Description

Magnesia brick Description

Magnesia brick is an alkaline refractory material. It is made of calcined magnesia or molten magnesia and can be divided into fired and unfired magnesium bricks. It is formed by high pressure and has good slag resistance. The firing temperature is 1500-1600°C.

Classification
It is divided into fired magnesia in brick and unfired magnesium bricks. Fired Magnesia brick is divided into silicate bonded Magnesia brick, direct bonded magnesium bricks and rebonded magnesia in brick. Unfired brick by magnesia is divided into chemical bonded magnesia in brick and asphalt bonded magnesia brick.

Other magnesia-containing refractory bricks

• Magnesia carbon brick
• Magnesia chrome brick
  
• Magnesia alumina spinel brick

Magnesia brick

Magnesia brick Technical parameter

From Wikipedia：Periclase、Refractory

magnesia in brick properties

• The refractoriness of bricks magnesia can reach above 2000℃C, the load softening temperature is between 1520~1600C, and high-purity magnesium bricks can reach 1800C.
• The thermal conductivity of magnesium bricks is high, and the thermal shock resistance is poor. Increasing the purity of magnesia bricks can appropriately improve the thermal shock resistance.
• The conductivity of Magnesia brick at room temperature is very low, but it cannot be ignored at high temperatures.
• The hydration resistance of magnesia in brick is poor. It is easy to hydrate when in contact with water, and cracks will occur, reducing its strength.

Magnesium bricks manufacturing process

The magnesia sand is crushed and mixed in a certain proportion, and an appropriate binder is added. It is formed under high pressure and sintered at high temperature.

Magnesia in bricks compared with other refractory materials

Compared with other types of refractory materials (such as silica bricks, high alumina bricks, carbon bricks, etc.), magnesia in brick have unique advantages in specific application areas (such as steelmaking converters, electric furnaces, basic open-hearth furnaces, etc.). However, due to its poor thermal shock resistance, magnesium bricks are not suitable for all high-temperature application scenarios. When selecting refractory materials, it is necessary to determine the most suitable material type based on the specific conditions and requirements of use.

How to improve the thermal shock resistance of magnesia in brick

1. Increasing the number of critical particles and coarse particles can make most of the thermal shock stability
2. Partially eliminating some stress can improve thermal shock resistance
3. If the thermal expansion coefficient of the product is large, the thermal stress caused by the temperature difference is also large, and its thermal shock stability is correspondingly poor
4. The stronger the thermal conductivity, that is, the greater the thermal conductivity, the smaller the internal and external difference, the smaller the temperature difference stress, and the stronger the thermal shock stability of the refractory brick
5. The better the elasticity of the refractory brick, that is, the smaller the elastic modulus, the stronger the ability to buffer the thermal stress, and the better the thermal shock stability of the product
6. The greater the structural strength, the stronger the ability to resist thermal stress, and the better the thermal shock stability of the product

What is the use of Magnesia Brick?

It is mainly used for basic steelmaking open furnaces, furnace bottoms and furnace walls, permanent linings of oxygen converters, smelting furnaces, high-temperature calcined magnesia bricks and linings, glass kilns, etc.

Market prospects of magnesia refractory brick

As a new type of thermal energy storage material, magnesium bricks have broad application prospects, especially in the field of renewable energy such as solar energy and geothermal energy.