What are the requirements for refractory materials in heat treatment furnace?
Fire resistance is an important performance index of refractory materials, but it does not represent the highest temperature in actual use of refractory materials. In actual use, refractories also bear certain pressure, therefore, must consider the high strength at high temperature refractory material, which is in high temperature under certain pressure without deformation, such as the NZ-40 refractory refractory degree up to 1730 DEG C, but the maximum temperature is only 1350 degrees celsius.
The structural strength of high temperature is evaluated by loading softening point. Load softening point is that under certain pressure (2 kg/ cm 2 = 0.2MPa) under the condition of heating rate to heating, measured the sample deformation (deformation for the original sample 0.6%) temperature. This temperature is called the softening point of the refractory. Sample size is Phi 36 x 50mm.
Refractoriness is the property of a refractory against high temperature, which means the temperature at which a refractory is softened to some extent after heating, but not its melting point. According to the degree of refractory, refractory materials can be divided into: General refractories, refractory degree is 1580 to 1770 DEG C; advanced refractories, refractory degree is 1770 to 2000 DEG C; special refractory material, refractory degree is greater than 2000 DEG C.
