Main performance indicators of refractory

 
1. Fire resistance: Fire resistance is the resistance of refractory materials to melting at high temperatures. Refractory mainly depends on the chemical composition of refractory and the content of fusible impurities (such as FeO, NaO, etc.) in the material. Fire resistance is generally determined by tests. A material with a refractory greater than 1580 ° C can be called a refractory.
2. High-temperature structural strength: High-temperature structural strength refers to the resistance of refractory products under pressure without deformation. Often evaluated by the softening temperature of the load.
3. Thermal stability: Thermal stability refers to the ability to resist rapid changes in temperature without cracking or flaking, and is sometimes referred to as resistance to rapid cooling and rapid heating.
4. Volume stability: Volume stability refers to the percentage change in the volume of the refractory products repeatedly heated and cooled at a certain temperature.
5. High temperature chemical stability: High temperature chemical stability refers to the ability of refractory products to resist metal oxides, molten salts and furnace gas erosion at high temperatures. Slag resistance is commonly used for evaluation. This property mainly depends on the chemical characteristics and physical structure of the phase composition of the refractory product itself, such as porosity and bulk density.
6. Bulk density, porosity, and air permeability: Bulk density refers to the weight of a unit of refractory products including all pores, and its unit is g / cm3.
7. Thermal conductivity, specific heat capacity, thermal expansion: Thermal conductivity indicates the thermal conductivity of refractory materials, and is often expressed by the symbol "λ". Its physical meaning is the heat of refractory products with a thickness of 1m and an area of ​​1m2 per unit time when the temperature difference is 1K.