The role of mid-range magnesia as a refractory material

The steelmaking production system for mid-range magnesia includes converters, electric furnaces, out-of-furnace refining furnaces, ladle and tundish equipment. In electric furnaces, dry vibrating materials, fused magnesia are prefabricated or cast-in-place furnace covers or furnace covers are used: Triangular areas and other parts have a better fire-resistant use effect; in converters and electric furnaces, fire-resistant spray coatings are generally used for appropriate repairs when damaged. The methods include manual patching, wet, dry, or flame spraying and slag splash protection. Furnace method, etc. In the converter, the traditional slag splashing furnace protection technology is commonly used, and the furnace age can reach nearly 10,000 times; there are many types of refining furnaces outside the furnace, and the RH method and DH method degassing devices are inserted into the corresponding pipe linings. The high-aluminum refractory castable is poured into a whole in a large area, and the service life is about 20 to 80 times. Ladle and tundish are important auxiliary industrial equipment for steelmaking furnaces, and are also thermal equipment that consumes the most refractory materials. Light burned magnesia

Mid-range magnesium for steel mills

The iron system includes sintering, coking, blast furnace and its auxiliary equipment. The ignition furnace of the belt sintering machine is made on-site with refractory plastic and clay combined with refractory castables, or hoisted with phosphoric acid refractory castable prefabricated blocks, and its service life is 3 to 6 years. When the linear ignition device is used, the furnace top pressure is more and the working conditions of the furnace become better. Lightweight high-strength refractory castables or refractory fibers and their products can be used as linings to obtain better results.

Promoting sintering: The sintering effect of metal on refractory materials can be attributed to two factors: First, the introduction of plastic phase forming formed by metal can increase the density of the green body, shorten the distance between particles, and reduce the diffusion and mass transfer during the firing process. The required energy; Second, the melting point of metal is generally lower than that of refractory raw materials, which can generate liquid phase at a lower temperature. The capillary force formed by the liquid phase and its own viscous flow accelerate the migration rate of atoms and the green body Shrinkage promotes the densification process of sintering.

Plastic phase forming: The metal lattice will slip under the action of stress, and it has plastic characteristics. It is introduced into refractory materials. Compared with the hard inorganic material particles, it will play the characteristics of plastic forming during the forming process, making the same The density of the green body prepared under the forming pressure is higher than that of the sample without metal.

Improve toughness: Metals can improve the toughness of composite materials through mechanisms such as crack bridging, crack deflection and crack barriers, among which crack bridging is the most effective toughening mechanism.