JPH0224061A - Polishing molded body and manufacture thereof - Google Patents

Abstract

PURPOSE:To provide toughness and extension performance onto a polishing molded body and improve strength by mixing the copper-tin group alloy powder, nickel powder, and grinding abrasive grains and heating and baking said mixture and roll-pressing the obtained sintered body. CONSTITUTION:A desired polishing molded body is obtained by mixing the copper-tin group alloy powder, phosphorus-copper powder, nickel powder, and the grinding abrasive grains and heating and baking said mixture and roll- pressing the obtained sintered body. A polishing molded article contains phosphorus in 0.1-1.5wt.%, and the polishing molded article is provided with toughness and extension performance. Further, tin is contained in 5-20wt.%, and the strength of the polishing molded body is increased, and the cutting performance is improved. Further, nickel powder is contained in 5wt.% or less, and the nickel-tin group intermetallic compounds are dispersed and separated, and the superior cutting performance can be provided.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a sintered abrasive compact (hereinafter referred to as a sintered abrasive compact), particularly a metal real sintered abrasive compact suitable for surface precision grinding and cutter blades. and its manufacturing method. In the present invention, polishing is a general term including polishing, grinding, and cutting.

(Prior art) Metal bonded sintered abrasive molded bodies used in the following applications, particularly tire cent, sintered products using cubic boron nitride as abrasive grains (hereinafter referred to as super abrasive grains) The polished molded body is mainly made of copper-tin bond. Increasing the content of tin in this copper-tin based bond sintered body improves the grindability, or the material becomes hard and brittle.

Therefore, in production, it is necessary to go through a powder compaction process. This powder compaction process requires a compaction load of 3 to 5 tons/crn', so there is a limit to the production of large-sized sintered bodies. Furthermore, when used as a cutter blade, it is difficult to create a thin molded body through a powder compaction process, making it unsuitable for use in thin-blade cutters.

(Problems to be Solved by the Invention) The present invention provides a metal bonded sintered abrasive molded body that imparts toughness and malleability and has the necessary strength, and a method for producing the same, with the purpose of solving the problems in the prior art described above. It is about providing.

[Means to solve the problem]

The first and second aspects of the present invention are sintered abrasive compacts of phosphorous-containing copper-tin metal powder and abrasive grains, to which a small amount of nickel powder is added and sintered. be. The inventions in Items 3 and 4 relate to these desirable manufacturing methods.

In the present invention, it is most preferable to use a mixed powder of a phosphorus-copper powder and a copper-tin alloy powder as the phosphorus-containing copper-tin metal powder. A mixture of the outer phosphorous copper powder and tin powder, a copper-tin alloy powder containing phosphorus, etc. can also be used. In the case of mixing phosphorous copper powder and tin powder, the first stage of sintering is carried out at a temperature slightly higher than the melting point of tin, and after holding the temperature for about 30 minutes, the temperature is further increased to cause a considerable degree of sintering. Promote copper-tin alloying. Since there is a limit to the phosphorus content (solid solution) in a copper-tin alloy containing phosphorus, a relatively small phosphorus content is possible within the scope of the present invention.

The present invention further includes a predetermined amount of nickel in the above invention. By adding nickel to disperse and precipitate a nickel-tin intermetallic compound, extremely good performance is imparted to surface precision grinding and cutter blades.

In the present invention, the real metal powder used is, for example, atomized powder. The tin content in this metal is 5 to 20% by weight, which is suitable for use.

If it is less than 5% by weight, the hardness will be insufficient and the grinding and cutting performance will deteriorate, and if it is more than 20% by weight, it will be difficult to manufacture a rolled product.

In addition, nickel powder that forms intermetallic compounds in the bond metal may be used as long as it has a particle size of 100 mesh or less, or the intermetallic compounds formed must be uniformly dispersed and precipitated to fully contribute to grinding and cutting. There is a need to. For this purpose, a material with a large particle size is preferable, and carbonyl nickel is optimal. The amount is 0.2-5% by weight
However, addition of more than 5% by weight makes the bond material hard and brittle, making it difficult to manufacture rolled products.

Phosphorus in the copper-tin metal forms phosphor bronze in the sintered body, imparting toughness and malleability to the bond metal and, therefore, to the sintered body. If the phosphorus content is too low, this property cannot be achieved, so it is necessary to allow 0.1% by weight or more to remain in the metal. On the other hand, if the amount is too large, the strength of the sintered body will be reduced. The decrease in strength can be compensated to some extent by adjusting the tin content, and it is desirable to suppress the phosphorus content to 1.5% by weight or less in the metal.

Next, the grinding abrasive grains used in the molded article of the present invention will be explained. Suitable abrasive grains are usually super-grinding abrasive grains, preferably mixed with general grinding abrasive grains in order to uniformly grind the ground or cut surface.

