Development Status Of Zirconia Industry

At normal temperature, zirconia can only be a monoclinic phase. When calcined with zirconium salt, a stable tetragonal phase appears when it reaches 650 °C. When it continues to rise, the tetragonal phase gradually changes to a monoclinic phase, and then continues to heat up to 830 °C. Zirconium oxide begins to transform into a tetragonal phase. When it reaches 1170 °C, it completely transforms into a tetragonal phase. When the temperature rises to 2370 °C, it turns into a cubic phase. When the temperature decreases, it gradually transforms into a tetragonal phase. When it reaches room temperature, it becomes stable. Single oblique phase. The transition of monoclinic zirconium dioxide at 830-1200 °C is complicated and hysteresis occurs. It is this hysteresis that provides an important property for zirconia applications in ceramics and refractory applications. During the transformation process, a corresponding volume change will occur. When the temperature rises, the volume will shrink by 5% when the monoclinic phase changes to the tetragonal phase, and the volume will expand when the temperature decreases from the tetragonal phase to the monoclinic phase. 8%, the existence of three phase structures, the thermal expansion is not the same. Since the Australian scholar K.C.Ganvil first proposed the use of the volume effect produced by the zirconia ZrO2 phase transition to achieve a new concept of toughening ceramics in 1975, the study of zirconia has become extremely active. Especially in 1983, Tosoh was the first successful industrialized nano-composite zirconia. Due to its excellent physical properties and chemical properties, countries have increased their investment in the development of nano-composite zirconia products, and their applications have gradually expanded to structural materials. Various fields such as functional materials are currently being widely used in various industries. (1) Development status and trend of global zirconium industry Zircon sand is mainly produced in Australia, South Africa, the United States, and other places in Hainan Province and Guangdong Province. According to the 2009 International Zirconium Conference, Australia and South Africa account for 91% of global exports in terms of supply of zircon sand. China is the largest consumer in terms of demand. Developed countries are currently not involved in the production and processing of primary zirconium products. 90% of zirconia is produced and processed in China, of which more than 85% are exported, mainly exported to the United States and Japan, followed by Europe, for ceramics, zirconia products and nuclear sponges. Production of zirconium. In 2003-2008, the annual growth rate of the global zirconium industry reached 9.3%. In 2009, due to the financial crisis, the market demand for zirconia industry shrank sharply. However, it is expected that the average annual growth rate will stabilize at around 4.4% after the economic recovery until 2020. . (2) Development status and trend of China's zirconium industry Since the beginning of the 21st century, the demand for infrastructure, real estate and home decoration industries has continued to flourish, leading to a sharp rise in the use of zirconium products in the ceramic industry. The upstream material consumed by the ceramic industry is chlorine. Zirconia, zirconium silicate. In addition, with the acceleration of China's residents' consumption upgrading process, zirconium-containing special ceramics occupy an important position in the application of high-tech materials such as fuel cells, advanced special ceramics, optical communication devices, and oxidation sensors, and zirconia structural ceramics The superior physical properties have been widely promoted in the civilian fields such as knives and watches. In addition, it has been widely used as an important new material in the industrial field in the production of valves, oil drilling cylinder liners and other components. . Since 2003, with the increasing demand for zirconium products, China's zirconium industry capacity has expanded significantly. After the financial crisis in 2009, the demand for zirconium products has dropped sharply. The two factors have caused the zirconium market to be in a downturn. In 2010, the zirconium industry has fallen into a trough. Due to the increasing demand for end-use industries such as domestic ceramics, zirconium gemstones, and automobile exhaust gas purification catalysts, the output of zirconium oxychloride, composite zirconia, zirconium carbonate and other zirconia deep-processed products will be improved compared with 2012, which also drives oxygen. The domestic demand for zirconium chloride has rebounded.