- Time:Jul 17, 2023
The thermal conductivity of low cement castables is usually between 0.5 W/(m K) and 1.5 W/(m K), depending on the formulation and material composition. The following is a detailed introduction to the factors affecting the thermal conductivity of low cement castables:
1. Cement content: Compared with traditional castables, low cement castables have lower cement content. Generally, cement has a higher thermal conductivity than other refractory particles, so low-cement castables help reduce overall thermal conductivity while reducing cement content.
2. Refractory particles: The main component of low-cement castables is refractory particles, such as alumina, mullite, silicate, etc. These refractory particles generally have a low thermal conductivity and play an important role in reducing the overall thermal conductivity.
3. Binders and fillers: A certain proportion of binders and fillers may be added to low-cement castables, such as Portland cement, silicate microspheres, etc. These materials generally have low thermal conductivity, which can further reduce the thermal conductivity of the castable.
4. Particle gradation and pore structure: The particle gradation and pore structure of low-cement castables will also affect its thermal conductivity. Reasonable particle gradation can reduce the connectivity of pores, thereby reducing the heat conduction path; at the same time, controlling the pore structure, such as increasing the closed pore rate or adopting a fine pore structure, also helps to reduce the thermal conductivity.
It should be noted that the above factors are only one of the common factors that affect the thermal conductivity, and the actual impact is also affected by other factors. In addition, the specific value of the thermal conductivity is also affected by the measurement method, temperature and other conditions.
When selecting low-cement castables, according to the needs of practical applications, it is necessary to comprehensively consider the thermal conductivity, fire resistance, mechanical strength and other indicators. In addition, manufacturers usually provide product technical data or laboratory test reports so that customers can choose suitable low-cement castables.
