SINTERED AND DOPED PRODUCT BASED ON ZIRCON + NB2O5 OR TA2O5
Sintered product produced from a starting charge containing 75 to 99% zircon, and having the following average chemical composition by weight, the percentages by weight being based on the oxides: 60% < ZrO2 + HfO2 < 75%; 27%.< SiO2 < 34%; O < TiO2; O < Y2O3 < 3.5%; 0.1 % < Nb2O5 + Ta205 <= 5%; and other oxides: < 1,5 %; for a total of 100%. Use in a glass furnace.