Battery Power Sector
- Lithium-ion batteries are found everywhere today in laptops, cell phones, audio players, digital cameras, power tools and medical devices with progress continually ongoing. While the market is significant and growing, its actually about to take a big leap forward in the vehicle sector.
- There is a growing consensus that the world is moving towards a critical tipping point in the demand for electric and hybrid electric vehicles (EVs and HEVs). Given that these vehicles are powered largely by lithium-ion batteries, and that natural graphite is a key component in the anode portion of these batteries, it is widely expected that demand for graphite will increase significantly over the next ten years. To put this into perspective, the average EV or HEV will require approximately 1,000 individual battery cells per car. Each cell will contain approximately 14 grams of graphite, or about 13 new kilograms of graphite per vehicle. This is in addition to the many other items in a vehicle already using natural graphite.
- As a result, given a modest annual increase in vehicle production over the next ten to fifteen years; allowing for a reasonable conversion to EVs and HEVs; and taking into account the battery replacement processes that will occur as cars age, it is expected that annual global graphite requirements could increase as much as 500,000 tonnes per year. If you add in the current and expected export constraints from key suppliers such as China, it is completely understandable that graphite customers around the world are looking for alternate and stable suppliers such as MEGA Graphite.
- Only flake graphite is able to be enhanced to 99.9% purity used to make the requisite “spherical” graphite used in vehicle batteries. The process is expensive resulting in prices as high as $3-4,000/ton – as much as triple the price for high quality flake graphite.
Fuel Cell Sector
- Fuel cells generate electricity through chemical reactions and need to be “refueled.” Current fuel cells are designed for use in both stationary and mobile applications producing next to zero waste or noise. They offer long duty cycles with low maintenance and reliability due to a lack of moving parts. They are considerably more efficient than internal combustion devices and use significantly more graphite than lithium-ion batteries.
- Fuelcells.org states “there are many uses for fuel cells right now and all of the major automakers are working to commercialize a fuel cell car. Fuel cells are powering buses, boats, trains, planes, scooters, forklifts, even bicycles. There are fuel cell-powered vending machines, vacuum cleaners and highway road signs. Miniature fuel cells for cellular phones, laptop computers and portable electronics are on their way to market. Hospitals, credit card centers, police stations, and banks are all using fuel cells to provide emergency power to their facilities. Wastewater treatment plants and landfills are using fuel cells to convert the methane gas they produce into electricity. Telecommunications companies are installing fuel cells at cell phone, radio and 911 towers.”
- According to the United States Geological Survey, fuel cells have the potential to consume as much graphite as all other uses combined. There are a number of different types of fuel cell under development although the proton exchange membrane technology (“PEM”) is the only one that uses large quantities of graphite and could create significant demand for graphite. However, the US Department of Energy suggests that PEM cells are the most likely to be developed for use in light vehicles, buildings and smaller applications.
Nuclear Power Sector
- Natural graphite has found new uses in an advanced “pebble bed” nuclear reactor (PBR) design that uses neither rods nor cooling towers but instead inserts the radioactive uranium dioxide fuel as tiny flakes into a round graphite tennis-ball sized (pebble) shell coated in a number of chemical layers. The graphite in the pebbles is a mixture of 75% natural graphite and 25% synthetic (pyrolytic) graphite. The small uranium dioxide spheres are each coated with a layer of porous carbon, then high density pyrolytic carbon, silicon carbide, and then another layer of pyrolytic carbon. This is known as Triso fuel.
- This type of reactor is deemed to be passively safe thereby removing the need for redundant, active safety systems. Because the reactor is designed to handle high temperatures, it can cool by natural circulation and easily survive in accident scenarios. It’s high temperatures design allow higher thermal efficiencies than possible in traditional nuclear power plants (up to 50%) and have the additional feature that the gases do not dissolve contaminants or absorb neutrons as water does, so the core has less in the way of radioactive fluids.
