Due to the high heat in the motor and the support in the high speed locomotive, the main shaft components should be provided with an effective cooling system. The in-line asynchronous motor is mainly used in the electric spindle, and the rotation frequency can be adjusted within a large range when the power is constant. In some cases, special synchronous motors can also be used. Although they are more expensive than asynchronous motors, they generate less heat, ensure higher precision of the spindle components, and have a larger rotation frequency. Output torque. In order to adjust the rotational frequency of the electro-spindle, a vector control digital system equipped with an axis orientation device can be used. The electric spindle of the HF series is equipped with ceramic bearings, such as the HF170.2A/Z type electric spindle. It is equipped with ceramic bearings with diameters of 65mm and 55mm (the runout is less than 3m, the axial stiffness is 230N/m, and the radial stiffness is 270N). /m). The special asynchronous motor can guarantee the minimum loss when the output power ratio is 0.45kV/kg per kilogram, and has a large output torque when the rotation frequency is low. The thermal effect protection device inside the machine is cooled by the thermal varistor and water. System composition; control of the motor to ensure the positioning of the spindle when it stops. There are two options for the lubrication of the electric spindle: one is a plastic lubrication material that is loaded into the support at one time, which can be used throughout the life (nmax=16000r/min); the other is a one-time loading of oil and gas lubrication material for It is used throughout the life period (nmax=24000r/min; the acceleration time is 0.6s when the speed reaches 8000r/min). (Finish)
Zirconium Diboride (ZrB2) is a highly covalent refractory ceramic material with a hexagonal crystal structure. Zirconium Diboride Tech Grade is an ultra high temperature ceramic (UHTC) with a melting point of 3246 °C. This along with its relatively low density of ~6.09 g/cm3 (measured density may be higher due to hafnium impurities) and good high temperature strength makes it a candidate for high temperature aerospace applications such as hypersonic flight or rocket propulsion systems. It is an unusual ceramic, having relatively high thermal and electrical conductivities, properties it shares with isostructural titanium diboride and hafnium diboride.
Zirconium Diboride Powder parts are usually hot pressed (pressure applied to the heated powder) and then machined to shape. Sintering of ZrB2 is hindered by the material's covalent nature and presence of surface oxides which increase grain coarsening before densification during sintering. Pressureless Sodium Hexametaphosphate sintering of Zirconium Boride Raw Material is possible with sintering additives such as Boron Carbide and carbon which react Titanium Dioxide with the surface oxides to increase the driving force for sintering but mechanical properties are degraded compared to hot pressed ZrB2.
Zirconium Diboride,Zirconium Diboride Powder,Zirconium Diboride Tech Grade,Zirconium Boride Raw Material HENAN LIHAO CHEM PLANT LIMITED , https://www.lihaochemicals.com
March 17, 2023