SU979097A1 - Method of making abrasive tool - Google Patents

Description

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This invention relates to the manufacture of an abrasive tool.

A known method of manufacturing an abrasive tool, in which the abrasive mass is placed in a mold that is installed in a magnetic field, after which the tool is molded, pressed and heat treated 1.

The magnetic field promotes the orientation of abrasive grains, pre-coated with metal, along magnetic lines of force.

The disadvantage of the method is that the abrasive grains are not fully oriented in the entire volume of the tool.

The aim of the invention is to improve the quality of the tool due to the full orientation of the abrasive grains throughout the tool.

The goal is achieved by the fact that in the method of making a tool, which includes forming a preform from abrasive mass with simultaneous orientation of abrasive grains, its subsequent extrusion in a mold and heat treatment, the preform is molded to provide a plastic flow of abrasive mass into which a temporary binder is preliminarily inserted an amount equal to the pore volume of the free mass, and when pressing the time, the binder is removed through the gaps of the mold.

The method is carried out as follows.

Preformed nonporous preforms by impregnating an abrasive mass consisting of a binder and abrasive grains with a temporary binder. Low-strength plastic and low-melting materials, such as wax, darafin, and the like, are used as a temporary binder.

The resulting blanks fill the extruder container, heat the blanks to the softening temperature of the temporary binder, squeeze the mass into the mold. The mass extruded into the mold is pressed, with the temporary binder extruding through the gaps of the mold. Pressing the billet is heat-treated and joined to the body.

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FIG. 1 shows the form in which the blanks are produced; in fig. 2 extruder extruder; in fig. 3 - pressing of the blanks after their extrusion, and to the left of the axis the position of the abrasive mass is shown before pressing, to the right - after pressing.

To obtain the preforms, a tablet 2 is made of the material of the temporary binder in the form 1. The abrasive mass 3 is then closed. Then the mold is heated until the tablet 2 is melted. At the same time, the mass is immersed in the molten temporary bond. Excess amount of temporary binding is removed from the mold. For this, the piston 4 abrasive mass, which is temporarily bonded, is lifted up to the alignment of surfaces 5 and 6. Starting from the time-bundle removed from the excess volume removed from the mold, the necessary volume of the tablet 2 is molded, after the solidification and hardening of the temporary bond, the preform is removed from the mold.

The obtained blanks are periodically filled with the container of the extruder 7, and at the softening temperature of the temporary binder, the mass is squeezed into the receiving chamber of the mold 8 by the punch 9.

The plastic flow at the entrance to the slit 10 cuts the tongues holding 11 the tongue 12. However, upon further movement due to narrower} 1 and shch11 9, the dissected flows again join.,

With the extruder zipus, the first molded blanks-rims are of poor quality. These crowns are extruded again. After establishing a stationary mode of operation, the extruder can be operated without interruption for stripping.

An extruded crown 13 is placed in the assembly mold 14. Preliminarily, a non-abrasive layer 15 is applied to the mold, which after sintering serves as the connecting link of the abrasive-bearing rim with the body.

The mold is heated to the melting temperature of the temporary binder. By melting, the time bond is partially removed from the mold, flowing out through its gaps 16 into the substrate.

17. During extrusion, not only abrasive grains, but also elongated metallic grains are oriented in an outflow direction. After partial removal of the temporary binder, at the same temperature, the abrasive mass is compacted at a pressure of 2000-4000 kgf / cm. Further, the manufacturing process of the tool continues according to the known technology, sintering, hot pressing, joining the abrasive bearing to the body and mechanical processing.

The final removal of the temporary binder occurs during sintering. However, with a large exhaust program, it is advisable, after removing the temporary binder by melting, to remove its residues in a drying oven with vapor collection and condensation.

An application for forming an extrusion billet of an abrasive mass with an excessive amount of temporary bond and its subsequent removal during the pressing process. cooking through the gaps of the mold contributes to a more complete orientation of the abrasive grains throughout the tool, which improves its cutting ability.

Claims (1)

Invention Formula A method of manufacturing an abrasive tool, in which a preform is formed from an abrasive mass with simultaneous orientation of abrasive grains in a mass, the billet is pressed into a mold and thermally processed, characterized in that, in order to improve the tool quality, the preform is molded with a plastic flow of abrasive mass in which a temporary binder is pre-inserted in an amount equal to the pore volume of the loosely poured mass, and in the process of pressing the binder, the binder is removed through the gap s molds. The sources of information taken into account in the examination 1. German Patent No. 617853, cl. 67 C, 1, pub. 1935 (prototype).