- China has an active prototype with stated plans to construct 30 reactors by 2020 and aims to ramp up to 300 gigawatts of new reactors featuring PBRs as a significant component of the planning. The modular reactor scenario is of notable interest for smaller centers and industrial applications in remote locations. West Virginia University researchers have estimated 500 modern 100 GW PBR installed in the US by 2020 would require an estimated 400,000 tons of graphite. This projection equals the world’s current annual production of flake graphite without taking into account global demand for additional PBRs and other traditional uses for graphite.
- Natural graphite is also found in multiple other materials used in nuclear reactors including gaskets, sealants, and liners. The table below outlines some of the properties associated with nuclear graphite.
Chinese Export Sector
- China produces over 80 percent of the world’s graphite supply. Around 70% of Chinese production is fine or amorphous graphite and 30% is flake. China produce limited large flake graphite however most flake production is in the +200 mesh range (very small).
- China created a large decline in graphite prices in the 1990s by dumping product onto the market. Subsequent extraordinary growth in the Chinese steel industry which consumes a great deal of domestic graphite minimizes repetition of this occurrence. Declining quality is driving costs due to internal controls resulting in improved labor and environmental conditions.
- Most Chinese graphite mines are small and subject to seasonal closures. Depletion of surface deposits is driving the industry into higher costs as mines expand. China has implemented export licensing and applied duties and taxes. This environment is closing down marginal producers and leading to lower production which is creating global supply concerns.
High Purity Applications
Over the past decade natural graphite has been refined into products such as expanded graphite, exfoliated graphite, and graphite foil. Each of the materials has a wide range of applications in sectors such as high temperature gaskets in automotive applications, thermal management in electronics, and high strength components in aerospace products. As previously noted, it is graphene that is being called the Mother of All Graphite’s these days. Scientists and companies are only just beginning to understand its full range of capabilities whether it be solar cells, liquid crystal displays, or semiconductors. Whatever the application, it is widely seen as a natural graphite growth sector for many years to come.
Semiconductor Materials and Quartz
Semiconductor technology demands constant innovation and ultrahigh-purity materials from suppliers. Products made from high-purity fine-grain graphite meet these requirements. Typical examples are the development of materials for wafer production processes, as well as coatings that enhance the purity of the next semiconductor generation while extending our materials’ service life at the same time. The following are products using graphite in semiconductor manufacturing:
- Electrodes and heating elements for manufacturing high purity quartz glass products
- Heaters and shields for manufacturing optical fibers
- Blanks and graphite electrodes for polycrystalline silicon deposition
- Components made of high purity graphite, carbon/carbon, soft and rigid felt for crystal growing of silicon, germanium and III/IV composites (e.g. susceptors, heaters, heat shields, current connecting parts)
- Slicing beams made of carbon and graphite for cutting monocrystal rods
- Graphite boats for zone refining of semiconductor materials
- Graphite boats for reduction heating of germanium oxide
- Graphite and C/C crucibles and boats for melting high purity metals or semiconductor materials
- Brushes, Anodes, Cathodes, Current Collectors, Sliding Contacts, EDM Electrodes, Resistors, Brazing Tips, Heaters, Seed Holders, Susceptors, Wafer Carriers, Purified Components, Heaters, Crucibles, Seed Rods, Bolts, Power Connectors, Diffusion plates
Thermal Management Solutions
- Heat Sinks
- Heat spreader materials
- Heat sinks for phone docking stations
Natural graphite is an excellent conductor of electricity and heat. The strength of its crystalline molecular structure also allows it to withstand extremely high temperatures, and it is not affected by a majority of reagents and acids. These properties are ideal for use in a wide range of traditional industrial applications as follows:
Casting Molds, Dies and Tooling
The most common applications for graphite within this area are in the manufacture of crucibles and molds, graphite heating elements, heat treating furnace fixturing, chemical processing equipment, molten metal extrusion, pressure casting, vertical and horizontal continuous casting, centrifugal casting, graphite susceptors, heat shields and furnace linings.
