Sintered particle in the form of ball, useful for treating surface of bottles, comprises composition of e.g. zirconium oxide and hafnium oxide, silicon oxide and aluminum oxide, and crystallized phases of e.g. zircon, mullite and corundum

摘要

Sintered particle comprises a composition of 30-55 wt.% of zirconium oxide and hafnium oxide, where an amount of the hafnium oxide is = 2 wt.%, 18-35 wt.% of silicon oxide, 6-40 wt.% of aluminum oxide, 0.5-6 wt.% of magnesium oxide, = 5 wt.% of boron oxide and 9 wt.% of other oxides, and crystallized phases of 32-80 wt.% of zircon, 3-15 wt.% of mullite, = 9 wt.% of optionally stabilized zirconia and hafnium, 4-37 wt.% of corundum and 10 wt.% of other crystallized phases, where the sintered particle has a porosity of = 6%. Independent claims are included for: (1) a powder comprising more than 90 wt.% of sintered particles; (2) a process for producing sintered particles comprises grinding raw material powders by co-grinding method to provide particulate mixture having a median size of less than 0.6 mu m, optionally drying the particulate mixture, preparing a feedstock from the dried particulate mixture to prepare sintered particles having the composition, where the feedstock comprises glass particles containing magnesia, glass ceramic particles containing magnesia and/or a compound containing magnesium oxide and silicon oxide, formatting the feedstock in the form of raw particles and then optionally washing and drying, and sintering the particles at a temperature of 1330-1410[deg] C; and (3) a device such as a suspension, a grinder, a surface treatment apparatus and a heat exchanger, comprising the powder comprising sintered particles.