As super-grinding abrasive grains, 0.3 to 10% by weight of 1/4 to 200 well Tiemon and/or cubic boron nitride are used.
Mix. These abrasive grains may be used alone or their surfaces may be coated with nickel, copper, tin, etc. It is better to use coated abrasive grains for better wettability with bond metal, and it is better to mix a large amount of abrasive grains. obtain. When using coated abrasive grains, it is necessary to subtract the amount of coated metal from the composition of the real metal in advance, and finally adjust the overall composition.

As general abrasive grains, carbide-based abrasive grains such as silicon carbide and tungsten carbide, and/or oxide-based abrasive grains such as aluminum oxide and silicon oxide are preferably used. These general grinding abrasive grains are softer than super-grinding abrasive grains, so they do not contribute much to grinding and cutting, or they have the effect of erasing the streaks peculiar to fixed abrasive grains and the dressing effect of preventing clogging of the sintered body. have.

In order to fully achieve these effects, it is necessary to take into account the particle size and amount of super-abrasive grains and general grinding grains. It is also necessary to consider the material to be cut. If the workpiece material is brittle, use 115 or the same amount of general grinding grains that are the same or finer than the super-grinding abrasive grains, and if the work material is soft, use the same or finer grain size than the super-grinding grains. It is best to add about the same amount or twice the amount of coarse general grinding abrasive grains.

The method for producing a sintered abrasive compact of the present invention preferably uses phosphorous copper powder and copper-tin alloy powder as starting materials for the bond metal.

The phosphorus content of the phosphorous copper powder is preferably from 0.5 to 12.0% by weight. In addition, in this case, the copper-tin alloy has a tin content of 1
0 to 23 weight is suitable.

Then, nickel powder is added to these materials to further contain nickel. It is desirable that these powders have a weight of less than 100 mU.

These starting materials are thoroughly mixed with grinding abrasive grains, placed in a mold, and sintered under pressure under a low load of about 50 g/cm'. The sintered body is then rolled. This rolling is one of the characteristics of the method of the present invention. This makes it possible to easily produce thin and large molded bodies. Sintering may be performed at a temperature of 600 to 800°C for 30 to 60 minutes. The atmosphere at this time can be vacuum, inert, or reducing, or is preferably vacuum or reducing atmosphere in order to prevent oxidation of metals, super-abrasive grains, etc. and improve sinterability. Rolling can be done at room temperature. For rolling, unidirectional rolling is preferred in order to finish the sintered body uniformly. The porosity decreases due to rolling, which can be adjusted by adding general abrasive grains.

Since the rolled product has oil adhering to it and is slightly hardened or deformed due to strain, the temperature of 600 to 800 °C is 30 to 6.
It is recommended that the annealing be performed for about 0 minutes, and if the rolled product is to be processed, it is recommended that the annealing be performed before this annealing.

During surface precision grinding, the sintered bodies created in this way are attached to a surface plate using a thermosetting adhesive or rubber adhesive to produce prisms, watch surface glass, marble, precious stones, Si wafers, and various ceramics. It can be used for grinding sintered bodies, and when set in a cutter, it can be used to cut precious stones, marble, granite, various single crystals, and various ceramic sintered bodies.

Next, the present invention will be explained with reference to Examples.

Example 1 Atomized bronze powder of 100 mesh or less (tin content 1
5% by weight) and atomized copper phosphorus powder (phosphorus content: 8% by weight) of 100 Meushie or less (5:2 by weight), electroless nickel plating (55% by weight) is applied to the metal powder. 0.5% by weight of tire cent powder
Mix it, put it in a mold, and heat it in a hydrogen gas atmosphere at 6506C±.
Sintered for 45 minutes at 15°C and 145g/crn', length 17ca+, M! 114c++, thickness 0.61
A sintered body was obtained. Next, this sintered body was passed between rolling rolls at room temperature to form a rolled body having a thickness of 0.2 square centimeters. This rolled body was annealed for 30 minutes at 650°C ± 15°C in a hydrogen atmosphere, and then punched out with a diameter of 100 m and a width of 2.5 mm in 6 places.
1. A sheet with a cut having a length of 40 mm was obtained. The phosphorus content of this sheet was 0.74% by weight.

This sheet was attached to a flat polishing plate using an adhesive. Using this grinding tool, the surface roughness R□ is obtained by rough grinding. When a piece of flat glass with a diameter of 18 mm was ground, the following results were obtained.

Polishing machine: Oscar type glass polishing machine steel type
: BK-7, 70x 70 load:
500g/c lower plate rotation speed: 400rpm Coolant: 20x ethylene glycol liquid 5 minutes grinding amount: 200p Surface roughness after 5 minutes: R, , = 2 tiles grinding ratio (= glass grinding amount (le) / sheet Amount of polishing (extension)
: 100 Example 2 A sheet was obtained in exactly the same manner as in Example 1 except that 3% by weight of carbonyl nickel powder having an average particle size of 3 to 7 μm was added to the metal powder of Example 1. The phosphorus content of the sheet is 0.64
% by weight.

