Tantalate additive for aluminosilicate glass as well as preparation method and application of tantalate additive

The invention discloses a tantalate additive for aluminosilicate glass as well as a preparation method and application of the tantalate additive. The tantalate additive is mainly composed of one or two of AlTaO4 or CrTaO4 and the balance of inevitable impurities, and the content of the impurities is lower than 10 wt%. The preparation method of the tantalate additive comprises the following steps: mixing Al2O3 and/or Cr2O3 with Ta2O5 to obtain mixed powder, dissolving the mixed powder with absolute ethyl alcohol, and then sequentially carrying out ball milling, drying, sintering and crushing to obtain the tantalate additive. According to the invention, high-field-intensity tantalate ions are used to improve the viscosity of alumina-silica glass and increase the wetting angles of a glass phase, a corundum phase and a baddeleyite phase. Meanwhile, compared with other additives, the high-temperature-resistant lubricating oil has a higher hemispherical point temperature. The preparation method has the characterist