What binder is used for high alumina bricks?

　　high alumina brick is a commonly used refractory material, usually made of high aluminate as the main raw material. When producing high alumina bricks, it is necessary to add an appropriate amount of binder to promote the solidification and hardening of the raw materials to form a strong high alumina brick product. The production of high alumina refractory bricks usually uses soft clay or semi-soft clay as a binder.

　　At present, in the production of high alumina bricks, the following binders are commonly used:

　　1. Soft clay binder

　　High alumina bricks usually use soft clay as a binder. However, the free SiO2 in the clay and the free Al2O3 in the high-alumina clinker undergo a secondary mulliteization reaction at 1200°C, resulting in greater volume expansion, increased silicon porosity, and reduced strength. Therefore, the amount of clay powder added to the ingredients should not exceed 5%.

　　2. Full alumina powder binder

　　Full alumina powder is a kind of high purity alumina powder with good chemical stability and high temperature stability. In the production process of high alumina bricks, adding an appropriate amount of full alumina powder can optimize the structure and improve performance.

　　3. Phosphate binder

　　Phosphate is a commonly used binding agent with high fire resistance and corrosion resistance. In the production process of high alumina bricks, adding an appropriate amount of phosphate can shorten the solidification time of the bricks and improve the mechanical strength and fire resistance of high alumina bricks.

　　4. Silicate binder

　　Silicate is a commonly used binding agent with high chemical stability and high temperature resistance. In the production process of high alumina bricks, adding an appropriate amount of silicate can promote the hardening and solidification of the bricks and improve the fire resistance of high alumina bricks.

　　It should be noted that the type and amount of binder will have a certain impact on the performance and service life of high alumina bricks. Therefore, the selection and proportioning of high alumina bricks should be based on actual conditions in the production of high alumina bricks.