A fused grain having the following chemical composition in percent by weight in relation to the oxides: ZrO.sub.2: 16% to 30%, provided that HfO.sub.2<2%, Al.sub.2O.sub.3: percentage needed to bring the total to 100%, Cr.sub.2O.sub.3: ≥0.2%, TiO.sub.2: ≥0.5%, Cr.sub.2O.sub.3+TiO.sub.2: <7%, other elements: <3%, provided that SiO.sub.2+CaO+MgO<1.5%.

A fused grain having the following chemical composition in percent by weight in relation to the oxides: ZrO.sub.2: 16% to 30%, provided that HfO.sub.2<2%, Al.sub.2O.sub.3: percentage needed to bring the total to 100%, Cr.sub.2O.sub.3: ≥0.2%, TiO.sub.2: ≥0.5%, Cr.sub.2O.sub.3+TiO.sub.2: <7%, other elements: <3%, provided that SiO.sub.2+CaO+MgO<1.5%.

Disclosed is a method for preparing an alumina-based solid solution ceramic powder by using an aluminum oxygen combustion synthesis water mist process, which comprises: drying raw materials and then mixing same until uniform to obtain a mixed material; loading the mixed material into a high-pressure reactor, igniting same in an oxygen-containing atmosphere, carrying out a high-temperature combustion synthesis reaction to form a high-temperature melt and then carrying out heat preservation for 1-60 s; and then opening a nozzle, ejecting the high-temperature melt through the nozzle and rapidly cooling same through a liquid phase, thus obtaining the alumina-based solid solution ceramic powder.

Disclosed is a method for preparing an alumina-based solid solution ceramic powder by using an aluminum oxygen combustion synthesis water mist process, which comprises: drying raw materials and then mixing same until uniform to obtain a mixed material; loading the mixed material into a high-pressure reactor, igniting same in an oxygen-containing atmosphere, carrying out a high-temperature combustion synthesis reaction to form a high-temperature melt and then carrying out heat preservation for 1-60 s; and then opening a nozzle, ejecting the high-temperature melt through the nozzle and rapidly cooling same through a liquid phase, thus obtaining the alumina-based solid solution ceramic powder.

The invention relates to a refractory plate for a sliding shutter for regulating a flow rate of liquid steel, to the use of a melt raw material as material in a plate of this kind and to a melt vessel for receiving liquid steel which has a plate of this kind for regulating a flow rate of liquid steel from the melt vessel.

The invention relates to a refractory plate for a sliding shutter for regulating a flow rate of liquid steel, to the use of a melt raw material as material in a plate of this kind and to a melt vessel for receiving liquid steel which has a plate of this kind for regulating a flow rate of liquid steel from the melt vessel.

Fused tuckstone defining lower and upper surfaces. The lower surface includes a support surface to rest on metallic structure of a glass furnace, a tank surface intended to face an upper edge of a tank of the furnace, and a lower transition surface connecting the support and tank surfaces. The upper surface includes a superstructure surface to receive a side wall of a superstructure of the furnace and an upper transition surface connecting the superstructure and lower surfaces. At least a part of the lower transition surface has a crystal density of more than four times the crystal density at a depth of 4 centimeters below the lower transition surface, a crystal density being evaluated by the number of crystals having a surface area of more than 12 m.sup.2 per mm.sup.2 of surface after polishing, the crystal density at the depth being evaluated after cutting of the tuckstone.

A method of fabricating a turbine engine part, the method including fabricating an ingot out of ceramic material of eutectic composition by performing the Czochralski process including putting a seed of the ingot that is to be obtained into contact with a molten bath of a mixture of eutectic composition in order to initiate the formation of the ingot on the seed, the mixture including at least two ceramic compounds; drawing the ingot from the molten bath while imposing on the ingot that is being formed a drawing speed less than or equal to 10 mm/h together with rotation at a speed of rotation less than or equal to 50 rpm; and machining the ingot as fabricated in this way in order to obtain the turbine engine part.

A method of fabricating a turbine engine part, the method including fabricating an ingot out of ceramic material of eutectic composition by performing the Czochralski process including putting a seed of the ingot that is to be obtained into contact with a molten bath of a mixture of eutectic composition in order to initiate the formation of the ingot on the seed, the mixture including at least two ceramic compounds; drawing the ingot from the molten bath while imposing on the ingot that is being formed a drawing speed less than or equal to 10 mm/h together with rotation at a speed of rotation less than or equal to 50 rpm; and machining the ingot as fabricated in this way in order to obtain the turbine engine part.

Provided are electrofused alumina grains capable of preventing grain binding on production and of achieving high grinding performance. The electrofused alumina grains of the present invention contain at least either one of tungsten or molybdenum.