Uses and applications of cobalt

At present, the traditional fields of cobalt consumption and application mainly include battery materials, super heat-resistant alloy, tool steel, hard alloy, magnetic materials; Cobalt consumed in compound form is mainly used as catalyst, desiccant, reagent, pigment and dye. Cobalt-60 is a widely used radioactive material and is widely used in biochemistry for activation analysis. It is used for tracer research in electroplating, corrosion and catalysis. It is used in medicine for radiological examination and treatment.

Magnetic material

Cobalt is one of the few metals that is magnetized once and retains its magnetism. The temperature at which magnetism is lost under heat is called the Curie point. The Curie point of iron is 769℃, that of nickel is 358℃, and that of cobalt is 1150℃. The coercive force of magnetic steel containing 60% cobalt is 2.5 times higher than that of ordinary magnetic steel. General magnetic steel loses almost one-third of its magnetism under vibration, while cobalt steel loses only 2%-3.5% of its magnetism. Because of its superior magnetic properties, cobalt is widely used in the manufacture of high performance magnetic materials.

Magnetic material is an important functional material, which plays a very important role in electronic industry and high-tech field. The application of cobalt in the field of magnetic materials is as follows: 70% is used in Alnico permanent magnet alloy, 20% is used in Smco alloy, 10% is used in other rare earth permanent magnet materials. In recent years, not only the output of magnetic materials has increased a lot, but also the structure of the magnet market has changed a lot. Worldwide, the output of Al-nickel-co magnets has been on the decline. However, the large-scale power grid reconstruction in recent years has kept the output of Al-nickel-co magnets at about 2,000 tons, while the output of cobalt-coating alloy has been increasing year by year.

Hard alloy and super alloy

The tool steel containing a certain amount of cobalt can significantly improve the wear resistance and machinability of steel. Cobalt combines other metal carbide grains in the alloy composition together, making the alloy have higher toughness and reduce the impact sensitivity. This alloy is fused on the surface of parts, and the life of parts can be increased by 3-7 times. The Stearite carbide containing more than 50% cobalt will not lose its original hardness even if heated to 1000℃.

When the temperature is above 1038℃, the superiority of cobalt-base alloy is obvious. It is especially suitable for the production of high efficiency and high temperature engine and steam turbine, so cobalt-base alloy is widely used in aerospace and modern military fields. The use of cobalt-based alloys containing 20%-27% Cr in the structural materials of aeroturbine engines can achieve high oxidation resistance without the use of any protective coating. Thermal medium turbine engines can run continuously for more than a year without maintenance.

Battery material

Nearly 40% of cobalt consumption is currently used in rechargeable battery materials, such as lithium cobaltate for lithium-ion batteries and cobaltous oxide for nickel-metal hydride batteries.

The most important use of cobalt is used in lithium batteries. One of the cores of lithium ion batteries is its cathode material, which uses lithium cobaltate (LiCoO2). Lithium cobaltate is a solid electrolyte with high energy density and high environmental safety. The advantages of lithium batteries are wide voltage range, high energy density, and environmental protection (compared with Ni-Cd and Ni-Mn).