Abstract: The invention relates to a sintered ball that has the following crystallized phases, in mass percentages based on crystallized phases and for a total of 100%: stabilized zirconia: remainder up to 100%; monoclinic zirconia: ?20%; 4%?magnetic component?22%; crystallized phases other than stabilized zirconia, monoclinic zirconia and magnetic component: <10%; the magnetic component being chosen from among magnetic spinels, magnetic garnets, magnetic hexagonal ferrites and mixtures thereof; the sintered ball comprising, in addition to the magnetic component, CeO2 and optionally Y2O3, in contents that, in molar percentages on the basis of the sum of ZrO2, CeO2 and Y2O3, 3%?CeO2?17.5% and 1.5%?Y2O3+(CeO2)/3.5?5%.

Abstract: A sintered bead with the following crystal phases, in percentages by mass based on crystal phases: 25%?zircon, or “Z1”, ?94%; 4%?stabilized zirconia+stabilized hafnia, or “Z2”, ?61%; monoclinic zirconia+monoclinic hafnia, or “Z3”?50%; corundum?57%; crystal phases other than Z1, Z2, Z3 and corundum<10%; the following chemical composition, in percentages by mass based on oxides: 33%?ZrO2+HfO2, or “Z4”?83.4%; HfO2?2%; 10.6%?SiO2?34.7%; Al2O3?50%; 0%?Y2O3, or “Z5”; 0%?CeO2, or “Z6”; 0.3%?CeO2+Y2O3?19%, provided that (1) CeO2+3.76*Y2O3?0.128*Z, and (2) CeO2+1.3*Y2O3?0.318*Z, with Z=Z4+Z5+Z6?(0.67*Z1*(Z4+Z5+Z6)/(0.67*Z1+Z2+Z3)); MgO?5%; CaO?2%; oxides other than ZrO2, HfO2, SiO2, Al2O3, MgO, CaO, CeO2 and Y2O3<5.0%.

Abstract: Sintered bead that has a crystalline composition, as percentages by weight based on the total weight of the crystalline phases: zircon<25%; 50%?cubic zirconia+tetragonal zirconia?95%, the cubic zirconia content being greater than 50%, the cubic zirconia content being the (cubic zirconia/(cubic zirconia+tetragonal zirconia) ratio by weight); 0?monoclinic zirconia?(10?0.2*tetragonal zirconia) %; 5%?corundum?50%; crystalline phases other than zircon, cubic zirconia, tetragonal zirconia, monoclinic zirconia and corundum<10%; and the following chemical composition, as percentages by weight based on the oxides: 34%?ZrO2+HfO2, ZrO2+HfO2 being the remainder to 100%; HfO2?4.0%; 0.5%?SiO2?14.1%; 4.5%?Al2O3?49.6%; 2.75%?Y2O3?22.8%; MgO?5%; CaO?2%; oxides other than ZrO2, HfO2, SiO2, Al2O3, MgO, CaO and Y2O3<5.0%.

Abstract: A sintered ball having: a chemical composition such that, in percentages by mass based on the mass of the ball: 89%?W?97%; 5%?C?8%; Co?0.5%; Ni?0.5%; Elements other than W, C, Co, and Ni, or “Other elements”: ?3%; a tungsten carbide(s) content greater than 55% in percentage by mass based on the crystallized phases; a bulk density greater than or equal to 14 g/cm3.

Abstract: A sintered bead with the following crystal phases, in percentages by mass based on crystal phases: 25%?zircon, or “Z1”, ?94%; 4%?stabilized zirconia+stabilized hafnia, or “Z2”, ?61%; monoclinic zirconia+monoclinic hafnia, or “Z3”?50%; corundum?57%; crystal phases other than Z1, Z2, Z3 and corundum<10%; the following chemical composition, in percentages by mass based on oxides: 33%?ZrO2+HfO2, or “Z4”?83.4%; HfO2?2%; 10.6%?SiO2?34.7%; Al2O3?50%; 0%?Y2O3, or “Z5”; 0%?CeO2, or “Z6”; 0.3%?CeO2+Y2O3?19%, provided that (1) CeO2+3.76*Y2O3?0.128*Z, and (2) CeO2+1.3*Y2O3?0.318*Z, with Z=Z4+Z5+Z6?(0.67*Z1*(Z4+Z5+Z6)/(0.67*Z1+Z2+Z3)); MgO?5%; CaO?2%; oxides other than ZrO2, HfO2, SiO2, Al2O3, MgO, CaO, CeO2 and Y2O3<5.0%.

