High-strength zirconium-containing sintered fused mullite brick

Fused zirconia mullite bricks are special refractory materials made by using industrial alumina and zircon concentrate as raw materials, and introducing zirconia into the mullite matrix through a reaction sintering process. Introducing zirconia into mullite bricks, the use of zirconia phase transformation toughening can greatly improve the high temperature mechanical properties of mullite materials. Zirconium oxide can promote the sintering of mullite materials. The addition of ZrO2 can accelerate the process of densification and sintering of ZTM materials due to the generation of low melting points and the formation of vacancies.

 

Characteristics of Mullite Insulation Brick:

 

1. Low thermal conductivity, good thermal insulation effect;

2. Low thermal fusion, due to the low thermal conductivity, the mullite series light insulation bricks accumulate little heat energy, and the energy saving effect is obvious in intermittent operation;

3. Low impurity content has very low iron box alkali metal and other oxide content, so the refractoriness is high; the high aluminum content makes it maintain good performance under reducing atmosphere;

4. High compressive strength in hot state;

5. Appearance and size, speed up the masonry speed, reduce the amount of refractory mud, and ensure the strength and stability of the masonry, thereby extending the life of the lining;

6. It can be processed into special shapes to reduce the number of bricks and joints.

The refractoriness is high, which can reach above 1790 ℃. Load softening start temperature 1600 ～ 1700 ℃. Normal temperature compressive strength is 70 ～ 260MPa.

 

Good thermal shock resistance. There are two types of sintered mullite brick and fused mullite brick.

Sintered mullite bricks are made of high-alumina bauxite clinker, with a small amount of clay or raw bauxite as a binding agent, and are made by molding and firing.

 

The fused mullite bricks are made of high alumina, industrial alumina and refractory clay, with fine particles of charcoal or coke as the reducing agent, and are formed by reducing electric melting after molding.

 

The crystal of fused mullite is larger than that of sintered mullite, and its thermal shock resistance is better than that of sintered products. Their high temperature performance mainly depends on the content of alumina and the uniformity of the distribution of mullite phase and glass.