When glass was ground in the same manner as in Example 1, the following results were obtained.

Amount of grinding for 5 minutes - 260 tiles Surface roughness after 5 minutes: Rwraw = 2.29L Grinding ratio = 93 Example 3 Atomized bronze powder of 100 mesh or less (tin content 2
0 weight ψ%) and 100 mesh or less atomized phosphorous copper powder (phosphorus content 8 weight %) in a ratio of 5:2 by weight, and 2 weight parts of carbonyl nickel powder with an average particle size of 3 to 7 mm. Electroless nickel plating (
Tire cent powder of 50 to 100 p with plating weight of 55%) and silicon carbide powder (CC) of the same particle size as 0.0 p.
A sheet was obtained in the same manner as in Example 1 by adding 75% by weight. The groove content in this metal was 0.60%.

When a silicon carbide sintered body was ground in the same manner as in Example 1, the following results were obtained.

Amount of grinding for 5 minutes; Surface roughness after 60 ru for 5 minutes: R-JX = 374 grinding ratio
:50 Example 4 Electroless nickel plating (plating weight 55%) was applied to a powder obtained by adding 3% by weight of carbonyl nickel powder with an average particle size of 3 to 7μ to the same metal powder as in Example 3.
0.5ii% of cubic boron nitride powder, 12~
A sheet was obtained in the same manner as in Example 1 except that 1.0% by weight of aluminum oxide powder (1#A) was added. The phosphorus content of this sheet was 0.35% by weight. When a Si single crystal was ground in the same manner as in Example 1, the following results were obtained.

However, the kanzashi load was 70 g/crn', and the single crystal size was 4 inches φ.

Amount of grinding for 5 minutes: 65 JL Surface texture after 5 minutes: R, , , = 1.6 Pot grinding ratio: 250 Example 5 Atomized bronze powder of 100 mesh or less (tin content 20% by weight) and 100 mesh A base powder was prepared by adding 5% by weight of carbonyl nickel powder with an average particle size of 3 to 7p to a mixed powder of the following atomized copper phosphorus powder (phosphorus content: 8% by weight) in a ratio of 5:2 by weight. Region C=50 (C=100 is grade unit volume 1
4.4 carats per crn' = 0.88g) of diamonds (mesh size #120 /1
40) and silicon carbide of the same grain size well 120 were added, and heated at 680°C ± l in a hydrogen gas atmosphere as in Example 1.
Sintered at 155 g/cm' at O°C for 35 minutes,
A sintered body with a length of 17 (lsm, a width of 140 mm, and a thickness of 0.6*m) was obtained. Hereinafter, rolling and annealing were performed under the same conditions as shown in Example 1, and a sheet with a thickness of 0.2 mm was obtained. This was then processed into a shape with an outer diameter of 150 m5 and an inner diameter of 50.8 mm.

As a comparative example, a sheet was manufactured using atomized copper powder of the same particle size instead of the atomized phosphorous copper powder described above. However, the sintering temperature in this case is 850'C ± 10°C and 35
Hold for minutes. This sheet is referred to as Comparative Example 1. In addition, commercially available tire center resin rate (diamond particle size #
120. When a test was conducted under the following conditions using Comparative Example 2 (the dimensions are the same as above), as shown in Table 2, the product of the present invention exhibited excellent performance in machining hard and brittle materials such as SiC. It became clear that

Table 1. Cutting test conditions Cutting machine Creep foot molding grinder made by Okaki Kogyo 3180 rpm 20 mm/5 in 1, 3.5 m + * 3 types of rotation speed Table speed: Depth of cut Grinding fluid Work material Cutting method Water-soluble chemical type (60 times diluted) ) Sintered SiC Down Cut Table 2 Cutting Test Results (Note) The chipping amount is the average value obtained by observing the cut surface with a universal projector and measuring the 10 points with the largest chipping amount.

Claims (4)

[Claims] (1) Contains 0.1-1.5% phosphorus and 5-20% tin
A sintered rolled abrasive molded body of copper-tin metal powder of 5% by weight or less, nickel powder of 5% by weight or less, and grinding abrasive grains. (2) The sintered-rolled abrasive compact according to claim 1, wherein the abrasive grains are mainly composed of diamond or cubic boron nitride. (3) 0.1 to 1.5 weight characterized by rolling a sintered body obtained by mixing and heating sintering copper-tin alloy powder, phosphorous copper powder, nickel powder, and grinding abrasive grains. A method for producing a sintered rolled abrasive compact of copper-tin metal powder containing 5% to 20% by weight of tin, 5% by weight or less of nickel powder, and abrasive grains. (4) The method for producing a sintered rolled abrasive compact according to claim 3, wherein the abrasive grains are mainly composed of diamond or cubic boron nitride.