Chemical and Electro-Chemical Process Technology
Plant availability combined with greater operational reliability and lower emission rates are of key importance to our customers. Aggressive and volatile media in chemical processes rely on corrosion resistant graphite materials to ensure that these manufacturing operations are safe and reliable. Here are a few of the products that use graphite in chemical processes:
- Vessels and components (e.g. support grids) made of graphite for chemical plants
- Graphite blanks for manufacturing heat exchangers
- Graphite spreaders in distillation columns
- Vessels and Reactors, Bushings & Bearings, Packing Rings & Seals, Roller Guides, Valves, Rotors & Vanes
- Graphite anodes and cathodes for chlorine-alkali electrolysis
- Electrodes for chemical separation processes
- Graphite anodes and cathodes for electrolysis of lithium, sodium, magnesium and fluorine
- Anodes for corrosion protection of pipe lines
Graphite dispersions are used in applications that require a uniform and fine distribution of graphite on the surface of a carrier material. Depending on the individual application, properties such as sedimentation stability, surface tension, wetting behavior and adhesive power on different surfaces, drying time, viscosity, pH value and ionogenity all play varying roles of importance. In order to improve dispersing effects, formulations may also contain protective colloids, preserving agents, and other additives. The following are applications for graphite dispersion’s:
- Hot metal forming
- Coating systems
- Matrix coating
- Glass, Rubber, Can, Seed, Raiway and Switch, and Power Line coating
Ferrous Metallurgy & Continuous Casting Technology
The use of graphite in ferrous metallurgy and continuous casting has been one of the traditional areas of application. The following are just a few of the places graphite is used:
- Graphite Trays & Boats, Crucibles, Fluxing (Degassing) Tubes, Molds & Dies, Furnace Parts, Foundry Accessories, Canisters & Aluminum, Extrusion Boards Anodes, Crucibles, Ingot Molds, Custom Molds.
- Large sized blanks and graphite dies for continuous casting of stainless steel and grey iron.
- Large sized blanks and molds for pressure casting, continuous casting, centrifugal casting and wheel casting; graphite plates for cooling of complex grey iron shapes.
Glass and Ceramics Industry
Graphite is used to produce precisely machined components used in the continuous production of plate glass in float glass systems. It is an ideal material given the high temperatures and heavy loads that characterize the production processes in glass manufacturing. The following are common products using graphite in the glass and ceramics manufacturing industries:
- Tin bath linings, cooling equipment and top rollers, guidance systems for the tin bath, gas guide systems and insulation felts for the production of float glass
- Scoops for distribution of glass drops, molds and various accessory parts made of carbon, graphite or carbon composites for container glass production
- Graphite dies and plungers for hot pressing processes for the production of e.g. boron nitride products
- Furnace components for manufacturing high performance ceramics
Heat Treating Industries
High-temperature processes such as the heat treatment of metals under vacuum or inert gas rely on graphite in numerous situations. In these environments materials must be suitable for temperatures up to 2,200°C, exhibit high creep resistance, and be chemically inert. The following are typical examples of materials using graphite in heat-treating:
- Flexible and rigid felt for thermal insulation
- Flexible graphite foils and CFC for heat shields
- Laminated sheets for electrical heating elements
- Dies and support plates for brazing processes
- Charging systems and furnace equipment made of graphite for hardening, sintering, brazing and coating processes
- Molds made of graphite for manufacturing aerospace components
- Boats, crucibles and other containers, liners, heaters, heating tubes for cemented carbide production
Owing to its excellent properties, graphite is also used for the manufacture of the rotating anodes used in X-ray tubes. The high quality standard of the graphite and consistency in its mechanical properties make us a reliable supplier.
