SU929328A1 - Method of producing flat parallel parts from copper powder - Google Patents

Description

(54) METHOD OF MANUFACTURING PLANE-PARALLEL PARTS FROM COPPER POWDER

one

The invention relates to powder metallurgy and can be used in the manufacture of high-precision copper structural parts of semiconductor devices.

A known method for producing structural parts, according to which, from a mixture of iron, copper and graphite powder with a specific force of 6 t / cm, parts are pressed and sintered in a protective medium at 11itO-ll80 ° C for 1.0-1.5 h of GO.

The disadvantage of this method is that it is not possible to obtain high precision parts due to uneven shrinkage during sintering.

The closest in technical essence to the present invention is a method by which parts are pressed under pressure of 4-5 tf / cm. The compacting of compacts is performed in a protective environment for 2 hours. After the first sintering, the parts are calibrated in,. the mold under pressure 6-7 ts / cm

and is secondarily sintered for 2 hours in a protective environment. The density of the parts obtained in this way is g / cm, hardness 28 kg / mm2-G21.

The disadvantage of the method is that it is practically not possible to obtain parts that meet high non-parallel requirements. This is due to the distortion of the press tooling.

In addition, burrs appear around the perimeter of the parts during calibration. This necessitates an additional operation to remove them, which increases the complexity of the preparation of parts.

The purpose of the invention is to improve the accuracy of parts in height and reduce the complexity of their manufacture.

This goal is achieved by the fact that according to the method the powder is compressed at an elevated pressure in mc / cm with the simultaneous formation of an annular groove along the perimeter of the part, sintering is carried out at 690-71 ° C, then the part is tampered and calibration is carried out with a free sediment at a pressure of kS ton / cm The implementation of pressing with a specific force of TC / cm allows to obtain the maximum density of pressed parts. Forming an annular process groove around the perimeter is necessary in order to avoid the appearance of burrs on the working surface of the parts. The sintering of parts at a temperature not exceeding 710 ° C allows their shape to remain unchanged, since swelling of parts is observed at higher temperatures. Lowering the sintering temperature from 1000 ° C to 700 ° C will save power energy. The tumbling of the sintered parts is produced to partially remove the burrs and to roll the remaining burrs into the cavity of the process groove. Calibration of parts free draft between parallel planes

0, OG

0.0020 0.0015 0.0017

0,0036

In the table it is designated: And - the copper detail made by a known method. Manufacturing mode: specific pressing force 5 ts / cm, 1st sintering temperature, specific calibration force 7 ts / cm 2nd sintering temperature 1000 ° C.

31.0

There are burrs on the working surface of the parts, up to about 0 mm high.

There are no defects

72.0 75.0 There are no defects 65.0

Calibrated parts have cracks on the cylindrical part.

Details after baking

77.0 swell

Claims (2)

V., VL-copper parts manufactured according to the proposed method: B - with lower bound values of the parameters (specific pressing force 7 tf / cm, sintering temperature 690 ° С, specific calibration force t ts / cm), B "j - with the top, it allows to obtain high accuracy of parts in height, using the simplest tool and increasing the calibration performance several times. Copper contacts for DT-20 semiconductor valves were manufactured using the proposed method. Sizes of parts: diameter 4.6 mm, height 1.0 mm. Copper powder of the PMS-1 brand, GOST 7960-69- was used as the starting material. Pressing was carried out on a rotary machine of the type PRM-1. Sintering compacts produced in a vacuum of 5-10 mm Hg for 2 hours. The tumbling of the parts after sintering was performed in a laboratory ball mill at a rotation speed of 60 rpm for 20 minutes (without balls). Calibration was performed on a hydraulic press free draft on the stop. For comparison, parts are made of copper powder according to the technology of a known method and the proposed method. The results of measurements of part dimensions, non-parallelism, density and hardness are shown in the table. their values of the specified parameters (specific pressing force of 8 tf / cm, sintering temperature UYU, specific calibration force of 5 tf / cm). Bj, 84. - copper parts manufactured according to the proposed method: B - with parameter values below the boundary values of the specified parameters (specific pressing force 6 t / cm, sintering temperature 670 ° C, specific calibration force 3 t / cm) , V. with the values of the parameters, above the boundary values of the claimed parameters (specific pressing force of 9 tf / cm, sintering temperature, specifically, the calibration force of 6 tf / cm). It can be seen from the table that the heights of the heights of the parts are less in the case of their manufacture according to the proposed method. N -.-- Invention Method for Manufacturing Copper-Powder Flat-Part Parts Including Pressing, Sintering, and Calibration, characterized in that, in order to increase accuracy and reduce labor-intensive parts, the powder is compacted at a pressure of 7-8 tf / cm while forming an annular groove around the perimeter of the part, making the hole at 690710 s, then the part is tacking, and calibration is carried out freely by slump at a pressure of A-5 tf / cm. Sources of information taken into account in the examination of 1.V znikov N.F. and Ermakov S.S. Metal-ceramic materials and products. L., Mechanical Engineering, 1967 p. 139. 2. Properties of metal powders, refractory co-compounds, unions and sintered materials. Information guide. K., Naukovy Dumka, 1978, i with .. 70.