RU2146192C1 - Method for making high porosity abrasive tool - Google Patents

Abstract

FIELD: manufacture of abrasive tools, namely high porosity abrasive tools of white fused corundum with ceramic binder. SUBSTANCE: method of making high porosity abrasive tool comprises steps of mixing abrasive grains, ceramic binder, temporary binding material in such a way that it is not necessary to keep predetermined ratio of content and size of blowing agent and abrasive grains; using as blowing agent mixture of perlite sand and fruit kernels with ratio (1:10) -(10:1). EFFECT: reduced cost price of ready tools. 3 ex

Description

 The invention relates to the field of production of an abrasive tool, namely a highly porous abrasive tool made of electrocorundum on a ceramic bond, intended for deep grinding.

 A known method of manufacturing a highly porous tool [1], comprising mixing abrasive grain, ceramic binder, moisturizer, temporary binder, and fractionated perlite is used as a pore-forming. However, with this method, the use of perlite does not allow a relatively long storage of the mass and creates conditions for delamination in the raw material, which, as a rule, causes uneven hardness of the finished tool.

 There is also known a method [2] comprising mixing abrasive grain, a ceramic binder, a humidifier, a pore-forming filler from electrocorundum spherical particles, an organic burn-out filler (fruit seeds 400 microns in size) is additionally introduced. Such a mass makes it possible to obtain a fairly uniform pore skeleton in the instrument, but subject to strictly fractionated fruit seeds and certain ratios of spherical particles, grain and fruit seeds. This method significantly increases the cooking time of the mass, which complicates the technological cycle and at the same time increases the cost of the tool, due to the use of expensive spherical particles.

 The closest in technical essence to the claimed method is the method [3], we have chosen for the prototype. This method involves mixing abrasive grain, ceramic binder, humectant, temporary binder, fruit seeds, classified by grain size. However, the raw material obtained from such a mass has low mechanical strength, because moistened fruit seeds create the effect of “wedging” of the grain space, which leads to a high percentage of drying waste and, consequently, to an increase in the cost of the tool. In addition, as in the method [2], the use of strictly fractionated fruit seeds is required.

 The objective of the invention is the creation of a new method of manufacturing a highly porous abrasive tool, which allows to obtain the required technical results. The problem is achieved in that in the method for producing a highly porous tool, including mixing abrasive grain, ceramic binder, moisturizer, temporary binder, it is new to use as a pore-forming component a mixture of waste perlite sand and fruit seeds taken in a ratio of 1: 10-10: 1 .

 The method allows to obtain a highly porous, highly structural tool with uniform hardness. The raw material obtained in the manufacturing process of the tool is characterized by high mechanical strength (due to the high specific surface of the pore-forming mixture). The use of a mixture of perlite sand and fruit seeds as a pore-forming agent makes it possible to create a pore skeleton with a pore size in the range of 300-800 microns.

As abrasive grain in the proposed method use:
white electrocorundum grain according to GOST 2424-83 (the choice of grain size depends on the purpose of the tool),
as a ceramic bond - K5 bond according to TU 2-036-984-86,
as a humidifier and temporary binder, known to manufacturers of abrasive tools, water glass and dextrin.

 The quantitative ratio of the components of the blowing agent is 1:10 - 10: 1, and the choice of a specific ratio depends on the given hardness of the finished tool.

For the manufacture of an abrasive tool according to the proposed method, the calculated amounts of abrasive grain, ceramic binder, humidifier, temporary binder and pore former are mixed, the blanks are formed from the obtained abrasive mixture, which are kept under natural conditions for up to 48 hours depending on size, then they are dried at a temperature of 120 ^o C and fired at 1250 ^o C. After firing, the product is cooled and subjected to mechanical processing.

 The following are specific examples of the implementation of the proposed method.

Example 1
Prepare an abrasive mass of the following composition:
abrasive grain - 100 parts by weight, ceramic bond - 8 parts by weight, liquid glass - 4 parts by weight, dry dextrin - 3 parts by weight, water - 4 parts by weight, pore former - a mixture of perlite sand waste and fruit seeds in a ratio of 1: 10.

The resulting tool has:
- hardness M1-M2
- porosity 43%
- the pore size is from 300 to 500 microns.

Example 2
The mixture is prepared according to example 1, except that the ratio of waste perlite sand and fruit seeds is 7: 3.

The resulting tool has:
- hardness BM1-VM2
- porosity 56%
- the pore size is from 400 to 800 microns.

Example 3
Prepare the mixture according to example 1, except that the ratio of waste perlite sand and fruit seeds is 10: 1.

The resulting tool has:
- hardness M1
- porosity 52%.

 The proposed method provides a highly porous abrasive tool with uniform hardness and predetermined porosity. The method allows to reduce the cost of the finished tool, since the pore-forming mixture is waste perlite sand and fruit bones. The method differs in manufacturability, since there is no need to observe certain ratios of sizes and amounts of grain and pore-forming mixture.

 The tool manufactured by the proposed method has been tested at Perm Motors factories / g. Perm / and "Turbine blades" / St. Petersburg /.

Sources of information
1. Auth. St. USSR N 603574, B 24 D 3/18, BI 1978, N 15.

 2. Auth. St. USSR N 1685695, B 24 D 3/14 BI 1991, N 39.

 3. Auth. St. USSR N 1689355, C 04 B 35/10, B 24 D 3/18, BI 1991, N 41.

Claims (1)

 A method of manufacturing a highly porous abrasive tool, comprising mixing an abrasive grain, a ceramic binder, a moisturizer, a temporary binder and a blowing agent containing fruit bones, molding blanks from the resulting mixture, drying and roasting, characterized in that the blowing agent further comprises perlite sand waste at a ratio of 1 : 10 - 10: 1.