DE454804C - Process for the production of molded articles - Google Patents

Description

Process for the production of moldings. To copper in finely divided In accordance with the invention, a solution of one or more copper salts is used to gain shape with a metal such as iron, zinc or the like., The conditions are chosen that the finest possible distribution is achieved. The powdery or spongy one Precipitation is cleaned well. It is in the form in which it is then received however, not very plastic. Around a finely divided mass of the highest plasticity to achieve, it is subjected to a reduction. You then get masses of spongy or possibly of a powdery nature that do not easily oxidize and are very plastic.

A cold saturated one is particularly suitable for obtaining such masses Solution of copper sulfate, which has about a 3 percent addition of concentrated hydrochloric acid contains. If zinc is used in particular for precipitation, an excellent starting material is obtained for further treatment. It is best to use rolled zinc sheet.

The precipitate obtained is carefully washed out until none foreign components are more detectable. When using a hydrochloric acid additive it is sufficient to check the washing water for chlorine. When the chlorine reaction disappears the washout can be regarded as finished. The washed-out precipitate, which is generally somewhat oxidized, is now subjected to a reduction. Included care must be taken that the temperature is kept as low as possible, and in any case Do not exceed dark red heat, otherwise there is a risk that the product loses its plasticity. The primary reducing agent is hydrogen into consideration. But it can also be carbon monoxide or methyl alcohol in vapor form or also can be used as a liquid.

In order to achieve a further increase in plasticity, it can be downright desirable that the manufactured product is oxidized as early as possible in the state of origin. For this purpose, oxygen (air) can be finely divided into the liquid blow in so that they are as intimate as possible with the surface of the precipitating metal Touch comes.

The copper obtained according to the process described stands out not only because of its extraordinary plasticity, but also because of its low level Oxidizability off. One can. Get masses that knead with your fingers and let it be pressed into any shape with a little more pressure. They fill the form very completely and form uniform metallic bodies, the if the Surface is smoothed, show a high metallic luster. They are of such strength that they are suitable for the metallic connection of prepared parts made of metals or other materials can be used.

A particularly important area of application is the use as a putty, to connect metallic conductors with good conductivity and permanently with dynamo brushes.

Another application is in the manufacture of dynamo brushes, which are made of copper and coal. The best way to do this is to go by one not spongy, but powdery material, it mixes it intimately with graphite and readily presses the mixed mass thus obtained into the mold. Then you get very firm and well-conducting body. In addition to graphite, others can also be used here Metal powder are added, which come into consideration for the brush production. You can in such a way with a suitable mixture z. B. make good bronze brushes.

The plastic copper paste can also be used in many cases are used in place of solder. For example, you can use electrical lines in cable lugs Connect permanently conductive with the help of a copper mass of the type described. Particularly in places where high temperatures can occasionally occur, which can cause the tin to Such a connection is of value; furthermore everywhere there, where, for any reason, soldering of the metal parts in sleeves, grooves, etc. would be difficult to do.

Claims (1)

PATENT CLAIM: Process for the production of shaped bodies made of copper, characterized in that this is done by precipitation using iron, zinc or other metals copper precipitated from the aqueous solution of one or more copper salts with Washed out water, with a dark red heat not exceeding temperature Hydrogen is reduced again and the copper mass obtained in this way by pressure (pressing, Hammering and the like) is shaped or pressed between parts to be connected.