Amorphous refractory is a kind of refractory material which is mixed by refractory aggregate and powder, binder and admixture with certain particle size distribution, also known as loose refractory. For the lining of thermal equipment, without firing process, direct baking use. Compared with refractory brick, it has the characteristics of simple process (because of eliminating the firing process), saving energy, low cost and convenient mechanized construction.

The performance of refractory materials has three aspects:

(1) Mechanical properties. Such as compressive strength, flexural strength.

(2) Chemical properties. Such as slag resistance, reaction with controlled atmosphere.

(3) Physical properties. Such as bulk density, refractoriness, load softening temperature, thermal expansion rate, reburning line change rate, thermal shock stability, thermal conductivity and specific heat capacity. According to the use of refractory materials, starting from the comprehensive comparison of various properties required, several kinds of refractory materials are selected respectively, and finally confirmed according to investment and economic benefits.

The so-called workability of amorphous refractories refers to the comprehensive performance of measuring the difficulty of construction operation of amorphous refractories. Good operability means that perhaps shaped refractory materials can complete the construction operation process of mixing, conveying, watering, ramming, spraying and so on with less effort, and achieve stability and compactness when finally forming. Operability directly affects the construction efficiency and quality, and it is generally considered that operability includes the comprehensive performance of the four properties of mix fluidity, plasticity, stability and ease of densification.

1. Fluidity: Depending on the proportion of solid and liquid in the mix, usually increasing the water content will increase the fluidity.

2. Plasticity: refers to the ability to produce plastic deformation without "brittle break" under the action of a certain external force, which is related to the water-cement ratio and the content of cement slurry or binder.

3, stability: refers to the shear stress generated by the gravity of the aggregate in the mix does not exceed the yield stress of the "liquid phase", good stability of the mix, the aggregate particles are not easy to stratify according to size and the phenomenon of water secretion.

4, easy densification: refers to the ability of the mix to overcome internal and surface (and template) resistance during vibration or ramming to achieve complete densification.

The above four requirements for the operability of amorphous refractories will contradict each other in different occasions. For example, stability requires a high cohesion of the mix to reduce the sinking and bleeding of the coarse aggregate, while ease of densification requires a small cohesion and internal friction of the mix to make it easy to compact. Therefore, different requirements should be put forward for the operability of the mix according to the needs of different occasions.