Applications of high purity alumina
1、lithium battery diaphragm
With the increasing capacity of lithium-ion rechargeable batteries, their internal energy accumulation is getting bigger and bigger, and the internal temperature will increase, if the temperature is too high, the diaphragm will be melted and cause a short circuit. As high-purity nano-alumina has insulation, heat insulation, high temperature resistance and other characteristics, so it can be used in the coating of lithium batteries, lithium battery diaphragm coated with a layer of nano-alumina coating, can avoid short circuit between electrodes, improve the safety of lithium battery use. In addition, the application of high-purity nano-alumina to surface coat materials such as lithium cobaltate, lithium manganate, lithium titanate and lithium iron phosphate can also significantly reduce the interfacial impedance, provide additional electron transport tunnels and effectively prevent electrolyte erosion of the electrodes, in addition to accommodating the volume change of the particles during Li+ deembedding and preventing damage to the electrode structure.
2、Fine ceramics
Because high-purity ultra-fine alumina has a fine structure, uniform organization, specific grain boundary structure, high-temperature stability and good processing properties, insulation and heat resistance and can be compounded with a variety of materials and other characteristics, with its raw materials made of fine ceramics are widely used. The use of its wear resistance and dimensional stability, can be made of ceramic tools, ball mill body, crushers and other fragile parts in the crushing device and forming machinery, tools, measuring tools, shaft tiles, etc.; use of its wear resistance, surface smoothness and corrosion resistance, can be made of mechanical seals, pulleys and valves in the chemical industry, flow meters, injection heads, etc.; use of its stability can be made of precision filtration membrane, peak nest-shaped ceramic parts, etc.; use of its insulation can be The manufacture of ceramic multilayer board, electric spark plug, etc.
3、Integrated circuit field
In the field of integrated circuits, in addition to ceramic substrates, high purity alumina high-end applications and integrated circuit equipment with precision parts, such ceramics compared to the general fine ceramic performance requirements are more stringent.
4、Rare-earth phosphor field
Rare earth phosphors are commonly used as light emitting materials. Rare-earth phosphor consists of an activator and a matrix, the former is a rare-earth element, the latter is an oxide or salt. In industry, high temperature solid phase synthesis is the main production method for rare earth phosphors, and for aluminate based products, high purity alumina is required.
5、Catalyst carrier field
High purity alumina can be used as a catalyst carrier and is widely used in waste gas purification, such as chemical industry, exhaust gas treatment, flue gas purification, etc.
6、Medical material field
The ceramic matrix made of high-purity alumina as raw material has the advantages of greater strength and low friction coefficient, and under basic physiological conditions there is basically no corrosion phenomenon, with good structural compatibility, so that the gap in the bio-ceramic grows into a number of coherent tissues, improving the strength of the combination of ceramic and body, so that the matrix is now widely used in clinical practice, can be used as artificial bones, joints, dental root implants The ceramic substrate is widely used in clinical practice as artificial bones, joints, dental implants, etc.
7、Sapphire substrate field
The intact crystalline structure of high-purity alumina gives it excellent transmittance and stable performance at high temperatures, and can be used to grow single-crystal sapphire, which can be used to make semiconductors and thin film substrates. High purity alumina for sapphire preparation requires high purity and very low moisture content in the raw material, the presence of water can lead to oxidation in molybdenum crucibles when melted at temperatures above 2000°C. In addition, high-purity ɑ-Al2O3 does not stick to each other and cause clogging of the vessel. Monocrystalline sapphire technology is becoming increasingly sophisticated and the need for monocrystalline sapphire is increasing in all major fields.
