Why do magnesium oxide refractory bricks can be made into refractories?
The substance used in refractories must have the following characteristics and properties: 1, High stability: Anti-oxidation, anti-reduction and thermal decomposition; 2, High melting point of 2800 degree; 3, Low price. The magnesium oxide refractories have all these three characteristics and properties, particularlly in the aspects of melting point and stability .
Because the magnesium oxide, commonly known as magnesia, which is a basic oxide, with the common property of alkali oxides and belongs to the cementitious material . It is white or light yellow powder, odorless, tasteless, non-toxic and a typical of alkaline earth metal oxide, whose chemical formula is MgO. It is white powder, with melting point of 2852 ℃, boiling point of 3600 ℃ and relative density of 3.58 (25 ℃). The magnesium oxide that is soluble in acid and ammonium hydroxide solution has high insulation properity. After high temperature of above 1000 ℃ burning, it will transform into crystals, and when rising above 1500 ℃ , it will turn into dead-burned magnesium oxide (also known as the magnesia) or sintered magnesia. So the performance of magnesium oxide refractory bricks is good, and the fire resistance of it is very strong.
Nature: It is loose white powder and tasteless. When exposed to the air, it is easy to absorb moisture and carbon dioxide. It is dissolved in acid and ammonium salt and insoluble in water and ethanol, with the melting point of 2800 and the boiling point of 3600. The magnesium oxide has high fire-resistance insulation properties, with high melting point . It can be said to be non-combustible materials.
