1. Characteristics of light refractory materials
(2) Low bulk density
Bulk density refers to the ratio of the mass of the dried product to the total volume. The bulk density of lightweight refractories is very small, no more than 1.3g/cm³. At present, the bulk density of lightweight refractories commonly used in industry is 0.5~1.0g/cm³. The bulk density of the refractory material can reflect the apparent porosity of the product. It is a means to judge the degree of sintering of the product and marks the degree of compactness of the refractory material. In the production of lightweight refractories, in order to increase the apparent porosity and reduce the thermal conductivity, it is necessary to find ways to reduce the bulk density of the product.
(3) Low thermal conductivity
The physical meaning of thermal conductivity is: the amount of heat passing through a unit vertical area in a unit time under a unit temperature gradient. It is an important performance index for the quality of light refractory materials and an important index in thermal engineering design. It indirectly reflects the apparent porosity and bulk density of the product. For refractory products, the lower the thermal conductivity, the greater the apparent porosity. The thermal conductivity of lightweight refractories is very small, mostly less than 1.26W/m·℃.
Next issue we will continue to introduce characteristics of light refractories. Please stay tuned!