Precautions for mid-range magnesia

Oxidation resistance: Carbon composite refractories have excellent thermal shock resistance and slag resistance due to the existence of carbon, but they have the defect of easy oxidation. Once carbon is oxidized, its advantages will be lost. Dead-burned magnesia, in order to give full play to the advantages of carbon composite refractories, often add appropriate additives to improve its oxidation resistance. Due to its active properties, metals are easy to react with O2 and CO, etc., and have been used as antioxidants in refractory materials. Al, Si, Mg and corresponding alloys are commonly used as antioxidants.

In-situ reaction to generate non-oxides: metals are introduced into refractory materials, and during the firing process, they are used to react with raw material components or surrounding gases to generate non-metal reinforced and toughened phases, which can improve the normal temperature and high temperature performance and resistance of the matrix. Thermal shock and other effects. At present, this technology has received extensive attention.

It can be seen from the above that the addition of metals to refractory materials has a positive effect on the mechanical properties and oxidation resistance of refractory materials, which indicates that they have broad application prospects in refractory materials. With the continuous development of science and technology and continuous breakthroughs in the field of science, the performance of metal composite refractories will continue to be optimized, and its application scope will be further expanded.

Dead burnt magnesia

      1. Molding: It is made of steel plate or hard wood board. The steel plate is coated with mold agent (oil), and the wood board is coated with waterproof paint. It should not leak slurry and have good strength.

2. Stirring: Stir with a mixer, first pour the castable into the mixer, and add the additives together, dry mixing for 2-3 minutes, then add water and mix for 3-5 minutes. The amount of water should not be too much or too little.

3. Vibration: The castable poured into the mold must be rammed immediately so that it does not leak to a certain position, nor can it be rammed at the same position to avoid segregation and holes in the castable. The stirred castable must be added from water to used up. Within 20-30 minutes, the initial set material should be discarded.

4. Curing: After the surface of the castable is dry and reaches 70% strength, the mold can be disassembled, the time is 24 hours, and the curing time is 48 hours.

5. Oven: According to the thickness of different grades and castable lining and its climatic conditions, the user must ensure a sufficient baking time of 72 hours.