RU2555270C2 - Composition of diamond tool - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: composition contains, mass fraction: diene synthetic rubber 100; organic peroxide 0.5-15; oligoester acrylates 5-30; mineral additive 30-200; metal powder 100-800 and diamond powder 5-150. Copper, bronze, iron, tin etc. powders are used as metal powders. Mixture of silicon oxide, aluminium oxide and zinc oxide is used as mineral additive.

EFFECT: diamond tool of specified composition ensures machining at high speed and tool load ensuring high productivity and low roughness of the machined surface.

2 cl, 3 tbl, 1 ex

Description

The invention relates to compositions of a diamond tool for producing surfaces of non-metallic materials with low roughness values during grinding and can be used to increase the intensity of machining at high speeds and tool loads.

Known diamond tools [1] based on diamond-rubber composites and diamond-containing polymer composites containing metal powders that increase the heat and thermal conductivity of the bundles. However, instruments on volcanic (rubber) bonds with a sulfuric vulcanizing group have low heat resistance and, as a result, they quickly lose their working capacity under mechanical conditions in harsh conditions.

Diamond tools with polymer bonds containing copper powder or a mixture of metal powders have sufficiently high heat resistance values, however, tools of this composition are highly brittle, which leads to their premature failure under intensive machining conditions, and also cannot provide low roughness values for the machined surface .

The closest in technical essence to the proposed invention is the composition of a diamond tool for grinding hard-to-handle non-metallic materials [2], containing, by weight:

       diene synthetic rubber 100

       organic peroxide 0.5-5.0

       mineral filler 40-120

       carbon black 5-50

       titanium hydride 10-50

       plasticizer 5-20

       diamond powder 5-150,

where as a mineral filler using a mixture of oxides of silicon, aluminum and iron in the ratio, parts by weight:

                silica 10-100

                alumina 10-100

                iron oxide 10-60

Such a tool has high values of hardness and strength, provides high performance with low roughness of the processed surface. The disadvantage of this tool is the low heat resistance associated with a low coefficient of thermal conductivity, which, under intensive grinding conditions, leads to a premature loss of the cutting ability of the tool (salting).

The technical result achieved by the claimed solution is to ensure, when using the proposed diamond tool, to increase the stability of the intensive modes of the machining process at high productivity and low roughness of the processed surface due to changes in its composition.

This is achieved by the fact that in the composition of a diamond tool containing diene synthetic rubber, organic peroxide, oligoester acrylate as a plasticizer, mineral filler and diamond powder, finely dispersed metal powder is additionally introduced.

It is advisable that the components of the diamond tool were taken in the following ratio, parts by weight:

                 Diene Synthetic Rubber 100

                 Organic Peroxide 0.5 - 15

                 Oligoether acrylate 5 - 30

                Mineral filler 30 - 200

                Metal powder 100 - 800

                Diamond powder 5 - 150

In this case, powders of copper, bronze, iron, nickel, tin, etc. are used as a metal powder, and a mixture of oxides in the ratio, parts by weight, is used as a mineral filler.

               Silica 10 - 80

      Alumina 10 - 80

               Zinc oxide 10 - 120

In the study of the distinguishing features of the described composition of the diamond tool did not reveal any similar known decisions regarding the composition of the claimed composition.

Thus, the claimed technical solution meets the condition of "NEW".

Comparison of the claimed technical solution not only with the prototype, but also with other technical solutions in the given field of technology [1, 2] shows that the claimed solution does not follow for the specialist explicitly from the prior art determined by the applicant; that it does not reveal signs that distinguish this technical solution from the prototype, and does not reveal the effect of the transformations provided for by the essential features of the claimed invention on the achievement of the technical result.

Therefore, the claimed technical solution meets the condition "INVENTIVE LEVEL".

The composition is prepared by mixing the components on a rubber mixing roller, vulcanizing the tool blanks in a mold under pressure on a vulcanizing press and heat treating them in a free state at a temperature of 280-300 ° C.

Diamond tools with polymer bonds for intensive grinding conditions with increased values of the load on the tool and high cutting speeds should have high wear resistance, which depends, first of all, on the strength of the bond, as well as its heat resistance and thermal conductivity.

The heat resistance and thermal conductivity of the bundles of diamond tools based on polymer compositions, in addition, is necessary to exclude destructive processes in the composite matrix caused by its heating during interaction with the treated surface, as well as to prevent burn-out of diamond grain or its incorporation into the tool bundle when it is softened during heating caused by intense force friction.

The presence of a metal filler with high thermal conductivity provides intensive heat removal, both from diamond grains and from the working layer of a diamond tool, thereby preventing its heating and the introduction of diamond into a bundle.

Mineral fillers help to increase bond hardness and diamond tool self-sharpening.

Silicon oxide, as well as zinc oxide, as reinforcing fillers, provide for the structuring of the rubber matrix, which leads to a durable and wear-resistant composite. In addition, zinc oxide is a component that increases the heat resistance of the rubber composition. Alumina helps to increase the hardness of the binder and, thus, increases the cutting ability of the tool.

To reduce the viscosity and improve the dispersibility of the solid powder components in the rubber matrix, oligoether acrylate is introduced into the composition as a temporary plasticizer. During vulcanization and heat treatment, such a component having active functional groups plays the role of an adhesive additive that promotes the chemical interaction between the rubber matrix and the surface of the solid particles of fillers and, therefore, the strong fixation of diamond grains in the binder, increase the strength properties and wear resistance of the diamond tool.