- Graphite discs as heat sinks for X-ray anodes
- Dental crucibles for melting precious metal alloys
- Operating materials for manufacturing of mechanical heart valves
A primary application for graphite in this area is the aluminum production process. The following are common products that rely on graphite in this area:
- Large sized blanks, graphite dies and plates for continuous casting of non-ferrous and precious metals
- Large sized crucibles and heating systems for melting and holding processes
- Fluxing tubes, gas distribution and gas injection systems for purification of aluminum melts; plates and belts for run-out tables for aluminum profile extrusion; crucibles and boats for aluminum casting; electrodes for aluminum surface cleaning
- Electrical contacts, dies and support plates for brazing processes
- Crucibles for gas analysis of metals
- Aluminum casting rings made of graphite
Refractories are heat-resistant materials that constitute the linings for high-temperature furnaces and reactors and other processing units. These can range from simple magnesia-carbon bricks to complex geometric shapes used to line boilers and furnaces of all types – reactors, ladles, stills, kilns, etc. – and are required for heating applications above 538°C. In addition to being resistant to thermal stress and other physical phenomena induced by heat, refractories must also withstand physical wear and corrosion by chemical agents. Depending on the application, refractories must resist chemical attack; withstand molten metal and slag erosion, thermal shock, physical impact, catalytic heat, and similar adverse conditions.
Since the various ingredients of refractories impart a variety of performance characteristics and properties, many refractories have been developed for specific purposes. Specifically, refractories are produced from natural and synthetic materials, usually non-metallic, or combinations of compounds and minerals such as alumina, fireclays, bauxite, chromite, dolomite, magnesia, graphite, and zirconia. These refractories are available in a wide variety of shapes and forms roughly divided into brick or fired shapes and specialties or monolithic refractories. Refractory linings are made from these bricks and shapes, or from specialties such as plastics, castables, gunning mixes or ramming mixes, or from a combination of both.
Flake graphite, preferably high-purity, coarse-flake grades, provides good oxidation and corrosion resistance and the orientation of the flakes improves structural strength in various carbon-based castable refractories like ramming and gunning mixes and shaped refractories such as resin-bonded magnesia-carbon (mag-carbon) brick. Flake graphite is also used in alumina-graphite continuous casting ware, zirconia-graphite refractories for continuous casting, and silicon carbide-graphite refractories. The following is a brief discussion of various refractory types using natural graphite:
- Magnesia-carbon (mag-carbon or mag-graphite) refractories – developed in the 1970s, mag-carbon refractories consist of fused magnesia and crystalline flake graphite bonded with synthetic resin. Graphite contents vary between 15 – 25% with small flake sizes of between 0.15 to 0.71mm and carbon contents of 87 to 90% being preferred. In fact, the graphite grade has the most important influence on brick characteristics together with ash content, particle size and shape. Magnesia-carbon refractories are preferred in high temperature environments where corrosion is a problem, in particular in basic oxygen steel converters, electric arc furnaces, and slag zones in steel lines, ladles, and nozzles.
In basic oxygen steel converters, mag-carbon bricks are now the standard lining materials since they can withstand a much greater number of heating cycles than traditional pitch-bonded dolomite and fired magnesia dolomite bricks. They consequently need replacement much less often. In electric arc furnaces, mag-carbon bricks have also largely replaced the traditional mag-chrome bricks, particularly in slag zones. In the same way, mag-carbon refractories are increasingly used in steel ladle slag zones, replacing the more traditional alumina and zircon refractory linings. They can cope with the higher temperatures and dwelling times in the ladle more easily. This is where refining and trimming of the steel is now normally carried out.
- Alumina-graphite refractories – these refractories have excellent resistance to thermal shock and corrosion attack which is essential in continuous casting, shrouding tubes of slab and bloom casters, submerged entry nozzles, and torpedo ladles. The use of graphite in these refractories, which have to withstand contact with molten steel at 1,600°C, improves their thermal shock and corrosion resistance. High purity graphite with a large flake size is preferred.
