SU1456457A1 - Plasticizer for moulding powders - Google Patents

Abstract

The invention relates to the field of powder metallurgy, in particular to the preparation of a plasticizer used in the pressing of hard-to-form metal powders. The purpose of the invention is to increase the density of compacting high speed steel powders and to simplify the process of plasticizer preparation. Estimated; the amount of chloroprene copolymer (L-MMA-M) is dissolved in cold distilled water, triethanolamine and oleic acid are added. The plasticizer thus obtained is added in an amount of 120-140 ml per 1 kg of high-speed steel powder. The process of plasticizer preparation excludes the operations of mixing the individual components and their heating. The plasticizer allows compacting with optimum density. 1 tab. (/)

Description

I

The invention relates to powder metallurgy, in particular, to the production of a plasticizer used in the pressing process of hard-to-mold metal powders.

The aim of the invention is to increase the density of compacts from powders of high-speed steels and to simplify the process of plasticizer preparation.

The calculated amount of chloroprene copolymer (L-MMA-M) is dissolved in cold distilled water, then triethanolamine and oleic acid are added. A powder of high-speed steel RbM5, obtained by melting or vibropro mol, is loaded into the drum and plasticizer is added. Mixing is carried out on a roller table, a mixer for 3-4 hours. For each kilogram of powder, 120-140 ml of plasticizer of torus is taken. The mixture is dried at 50-60 ° C for 1.0-1.5 hours. The mixture from the sprayed powder of high-speed steel: requires a long drying time of 2.0-2.5 hours

After drying, from the resulting press mixture, the samples are pressed in steel molds at a pressure of 600.800 and 1000 MPa.

At the same time, to obtain comparative results, high-speed steel powder is loaded into the drum and a known plasticizer is introduced.

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31456457

To prepare a known plasticizer, the calculated amount of dry polyvinyl alcohol is dissolved in boiled water by stirring for 10-15 minutes. Separately, the required amount of stearic acid, triethanolamine and ethyl pyrth is mixed with heating

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0 ± 10 ° C for 5-15 minutes, and then it is added to a solution of polyvinyl alcohol with additional stirring for 5-10 minutes at room temperature. After mixing with the powder, ichts are dried in the same way.

Six compositions of the proposed plasticizer and one composition of the plasticizer are prepared with the following ratio of components, wt.%:

The proposed plasticizer

1. Chloroprene copolymer (3% solution) .8,5 Triethanol-, amine 1,5 Olein

Acid 1.5 Distilled water Else

2. Chloroprene copolymer (4% solution) 11.2 Triethanolamine2, 0

Oleinov

Acid 2, O Distilled Water Else

3. Chloroprene copolymer (5% solution) 14.0 Triethanolamine 2, 5

Oleinov

Acid 2.5 Distilled Water Else

4. Chloroprene copolymer (6% solution) 17.0 Triethanolamine 3, 0

Oleinov

acid 3.0

ten

15

20

25

one

thirty

op os off pr

m pl 40 right dust with at 45 vol.

50 ka according to nov ka in

ti ra

55

five

0

five

0

Distilled Water Else

5. Chloroprene copolymer (7% solution) 19.8

Triethanolamine 3, 5

Oleinov

acid 3,5

Distilled water Else

6. Chloroprene copolymer (8% solution) 22.4 Triethanolamine 4, 0

Oleinov

acid 4.0 Distilled water Else Lime lime plasticizer Polyvinyl alcohol (10% solution) 8.5

Triethanolamine 14, -O Stearinova

acid0.4.

Ethyl alcohol Water Else

The density of the compacts obtained was determined by hydrostatic weighing. The test results are presented in the table.

As can be seen from the table, the proposed plasticizer makes it possible to obtain dense compacts from practically no compressed powdered high-speed powders pressed in a cold state. (unlike the plasticizer of known composition, which does not provide for the preparation of compacts from molten powders (samples were dissolve).) The optimum density for pressing of high speed steels should be in the range of 5.35-5.91 g / cm 5.

The use of the proposed plasticizer for pressing compacts from powders produced by vibromomol: allows a significant increase in the density of compacts Compared with the known plasticizer and obtain high-quality compacts with a density in the range of 5.35-5.91 g / cm.

Use in the proposed plasticizer triethanolamine, which is soluble in water, and oleic acid

Lots that float on the surface of the resulting mixture allow one to exclude the formation of pressing cracks on the surface of samples.

It was established that the total content of triethanolamine and oleic acid should correspond to the percentage of chloroprene copolymer in solution. Thus, 2% triethanolamine and 2% oleic acid are added to a 4% aqueous solution of chloroprene copolymer.

The optimum content of chloroprene copolymer in water is 14.0 - 19.8 wt.%. With a higher content, due to viscosity, the uniformity of mixing of the plasticizer with the components of the charge is not achieved and the compressibility decreases, the porosity increases, and with a lower content, the porosity also increases.

The plasticizer of the proposed composition is obtained by simply mixing the f components for 1 minute and is evenly distributed in the charge, improving the plasticity of the charge and pressurization.

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In addition, the preparation process of the proposed plasticizer is much simpler compared to the known one (it is not necessary to heat the components, separate their preparation).

Claims (1)

Invention Formula A plasticizer for pressing powders containing triethanolamine, an organic acid and an aqueous polymer solution. and methacrylic acid, and, as an organic acid, oleic acid in the following ratio of components, May. : Chloro-copolymer prene Trie Tanolamine Oleic acid Distilled water 0 five 14.0-19.8 2.5-3.5 2.5-3.5 Rest . Powders, obtained by raspyleniy, with a pressure of pressing, MPa 600 800 1000 Powders obtained by vibro-grinding, with pressure of pressing, MPa1 600 800 1000 Races - 5.02 5.43 5.43 5.3 Sanders 5,10 Scattering 4.86 5.26 5.67 5.59 5.43 5.18 Scattering 4.94 5.43 5.93 5.85 5.59 5.35 Scattering 5.02 5.18 5.10 5.59 5.67 5.26 5.75 5.75 5.59 5.91 5.91 5.50 5.3 5.02 5.67 5.50 5.26 5.75 5.59 5.35 5,10 Scattering 5.59 5.35 5.50 5.3 5.02 5.67 5.50 5.26 5.75 5.59 5.35