Achieving the claimed effect is provided by the above set of components of the rubber composition. The number of components in the composition of the composition is determined by both the ability to process the composition and the technological aspects of the diamond tool. For example, when working on grinding machines by grinding, the amount of metal powder introduced into the tool should not be high, and the amount of mineral fillers should not be high. When compiling a diamond ring tool for working in rigid axes, the content of metal powder and zinc oxide should be increased.

Example 1

A diamond tool is prepared as follows: on a rubber mixing roller, the rubber mixture is mixed in accordance with the composition shown in table 1, example 1. The resulting mixture is loaded into a mold, molded in a vulcanizing press and kept at a pressure of 5 ± 0.2 MPa, at temperature 170 ± 5 ° С for 10 minutes.

The obtained elastic blanks in the form of tablet elements with a diameter of 10 mm and a height of 5 mm, or rings with a size of 50x40x7 mm, are placed in an oven and subjected to heat treatment in a free state at a temperature of 300 ° C for 4 hours.

Tools in the form of tablet elements were tested by the method of free grinding in a grinding machine. The specific pressure on the tool was 2.5 kg / cm², the spindle speed was 1200 rpm. During the tests, quartz glass preforms were processed. The test results are presented in table 2.

Tools in the form of rings were glued to metal housings and tested on a machine such as a machining center using the "hard axis" method. The tests were carried out with the following machine settings:

- tool spindle rotation speed - 67 sˉ¹ (4000 rpm);

- spindle rotation speed of the part - 6.7 sˉ¹ (400 rpm);

- feed speed of the spindle parts - 200 microns / min.

Quartz glass flat parts with a diameter of 40 mm were processed. The test results are shown in table 3.

Examples 2 to 7

Table 1 shows the compositions for the preparation of diamond tools, differing in the number and nature of metal powders and other components. The methodology for manufacturing and testing diamond tools is similar to that described in example 1. The maximum allowable concentrations are presented on the example of the main component - metal powder. The influence of the amount of mineral fillers in the bunch on the performance indicators of the tools is also shown.

Tables 2 and 3 show the test results of the instruments, the compositions of which are presented in table 1.

From the presented test results it is seen that the tools of compositions 1 and 2 work effectively both in processes using the lapping method, and when working according to the "hard axis" method. The limiting content of metal powder leads to low resistance and high wear of the tool (example 3). The low content of metal filler (example 4) leads to a loss of cutting ability of the tool due to insufficient heat resistance of the binder. The content of the bronze powder above the claimed (example 5) contributes to the low wear resistance of the tool and the loss of its shape resistance. The content of mineral fillers below the claimed (example 6) leads to a loss of stability of the tool, and an excessive amount (example 7) leads to large wear.

As can be seen from the test results (examples 1, 2 and 3), the claimed compositions of diamond tools effectively work in harsh conditions.

Therefore, the claimed technical solution meets the condition "INDUSTRIAL APPLICABILITY".

Information sources

1. Synthetic superhard materials. Kiev .: Naukova Dumka, 1986, v.2, 264 p.

2. RF patent 2358852 C2, class. B24D 3/22, 2006.

Table 1
Examples of compositions of diamond tools Component Name Formulation Examples one 2 3 four 5 6 7 Nitrile butadiene rubber one hundred one hundred one hundred one hundred one hundred one hundred one hundred Organic peroxide 3 3 3 3 3 3 3 Oligoester acrylate 10 12 fifteen 10 10 10 10 Copper powder 300 700 200 Bronze powder 600 fifty 900 Iron powder 800 Aluminium oxide fifty thirty twenty 70 thirty 5 60 Zinc oxide 70 thirty 40 80 10 10 one hundred Silica twenty 40 twenty 60 twenty 5 60 Diamond powder fifteen 35 25 75 25 twenty twenty

table 2
The performance indicators of diamond tools during grinding No.
at
measure Health indicators Manufacturer-
nost
grinding
μm / min Tool wear
% Surface roughness, Ra,
μm The number of machined surfaces before editing the tool, pcs. one 53 1,5 0.06 more than 200 2 40 3.8 0.1 more than 200 3 48 6.3 0.13 180 four eighteen 4.2 0.09 45 5 44 35 0.22 four 6 23 2.7 0.11 130 7 54 38 0.29 four

Table 3
The performance of diamond tools during processing by the method of "hard axes" Example No. Health indicators The removed allowance, microns Processing time, sec Surface roughness,
Ra, μm The number of processed surfaces
before editing the tool, pcs. Note one fifty eighteen 0.08 more than 200 2 fifty fifteen 0,03 more than 200 3 fifty 16 0.12 140 increased wear four fifty twenty 0.09 fifteen greasy 5 fifty fifteen 0.23 2 very heavy wear 6 fifty eighteen 0,07 35 greasy 7 fifty fifteen 0.32 2 very heavy wear

Claims (2)

1. The composition for the manufacture of diamond tools for grinding non-metallic materials, containing diamond powder, synthetic diene rubber, organic peroxide, mineral filler and oligoester acrylate, characterized in that it further comprises a metal powder in the following ratio, wt. hours:
diene synthetic rubber one hundred organic peroxide 0.5 15 mineral filler 30-200 oligoester acrylate 5-30 metal powder 100-800 diamond powder 5-150 2. The composition according to p. 1, characterized in that the powders of copper, bronze, iron, nickel, tin are used as a metal powder, and a mixture of silicon, aluminum and zinc oxides in the ratio, parts by weight, is used as a mineral filler:
silica 10-80 aluminium oxide 10-80 zinc oxide 10-120