Abstract: A bead having a sphericity greater than or equal 0.6 and made of a fused product having the following chemical composition, in percentages by weight on the basis of the oxides and for a total of 100%: 20%?(ZrO2+HfO2), with HfO2?2%, 5%?SiO2, 0%?Al2O3?20%, 8.5%?MgO?20%, 0.5%?TiO2?20%, and oxides other than ZrO2, HfO2, SiO2, Al2O3, MgO and TiO2, or “other oxides”: ?5% provided that the (ZrO2+HfO2)/SiO2 weight ratio is greater than 1, and provided that Al2O3+TiO2?26% if MgO>17%.

Abstract: A sintered bead presenting the following chemical analysis, in percentages by weight and for a total of 100%: ZrO2+HfO2: 78%-85%; CeO2: ?15%; Al2O3: >0.1%; additive: >0.1%; impurities: <1%; the additive being selected from MnO, MnO2, Fe2O3, CuO, TiO2, Y2O3, Sb2O3, ZnO, and mixtures thereof. Application to microgrinding and to microdispersion.

Abstract: The invention relates to a molten ceramic particle, characterized in that it has the following chemical composition in wt % based on oxides and for a total of 100%: 55%<ZrO2+HfO2<70%; 20%<SiO2<30%; 6.5%<MgO<9.5%; Al2O3 in an amount such that the mass ratio MgO/Al2O3 is comprised between 2.4 and 6.6; and less than 0.6% of other oxides.

Abstract: The present invention provides a fused ceramic particle, having the following chemical composition, in percentages by weight based on the oxides and for a total of 100%: 50%<ZrO2+HfO2<70%; 10%<SiO2<30%; 6.5%<MgO<9.5%; Al2O3 in a quantity such that the MgO/Al2O3 weight ratio is in the range 2.4 to 6.6; 0.1%<Y2O3; CeO2<10%; and less than 0.6% of other oxides. Use in particular as milling agents, wet medium dispersion agents, propping agents, heat exchange agents, or for the treatment of surfaces.

Abstract: The present invention provides a fused ceramic particle, having the following chemical composition, in percentages by weight based on the oxides and for a total of 100%: 50% <ZrO2+HfO2<70%; 10% <SiO2<30%; 6.5% <MgO<9.5%; Al2O3 in a quantity such that the MgO/Al2O3 weight ratio is in the range 2.4 to 6.6; 0.1% <Y2O3; CeO2<10%; and less than 0.6% of other oxides. Use in particular as milling agents, wet medium dispersion agents, propping agents, heat exchange agents, or for the treatment of surfaces.

Abstract: A molten product in the form of a particle having a sphericity higher than or equal to 0.6, having the following chemical composition, in weight percent based on the oxides and for a total of 100%: (ZrO2+HfO2): complement to 100%, 6%?CeO2?31%, 0.8%?Y2O3?8.5%, 0%?Al2O3?30%, 0%?SiO2?17%, 0?TiO2?8.5%, 0?MgO?6%, and other oxides?1%, provided that, by denoting by “C” the weight ratio CeO2/(ZrO2+HfO2) and by “Y” the weight ratio Y2O3/(ZrO2+HfO2), 0?C?0.6 and Y?0.02 and Min(63.095*Y2?11.214*Y+0.4962; 0.25)?C ??(I) and C?250*Y2?49.1*Y+2.6 ??(II).

Abstract: The invention relates to a molten ceramic particle, characterized in that it has the following chemical composition in wt % based on oxides and for a total of 100%: 55%<ZrO2+HfO2<70%; 20%<SiO2<30%; 6.5%<MgO<9.5%; Al2O3 in an amount such that the mass ratio MgO/Al2O3 is comprised between 2.4 and 6.6; and less than 0.6% of other oxides.

Abstract: A sintered bead presenting the following chemical analysis, in percentages by weight and for a total of 100%: ZrO2+HfO2: 78%-85%; CeO2: ?15%; Al2O3: >0.1%; additive: >0.1%; impurities: <1%; the additive being selected from MnO, MnO2, Fe2O3, CuO, TiO2, Y2O3, Sb2O3, ZnO, and mixtures thereof. Application to microgrinding and to microdispersion.