Copper powder: production, purpose and application

2024 Author: Howard Calhoun | [email protected]. Last modified: 2024-01-07 20:55

Powders from various kinds of metals have been used by man since ancient times. For example, crushed gold and silver were once used to decorate pottery. Also, such materials were used in painting. At present, copper powder has found wide application in industry.

What is

In most cases, this powder is 99.5% copper. Also, its composition may include a small amount of various kinds of impurities of other metals. Most often it is lead, tin and iron. In another way, such material is also called copper powder.

How it is made

The enterprises of the chemical industry of non-ferrous metallurgy are engaged in the manufacture of this product. There are two main ways to produce copper powder:

• mechanical;
• physical and chemical.

When using the first technology, a powder with practically unchanged chemical composition is obtained. The second method is considered somewhat more complicated. When it is applied, the source material significantly changesinitial properties.

Mechanical production method

Copper in this case for the manufacture of powder can be used both solid and molten. This product itself is obtained by mechanical action on it. For hard material, this can be grinding, abrasion, grinding, crushing.

Molten copper is turned into powder by crushing its stream with gas or water. This method allows you to get a fairly pure homogeneous product. In addition, using this technique, it is possible to produce a powder with a given number of particles of a certain size and shape.

Physico-chemical method

When using this technology, raw materials undergo deep physical and chemical transformations. Most often, this is a process of dissolution followed by recovery, called cementation. Usually, when using this technique, copper powder is deposited using less valuable metals, such as iron.

In the autoclave production method, Cu is reduced from a solution of its s alt with hydrogen. Such a reaction takes place at the enterprise at the same time at elevated temperatures and pressures.

The hydroelectrometallurgical method is also often used to produce copper powder. In this case, the product is obtained by electrolysis of aqueous solutions of copper sulfate using soluble anodes (under certain conditions). This procedure is carried out in bunker-type baths with lower powder discharge. The surfaces of such containers are lined with acid-resistantmaterials.

Main Applications

The powder produced by modern industry is in most cases non-toxic, non-radioactive, non-explosive and even non-flammable. Therefore, the scope of its application is quite wide. Most often, this non-ferrous metallurgy product is used in powder metallurgy.

Also, this material is widely used:

• in the paint industry;
• in the chemical industry;
• in conventional metallurgy;
• in the electric coal industry;
• in microelectronics;
• in the automotive industry;
• in the aviation industry;
• in nanotechnology;
• in instrumentation.

In the manufacture of various kinds of paints, copper powder is used as a pigment. In the metallurgical industry, it is used for spraying processes. This material is also used in the production of carbon electrodes.

In the automotive industry, metal powder is used, for example, in the manufacture of tires, as well as anti-wear parts.

In powder metallurgy, such material is used primarily for the production of various kinds of sintered products. It can be, for example, all kinds of rings, bushings, etc.

Classification of powders

Modern industry produces several grades of copper powder. For realmoment on sale you can meet products of this type:

• MA and PM are unstable.
• PMS-K - stabilized caulking.
• PMS-A, PMS-11, PMS-1, PMS-B - conventional stabilized.
• PMU - ultrafine copper powder.
• PMR, PMVA - highly dispersed product.

In the manufacture of powder from copper, like any other material, enterprises in Russia, of course, must comply with certain standards and norms.

GOST 4960 for electrolytic powders: impurities

The main manufacturer of such products in our country at the moment is Uralelectromed JSC. Of course, electrolytic copper powders are also produced at this plant in strict compliance with the standards stipulated by state standards. GOST 4960 regulates the release of such products in Russia today. This document, among other things, regulates the amount of impurities in the material of a particular grade.

For example, copper PMS-B powder should contain:

• iron - no more than 0.018%;
• arsenic - 0.003%;
• lead - 0.05%;
• oxygen - 0.10%;
• compounds of sulfuric acid metals (converted to sulfate ion) - 0.01%;
• calcined residue when used to treat nitric acid - 0.04%.

Exactly the same requirements are observed in the production of copper powder PMS-1, 11, A(excluding the percentage of oxygen included).

Product of PMS-N and PMS-K brands should contain no more than:

• iron - 0.06%;
• lead - 0.05%;
• antimony - 0.005%;
• arsenic - 0.003%;
• sulphuric compounds - 0.01%;
• oxygen - 0.5%;
• calcined residue - 0.05%.

The mass fraction of copper, as already mentioned, according to the standards, in all grades of electrolytic powder should be at least 99.5%.

Other features

According to GOST 4960, enterprises, among other things, must comply with the granulometric composition of their products, as well as its bulk density. Both of these indicators are determined by special tables.

The bulk density of copper powders should be:

• PMS-B - 2.4-2.7.
• PMS-K - 2.5-3.5.
• 1 - 1.25-2.0.
• A - 1.3-1.5.
• PMS-11 - 1.25-1.9.

GOST also regulates, of course, other parameters of powders:

• for grade PMS-V, the raw pressing strength should not be less than 60 kgf/cm2;
• PMS-B powder should have a minimum flow of 36 s.

In addition, PMS-A brand product:

• should differ in specific surface areaparticles 1000 to 1700 cm/g;
• should not have electrical resistivity higher than 20 10 ohm m;
• should contain particles with a diameter of no more than 10 microns from 25 to 60%.

The presence of lumps or any foreign inclusions in the copper powder of PMU, PMS, etc., according to the rules of GOST, is not allowed. The shape of all particles of such a product must be dendritic.

What other regulations govern

The main document regulating the production of copper powders is GOST 4960. However, in some cases, in the manufacture of such material, manufacturers may be guided by other regulatory documents.

For example, ultrafine PMU powder is often manufactured in accordance with the rules of TU 1793-001-50316079-2004. According to this document, such a product must have a chemical purity of at least 99.999%. Its isotopic purity should be Cu65-30, 91+Cu63-69, 09.

Regulates specifications and shape of PMU powder particles. According to this document, it should be spherical for them. In this case, the powder itself should not have a layered structure. Of course, in it, among other things, there should be no foreign inclusions.

Packaging

Copper powder for industrial use is supplied to the market, most often in special steel drums lined with a plastic bag. The volume of such containers is usually 25.45 dm3. To protect the product during its transportation and storageplastic bags are double tied together.

In some cases, copper powder PMS-1, A, B, etc., can be supplied to the market in soft special polypropylene containers. Polyethylene liners are also provided in such containers. This type of packaging, however, may only be used by the manufacturer upon prior agreement with the consumer.

Copper powder belongs to the fourth hazard class. Fluctuations in temperature or high humidity do not have any particular negative effect on it. Therefore, it is allowed to transport such material by any means of transport.