, so it is extremely difficult to remove them from the generated material. However, it is difficult to obtain abrasive grains that have the required strength, hardness, and toughness, and it is difficult to obtain abrasive grains that have the required properties such as strength, hardness, and toughness. There was a problem that I couldn't get it.

In addition, two or more types of carbides such as titanium carbide, tungsten carbide, tantalum carbide, etc. may be mixed, and these may be mixed as a solid solution or as a composite.
Although abrasive grains used as composite compounds have been proposed, there is still a problem in that sufficiently satisfactory strength, hardness, toughness, etc. cannot be obtained.

For this reason, the inventors of the present invention have prepared a wire-shaped, foil-shaped, or shaped material selected from the group consisting of titanium, tungsten, niobium, tantalum, zirconium, hafnium, silicon, boron, and their oxides in one pressure vessel. A first raw material in the form of flakes or powder, and one or more selected from the group consisting of hydrocarbons, ammonia, carbon, carbon oxide, hydrogen, oxygen, nitrogen, water, and boron. A second raw material consisting of a mixture of the above is charged, and the first raw material is explosively vaporized by shockingly energizing it in an atmosphere consisting of the second raw material, and reacts with the second raw material. We proposed a method for directly producing abrasive grains made of carbides, nitrides, borides, etc. of the above-mentioned metals.

In addition, when producing a carbide, the second raw material may be, for example, carbon fine powder and its carrier gas, spraying with a hydrocarbon carrier gas, mixed gas of carbon oxide and reduced hydrogen, carbon oxide gas, etc. In the case of producing nitrides, for example, spraying with nitrogen gas, ammonia vapor, or carrier gas, and in the case of producing a mixture of carbides and nitrides, use the above-mentioned mixture or a carrier of the raw material for carbonization. This can be carried out by using nitrogen as the gas, or conversely by atomizing ammonia with carbon oxide, or by mixing fine carbon powder, and of course, boron needs to be supplied to produce boride. On the other hand, when the first raw material is an oxide, consideration is given to creating a reducing atmosphere during the reaction by discharge.

According to this method, the crystal size is uniform and purity is high;
Abrasive grains with excellent properties such as high strength, hardness, and toughness can be obtained.The present invention is a further improvement and development of the above method, and its gist is that titanium, tungsten, niobium, Lanthanum or cerium is used as the first raw material in the form of a wire, foil, strip, or powder selected from the group consisting of tantalum, zirconium, hafnium, silicon, i, and oxides thereof. , neodymium, samarium, yttrium, europium, praseodymium and other rare earth elements are mixed in a weight ratio of 0.1% or more and less than 2% (the same applies hereinafter) and reacted.

The most desirable addition amount of this rare earth element is 1.2% to 1.2%.
If the amount added is less than 0.1%, there will be no noticeable effect, and if the amount added is more than 2%, it will be harmful.

The abrasive grains produced in this way have uniform crystal sizes and less precipitation of impurities, which improves the strength, hardness and toughness of the abrasive grains, and if used for grinding etc., machining speed and processing efficiency can be significantly increased. This is something that can be improved.

Hereinafter, an example of lapping using abrasive grains synthesized by the abrasive grain synthesis method according to the present invention will be described.

Figure 1 shows the abrasive grains synthesized by the abrasive synthesis method according to the present invention.
A graph showing an example of machining using abrasive grains containing l"1Lac and TjCeC in comparison with a machining example using conventionally known abrasive grains.
It is a graph showing an example of machining using abrasive grains containing CN in comparison with a machining example using conventionally known abrasive grains.

In Figures 1 and 2, the vertical axis is the machining speed (g/m1n
), the horizontal axis both represent the machined surface roughness μRmax), and 1
2 is a straight line showing the experimental results when TiLaC (La 1% content) abrasive grains are used;
A straight line showing the results when using abrasive grains containing %), 3 is T
t Ce C (containing 1.2% Ce) abrasive grains are used, and 4 is a straight line showing the results when using abrasive grains of
．． This is a straight line showing the results when using abrasive grains containing 2% C, N), the dashed line shows the results when using diamond abrasive grains, and the dashed line shows the results when using conventional abrasive grains. This shows the results when using TiC abrasive grains.

Furthermore, the processing conditions are as follows: The number of rotations of the lap plate is 416,00 Or, p, m.

Workpiece: 5KD11 steel, hardness HRC65 Machining area: 1
The above abrasive grains were mixed with castor oil and used.

As shown in FIGS. 1 and 2, the abrasive grains synthesized by the abrasive grain synthesis method according to the present invention can further improve machining speed for the same machined surface roughness compared to conventional abrasive grains. I understand.

Since the present invention has a ridge-like structure, the present invention provides abrasive grains that have high strength, hardness, and toughness, and when used in grinding, etc., significantly improve processing speed and processing efficiency. can be done.

Note that the present invention is not limited to the embodiments on the ridges,
For example, in the above embodiment, lanthanum and cerium were used as the rare earth elements mixed into the first raw material, but neodymium, samarium, indolium, europium, praseodymium, etc. may also be used. It encompasses all of these.

[Brief explanation of drawings]

Figure 1 shows T synthesized by the abrasive grain synthesis method according to the present invention.
A graph showing an example of machining using abrasive grains containing i La C and Ti Ce C in comparison with a machining example using conventionally known abrasive grains. It is a graph showing an example of processing using abrasive grains as a component in comparison with a processing example using conventionally known abrasive grains. 1 ------------- Straight line 2 showing the experimental results when using Ti La C (La 1% content) abrasive grains 2 ----------Tt Ce C (Ce 1.
Straight line 3 shows the results when using abrasive grains containing 5% Ti Ce C (Ce 1
．． Straight line 4 shows the results when using abrasive grains containing TiCeCN (Ce 1%)
A straight line showing the results when using abrasive grains containing

Claims (1)

[Claims] In one pressure vessel, a material selected from the group consisting of titanium, tungsten, niobium, tantalum, zirconium, hafnium, and oxides thereof, in the form of a wire, foil, or powder, etc. First raw material, hydrocarbons, ammonia, carbon,
and a second raw material consisting of one or a mixture of two or more selected from the group consisting of carbon oxide, hydrogen, oxygen, nitrogen, water and boron, and in an atmosphere consisting of the second raw material. A method of explosively vaporizing the first raw material by shockingly energizing it, causing it to react with the second raw material, and directly producing abrasive grains made of carbides, nitrides, borides, etc. of the metals, etc. In the above first raw material, a rare earth element is added in a weight ratio of 0.1% or more2.
The abrasive grain synthesis method described above is characterized in that the abrasive grains are mixed within a range of less than %.