Zirconium dioxide (chemical formula: ZrO2) is the main oxide of zirconium. It is usually a white, odorless and tasteless crystal, and it is insoluble in water, hydrochloric acid and dilute sulfuric acid. Usually contains a small amount of hafnium dioxide. The chemical properties are inactive, and the properties of high melting point, high resistivity, high refractive index and low thermal expansion coefficient make it an important high-temperature resistant material, ceramic insulating material and ceramic sunscreen. It is also the main raw material for artificial drills. The gap is approximately 5-7eV. Used in the production of metal zirconium and zirconium compounds, refractory bricks and crucibles, high-frequency ceramics, abrasive materials, ceramic pigments and zirconates, etc.
The definition of zirconia still needs a certain material science basis to explain. It refers to a crystal composed of only a few thousand or tens of thousands of unit cells juxtaposed to each crystal grain. From the direction of a crystal axis, this crystal only repeats about dozens of cycles. Of course, this explanation is somewhat confusing, but the characteristics of microcrystalline ceramics are still good, with high thermal conductivity and thermal expansion coefficient close to zero, no water absorption, good insulation performance, compact and uniform structure, impact resistance, wear resistance and corrosion resistance And other excellent performance. Simply put, it is resistant to falling, abrasion, and does not affect heat dissipation and aesthetics.
As far as we know, zirconia ceramics (raw material: non-metallic minerals) have the characteristics of wear resistance, high-temperature resistance and non-conductivity. However, if the piezoelectric zirconia ceramic rod is used improperly under high temperature and high pressure, it will cause certain damage to the ceramic rod. Mayang teaches everyone how to use piezoelectric zirconia ceramic rods correctly.
After the piezoelectric zirconia ceramic rod is heated in the air, a dense zirconia film is formed on its surface, which becomes an anti-oxidation (anti-oxidation free radical) protective film, which can prolong its service life.
The production of zirconia ceramics requires the preparation of powders with high purity, good dispersibility, ultra-fine particles and narrow particle size distribution. The zirconia method has many methods for preparing ultrafine powders. The purification of zirconia mainly includes chlorination and thermal decomposition, alkali metal oxidation decomposition, lime melting, plasma arc, precipitation, colloid, hydrolysis and spray pyrolysis. The repairman of the auxiliary nozzle of the air-jet loom needs daily maintenance of the electric oil pump, centralized oil supply, main motor heat dissipation part, open cam box input shaft, electromagnetic brake, weft finder, scissors, edging, side support and yarn grabbing.
The higher the current flow applied to the ceramic rod, the higher the surface temperature of the ceramic rod. Blue zirconia ceramics (raw material: non-metallic minerals) have a shorter service life and higher service temperature. Therefore, when the furnace temperature exceeds 1600°C, the oxidation speed will increase and the service life will be shortened. When using, be careful not to make the surface temperature of the ceramic rod too high.
During use, the resistance gradually increases due to the oxidation of the rod. In order to keep the furnace temperature normal, the applied voltage should be increased. When the voltage rises to the maximum limit of the transformer (air pressure variable), it still cannot meet the requirements. Therefore, before continuing to use, the furnace should be shut down and the connecting rod connection method should be changed.
When the new furnace starts to send power, the voltage should be gradually increased to prevent rod breakage. Generally speaking, it is best to start with 1/2 of the rated voltage, and then gradually increase the voltage when everything is normal. New furnaces or electric furnaces that have not been used for a long time must be baked before use. When baking, use old rods or other heat sources as much as possible.
Thin ceramic rods are strictly prohibited from overloading. If it is found that the rod is broken or unevenly heated for some reason, and the part is incandescent or dark red, it means that the rod body is inconsistent with age and the resistance of each section is too different. The furnace should be shut down for repair and replacement. Pay attention to moisture-proof during storage. The production of zirconia ceramics requires the preparation of powders with high purity, good dispersibility, ultrafine particles and narrow particle size distribution. The zirconia method has many methods for preparing ultrafine powders. The purification of zirconia mainly includes chlorination and thermal decomposition, alkali metal oxidation decomposition, lime melting, plasma arc, precipitation, colloid, hydrolysis and spray pyrolysis. If it is found that the aluminum sprayed part of the rod end has deteriorated and deliquescence, the aluminum can be sprayed again after surface treatment. If there is no aluminum spray condition, you can wrap several layers of aluminum foil in the aluminum spray section for repeated use.
