Silicon nitride whisker reinforced magnesium aluminate spinel breathable refractory material and preparation method thereof

Abstract

The invention relates to a silicon nitride whisker reinforced magnesium aluminate spinel breathable refractory material and a preparation method thereof. The method comprises the following steps: taking 15-21 wt%, 30-39 wt% and 17-24 wt% of modified spherical porous magnesia-alumina spinel ceramic particles I, II and III as aggregates, and taking 2-4 wt% of magnesia fine powder, 3-6 wt% of corundum fine powder, 3-8 wt% of simple substance silicon powder and 8-20 wt% of spinel fine powder as substrates; firstly, placing the aggregates into a stirrer for stirring, adding a catalyst accounting for 0.1-0.5 wt% of the sum of the mass of the aggregates and the substrates, stirring, adding sulfurous acid paper pulp waste liquor accounting for 3-7 wt% of the sum of the mass of the aggregate and the matrix, and stirring;adding the substrates, stirring, forming, drying, preserving heat in theN2atmosphere at 1400-1600 DEG C, and cooling to obtain the silicon nitride whisker reinforced magnesia-alumina spinel breathable refractory material. The resource utilization rate is high, the microstructure is controllable, and the prepared product is uniform and stable in ventilation, high in strength, excellent in erosion resistance and excellent in thermal shock stability.

Description

technical field

[0001] The invention belongs to the technical field of magnesium aluminum spinel breathable refractory materials. In particular, it relates to a silicon nitride whisker-reinforced magnesium-aluminum spinel gas-permeable refractory material and a preparation method thereof. Background technique

[0002] Aluminum and its alloys are widely used in my country's manufacturing industry, and are the main structural materials in industries such as aerospace, automobile, rail transit and construction. However, with the rapid development of these industries, the requirements for aluminum and its alloy parts are increasing higher. Inclusions such as hydrogen and oxides are important factors affecting the quality of aluminum and its aluminum alloys. The bubble flotation method is to use breathable refractory materials to blow nitrogen into the melt of aluminum and its alloys to remove H in the melt. 2 Important methods such as gas and oxide inclusions, homogenization t...

Examples

Embodiment 1

[0081] A silicon nitride whisker-reinforced magnesium-aluminum spinel gas permeable refractory material and a preparation method thereof. The preparation method described in this embodiment is:

[0082] Step 1, preparation of spherical porous magnesium aluminum spinel ceramic particles

[0083] Step 1.1, with 33.3wt% magnesite fine powder, 64.7wt% aluminum hydroxide fine powder and 2wt% sawdust fine powder as raw materials, the raw materials are placed in a mixer and mixed for 2 hours; Add 4wt% binder of the raw material into the mixer, and stir for 30 minutes to obtain a mixture.

[0084] Step 1.2, prepare three kinds of spherical bodies respectively

[0085] Place the mixture in a granulator, add 2wt% water of the mixture, and spray under the condition that the rotation speed of the granulator is 4 rpm to obtain a spherical green body with a particle size of 4.5 ± 0.3mm I.

[0086]Put the mixture in a granulator, add 2wt% water of the mixture, and spray it under the cond...

Embodiment 2

[0108] A silicon nitride whisker-reinforced magnesium-aluminum spinel gas permeable refractory material and a preparation method thereof. The preparation method described in this embodiment is:

[0109] Step 1, preparation of spherical porous magnesium aluminum spinel ceramic particles

[0110] Step 1.1, using 35.4wt% magnesite fine powder, 61.3wt% aluminum hydroxide fine powder and 3.3wt% sawdust fine powder as raw materials, placing the raw materials in a mixer and mixing for 3 hours; Add 12wt% binder of the raw materials into the mixer, and stir for 34 minutes to obtain a mixture.

[0111] Step 1.2, prepare three kinds of spherical bodies respectively

[0112] Put the mixture in a granulator, add 5wt% water of the mixture, and spray under the condition that the rotation speed of the granulator is 4 revolutions / min, to obtain a spherical green body with a particle size of 4.5±0.3mm I.

[0113] Put the mixed material in a granulator, add 5wt% water of the mixed material, ...

Embodiment 3

[0135] A silicon nitride whisker-reinforced magnesium-aluminum spinel gas permeable refractory material and a preparation method thereof. The preparation method described in this embodiment is:

[0136] Step 1, preparation of spherical porous magnesium aluminum spinel ceramic particles

[0137] Step 1.1, with 37.1wt% magnesite fine powder, 58.9wt% aluminum hydroxide fine powder and 4wt% sawdust fine powder as raw materials, the raw materials are placed in a mixer and mixed for 4 hours; Add 9wt% binder of the raw material into the mixer, and stir for 38 minutes to obtain a mixture.

