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Applications
Pencils
Since the 18th century graphite has been used for its supposedly most widely known application, the production of pencils. The blackening power and the crystallographically caused sliding and adhesive property of graphite are the basis for the pencil's writing properties. Graphite still remains the central raw material both in the traditional wood pencil and in the modern fine-lead pencil that requires highly sophisticated production technologies
Crucibles and Refractory Products
For millennia...
Already more than 2,000 years ago the Celts used graphite in the production of fireproof ceramics, and in today's fireproof industry graphite still plays an important role due to its high resistance to oxidation, its outstanding thermal conductivity, and its chemically inert behaviour.
Crucibles
Large flake graphite with a well pronounced crystal structure are the guarantee for the long service life and the high quality of crucibles, where graphite also reduces the formation of deposits and slag. Graphite also is used as covering material for high-quality molten metal - for example, high-purity flake graphite is used in copper production
Fireproof products
Graphite is an important component of many fireproof materials, the type of which primarily is used in the metal-production industry. Both in magnesite bricks for furnace lining, and in continuous casting gutters, or mould compounds, graphite as a highly-resistant thermal conductivity additive is a fixed part of the ceramic formulas
Brake Linings and Carbon Brushes
Brake linings
Lubricity in friction linings must not necessarily be a contradiction. With its lubricating properties, graphite modulates the braking effect of friction linings and essentially contributes to braking comfort and to noise reduction. The outstanding thermal conductivity properties of graphite also play an important role in friction linings.
Carbon brushes
As electrical sliding contacts in an electric motor, carbon brushes at the same time have to meet the highest demands concerning resistance to wear and oxidation, electric and thermal conductivity, as well as lubricity. In this connection graphite plays a central role as an important component of many carbon brush formulas.
Powder Metallurgy
Especially in the automobile industry, parts made in powdermetallurgy processes are of ever increasing importance. For the production of sintered parts, metal powders are mixed with small quantities of additives such as waxes and graphite. Under high pressure, these powder mixtures are then pressed into so-called green compacts. In this process, graphite both ensures reduced wear of the press die and internal lubrication of the powder mixture, because it allows maximum compression.
In the sintering process, where the green compacts are heated to slightly below the melting point, the material is then further compressed. Furthermore, fine graphite goes into solution in the metal and increases the mechanical strength of the workpiece.
Self-lubrication
There are special powder mixtures for self-lubricating sintered parts. These special mixtures contain coarser graphite that only goes into solution to a small extent during the sintering process. The graphite particles are incorporated into the matrix of the workpiece mostly in intact condition, and are exposed step by step during the life of the part, which allows graphite to develop its lubricating effect.
Constancy
Only a constant raw material quality and reproducible process parameters guarantee the dimensional accuracy and perfect quality of precision parts made in powder-metallurgy processes.
Batteries and Fuel Cells
Energy systems
The increasing capacity of batteries and rechargeable batteries accelerates and promotes their use in a great variety of technical applications.
Furthermore, with the approaching shift of emphasis in the energy industry from fossil to renewable energy sources, hydrogen as a source of energy, and the fuel cell as a highly-efficient energy conversion system, will become ever more important. Graphite, and especially natural graphite, is an important and efficient raw material in the production of innovative energy storage and conversion systems
Batteries
In various battery systems, such as e.g. AlMn, NiCd, or zinc-carbon cells, graphite is used as a chemically inert and highly oxidation-stable conductivity additive. In such cases the purity requirements for graphite may be as high as 99.99 % carbon, and such degrees of purity can only be produced by way of special purification processes
Li-ion/ Li-polymer cells
In state-of-the-art Li-ion or Li-polymer batteries, graphite plays an active role as an anode material into which Li ions are intercalated. This intercalation process is only possible because of the layered crystal structure of graphite
Fuel cells
In PEM fuel cells, graphite will play an important role in the future as the preferred raw material for bipolar plates. Natural graphite combines the following unique properties: high electric conductivity; graphite is chemically inert and has an extremely low permeation coefficient, is mechanically stable, and available at a favourable price. With our extensive product range we can provide suitable materials for any bipolar plate production concept. We supply graphite grades for the production of graphite foils and graphite blocks, and also for injection moulding.
Polymers
Plastics In plastics, graphite can have many functions: Conductivity additive, flame-proofing additive, IR absorber, shielding against electromagnetic radiation, internal lubricating agent, effect additive, thermal conductivity additive, etc. In many cases the combination of different effects furthermore is an additional advantage of the use of graphite. We provide optimised products for any desired effect.
Conductivity
As a result of great efforts in development work, we provide both optimised natural graphite grades that are made in conventional production processes, as well as so-called COND graphite grades that are made in a special production process. These special graphite grades have integrated conductivity links between the individual graphite particles, which minimised the electric contact resistance. Our technical brochure "Graphite for Polymers" provides you with information about this special product range, its properties and fields of application.
Graphite Dispersions
A dispersion generally is a mixture of at least two substances. A solid substance that is mixed in a liquid is referred to as a suspension. However, the term of graphite dispersion has become common usage. Graphite Dispersions are used in applications that require a uniform and fine distribution of graphite on the surface of the carrier material. Depending on each individual application, the following dispersion properties are of decisive importance: Sedimentation stability, surface tension, wetting behaviour on different surfaces, adhesive power on different surfaces, drying time, viscosity, pH-value, and ionogenity
In order to improve the dispersing effect, individual formulas apart from graphite and the dispersion agent (in most cases water) also contain protective colloids, preserving agents, and other additives.
Graphite Dispersions can be individually produced for any application
Range of Products
Graphite
Our wide range of raw material provenances and our great variety of production possibilities allow us to produce a large bandwidth of natural graphite in the most varied grain sizes, from flakes to finest powders. We are able to manufacture graphite products with a purity of > 99.99 % carbon. Our wide range of natural graphite products is supplemented by an extensive spectrum of synthetic graphite products. Vein graphite, which only occurs on Sri Lanka, is a specialty of our product range. The needle-shaped particle structure and the unique crystallinity of this graphite, for example, is important for applications that attach great importance to electric conductivity.
Expandable graphite
Expandable graphite is mostly used in plastics to give flame-retardant properties. Our product range includes expandable graphite in the most varied specifications.
Graphite Dispersions
Our flexibility also shows in the field of graphite dispersions. We both produce finished graphite dispersions and powder premixes that can be dispersed at the customer's location.
Graphite parts
We produce graphite parts in any geometric shapes, specifically to customer requirements.
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