Five working magnesium carbon bricks for refractory materials

1. Plasticity of refractory materials, magnesium carbon brick manufacturers

Plasticity refers to the property that the refractory material and the binder and the diluent are prepared to a predetermined consistency and are not deformed when subjected to an external force, but the shape is changed but not cracked. In general, refractory materials incorporating a binder have a certain degree of plasticity. Refractory plastics, ramming materials, bonded clays or materials incorporating certain binders have more pronounced plastic properties, but mechanically pressed semi-dry molded articles have extremely poor plasticity.

2. Adhesion of refractory materials

Refractory brick masonry requires a material having a certain adhesive force at both normal temperature and high temperature, so refractory mud is usually used. Siliceous, clayy, high-aluminum, magnesia refractory mud, at room temperature, through the intermolecular forces, to achieve adhesion between refractory products. In a high temperature environment, ceramic bonding can be achieved due to sintering. In order to achieve ceramic bonding at a lower temperature, some sintering can be added to the slurry.

3. Resilience of refractory materials

The resilience of refractory materials is for spray coatings. During the spraying construction, the waste of the refractory spray coating and the unreasonable gradation of the sprayed layer particles are often caused by the rebound of the aggregate particles, and the bulk density is lowered, so that the service life of the inner liner is affected.

4, the consistency of the refractory material, the slurry

(1) Consistency is used to indicate the flowability of the refractory material. The concept of consistency is widely used in the construction of refractory muds, castables, plasticity and certain wet spray coatings. The specified metal cone is sunk into the flowable material. The sinking depth value is the consistency of the material, measured in 0.1 mm.

The adjustment of the consistency is mainly achieved by adjusting the particle gradation of the material and the ratio of the binder and the diluent. The consistency index can also be adjusted by adding an appropriate amount of water reducing agent.

(2) General slurry refers to the phenomenon that a layer of slurry is formed on the surface of the material due to vibration and beating during the construction of the refractory concrete. It is mainly caused by the continuous sinking of aggregate particles.

When a multi-layer refractory castable of a large volume or thickness is applied, the layer is vibrated, and the slurry layer is cut and the second layer is added. Because the surface of the pan-slurry layer is lighter, it is easy to cause thickness stratification

5. Hardening time of refractory materials

Hardening refers to the structure formed by the physicochemical change between the refractory and the binder, and the mechanical strength under certain external environmental conditions.

A variety of unshaped refractory materials, under the action of cement, do not need to be sintered at a high temperature, as long as the specific requirements are met, chemical or physical bonding can be achieved to achieve hardening of the refractory material and high strength. For example, various types of refractory cements, when mixed with refractory aggregates, powders and water, are cured and hardened over a period of time. High-temperature fired refractory materials, or hot-sprayed refractories, in the process of temperature drop, the original liquid phase vitrification or crystal activity is reduced to achieve the hardening process.