[0138] Step 1.2, prepare three kinds of spherical bodies respectively

[0139] Place the mixture in a granulator, add 7wt% water of the mixture, and spray it under the condition that the speed of the granulator is 4 revolutions per minute, to obtain a spherical green body with a particle size of 4.5 ± 0.3mm I.

[0140] Put the mixed material in a granulator, add 7wt% water of the mixed material...

technical field

[0001] The invention belongs to the technical field of magnesium aluminum spinel breathable refractory materials. In particular, it relates to a silicon nitride whisker-reinforced magnesium-aluminum spinel gas-permeable refractory material and a preparation method thereof. Background technique

[0002] Aluminum and its alloys are widely used in my country's manufacturing industry, and are the main structural materials in industries such as aerospace, automobile, rail transit and construction. However, with the rapid development of these industries, the requirements for aluminum and its alloy parts are increasing higher. Inclusions such as hydrogen and oxides are important factors affecting the quality of aluminum and its aluminum alloys. The bubble flotation method is to use breathable refractory materials to blow nitrogen into the melt of aluminum and its alloys to remove H in the melt. 2 Important methods such as gas and oxide inclusions, homogenization t...

Examples

Embodiment 1

[0081] A silicon nitride whisker-reinforced magnesium-aluminum spinel gas permeable refractory material and a preparation method thereof. The preparation method described in this embodiment is:

[0082] Step 1, preparation of spherical porous magnesium aluminum spinel ceramic particles

[0083] Step 1.1, with 33.3wt% magnesite fine powder, 64.7wt% aluminum hydroxide fine powder and 2wt% sawdust fine powder as raw materials, the raw materials are placed in a mixer and mixed for 2 hours; Add 4wt% binder of the raw material into the mixer, and stir for 30 minutes to obtain a mixture.

[0084] Step 1.2, prepare three kinds of spherical bodies respectively

[0085] Place the mixture in a granulator, add 2wt% water of the mixture, and spray under the condition that the rotation speed of the granulator is 4 rpm to obtain a spherical green body with a particle size of 4.5 ± 0.3mm I.

[0086]Put the mixture in a granulator, add 2wt% water of the mixture, and spray it under the cond...

Embodiment 2

[0108] A silicon nitride whisker-reinforced magnesium-aluminum spinel gas permeable refractory material and a preparation method thereof. The preparation method described in this embodiment is:

[0109] Step 1, preparation of spherical porous magnesium aluminum spinel ceramic particles

[0110] Step 1.1, using 35.4wt% magnesite fine powder, 61.3wt% aluminum hydroxide fine powder and 3.3wt% sawdust fine powder as raw materials, placing the raw materials in a mixer and mixing for 3 hours; Add 12wt% binder of the raw materials into the mixer, and stir for 34 minutes to obtain a mixture.

[0111] Step 1.2, prepare three kinds of spherical bodies respectively

[0112] Put the mixture in a granulator, add 5wt% water of the mixture, and spray under the condition that the rotation speed of the granulator is 4 revolutions / min, to obtain a spherical green body with a particle size of 4.5±0.3mm I.

[0113] Put the mixed material in a granulator, add 5wt% water of the mixed material, ...

Embodiment 3

[0135] A silicon nitride whisker-reinforced magnesium-aluminum spinel gas permeable refractory material and a preparation method thereof. The preparation method described in this embodiment is:

[0136] Step 1, preparation of spherical porous magnesium aluminum spinel ceramic particles

[0137] Step 1.1, with 37.1wt% magnesite fine powder, 58.9wt% aluminum hydroxide fine powder and 4wt% sawdust fine powder as raw materials, the raw materials are placed in a mixer and mixed for 4 hours; Add 9wt% binder of the raw material into the mixer, and stir for 38 minutes to obtain a mixture.

[0138] Step 1.2, prepare three kinds of spherical bodies respectively

[0139] Place the mixture in a granulator, add 7wt% water of the mixture, and spray it under the condition that the speed of the granulator is 4 revolutions per minute, to obtain a spherical green body with a particle size of 4.5 ± 0.3mm I.

[0140] Put the mixed material in a granulator, add 7wt% water of the mixed material...