- Zirconia-graphite refractories – the lifespan of alumina-graphite refractories is extended with a coating of zirconia or zirconia-graphite. A fused zirconia-graphite coating combines the extreme corrosion resistance of stabilised zirconia with the thermal shock and conductivity properties of flake graphite. However, the high cost of zircon has encouraged some refractory manufacturers to use spinel instead.
- Silicon carbide-graphite refractories – flake graphite is added to silicon carbide to enhance its thermal conductivity, shock resistance, and resistance to wetting by molten steel. These refractories, which commonly contain 3% carbon, have become increasingly popular in the manufacture of heater tubes and immersed pyrometer sheaths in zinc and aluminium applications.
Recent advances in the development of graphite-based products have opened up multiple new opportunities and markets for natural graphite suppliers. Research around the world is moving ahead rapidly on graphene for example which can be prepared as a flat single layer of carbon atoms which can transport electrons at remarkable speeds, making it a promising material for electronic devices. Solar cells stand to be one of the biggest beneficiaries of these new products, particularly as efforts are made to expensive materials such silicon and indium.
The production of silicon and solar wafers and cells is also using high-purity fine graphite and carbon-reinforced fibers, and in the manufacture of solar silicon pre-products, the crucibles, boats and various other molds and heating systems used in different processes are made from graphite or carbon-reinforced fibres, sometimes in very large dimensions. Finally, researchers at Arizona State University have also reported remarkable results using graphite nanoparticles as a substitute for silicon in solar panels. Adding these particles into heat-transfer mediums within the cells can dramatically boost the efficiency of the cells, which is one of the key challenges for increased solar adoption. Adding this graphite compound could increase the inefficiencies by greater than 10-20 percent. Part of this effect is caused by the fact that graphite is black, and therefore absorbs light very efficiently.
Over the past decade natural graphite has been refined into products such as expanded graphite, exfoliated graphite, and graphite foil. Each of these materials has a wide range of applications in sectors such as semiconductor manufacturing, high-grade electronic components, thermal management solutions in electronics, power generation management and high strength components in aerospace products. In addition, scientists and companies are just beginning to understand the development of important new materials such as Graphene, often called the Mother of All Graphites With applications in fast-growing areas such as solar cells, integrated circuits, touch screens and liquid crystal displays, the worldwide demand for natural graphite and its spinoff materials is only expected to continue increasing over the next decade. The following is a brief discussion of a few of the high-purity applications for natural graphite.
Graphite is an excellent material for aircraft turbine engine mainshaft seals. The mainshaft in a turbine engine rotates at very high speeds and operates in an environment of changing high temperature conditions. Mainshaft bearing compartment seals are used to protect rotor support bearings from hot gases flowing through the engine and to prevent the loss of lubricant in the bearing compartments. Because graphite is light and strong, and because it can withstand extreme temperatures, it is in demand for surface tiles on space shuttles, in nuclear technology as a neutron moderator, and under extreme cold conditions such as in cryogenic applications.
High Grade Electronic Components
- SiC-coated barrel, pancake and single wafer susceptors for ASM, Gemini and LPE and various other OEMs silicon epitaxy reactors
- Graphite boats for liquid phase epitaxy (LPE)
- SiC-coated graphite susceptors for various MOCVD processes
- Single wafer susceptors for various processes, e.g. rapid therm process (RTP), low pressure chemical vapor deposition (LPCVD), etc.
- Electrodes, ion sources (arc chambers) and shields for ion implantation
- Electrodes (grids) for plasma etching
- Liners (crucibles) for electron beam evaporation (EBE)
- Brazing and glass to metal sealing jigs
Power Generation and Management
- Graphite melting containers, casting dies and CZ growing parts for the production of solar grade silicon (CZ, Bridgeman and others)
- Anode material for rechargeable lithium-ion batteries
- Nozzles for high voltage switchgear