Zircon powder plays a significant role in improving the thermal conductivity of refractories, mainly in the following aspects:

I. Improving thermal conductivity

Zircon powder has high thermal conductivity, which can effectively improve the thermal conductivity of refractories. Zirconium silicate (ZrSiO₄), its main component, has good thermal conductivity, which can quickly conduct heat in high temperature environment and reduce heat accumulation. For example, in high thermal conductivity oxide ceramic materials, adding a small amount of zircon powder can significantly improve the thermal conductivity of the materials.

II. Reducing the coefficient of thermal expansion

Zircon powder has a low coefficient of thermal expansion, which can maintain the stability of materials in high temperature environment. This characteristic is helpful to reduce the thermal stress of refractories when the temperature changes, thus improving their thermal shock resistance. For example, in some refractory formulations, the addition of zircon powder can effectively reduce the thermal expansion coefficient of materials and make them more stable in high temperature environment.

III. Compactness of reinforced materials

Zircon powder has fine particles, which can be evenly distributed in refractories to form a compact microstructure. This dense structure not only improves the mechanical strength of the material, but also enhances its thermal conductivity. For example, adding zircon powder to high-alumina brick can make anti-spalling high-alumina brick, and its thermal shock stability is significantly improved.

IV. Suppression of crack propagation

Zircon powder in refractories can enhance the damage tolerance of materials and inhibit the spread of cracks. Its main component, zirconia (ZrO₂), has high crack resistance, which can form stress resistance at high temperature and hinder the formation and propagation of cracks. This property not only improves the fracture toughness of the material, but also indirectly improves its thermal conductivity.

V. Improving the thermal stability of materials

Zircon powder's high melting point and good chemical stability enable it to maintain stable performance at high temperature. This stability is helpful to the long-term use of refractories in high temperature environment and reduces the decrease of thermal conductivity caused by the decrease of material properties.

VI. Summary

Zircon powder significantly improves the thermal conductivity of refractories by improving the thermal conductivity, reducing the thermal expansion coefficient, enhancing the compactness of materials, inhibiting crack diffusion and improving the thermal stability. These characteristics make it have a broad prospect in high temperature industrial applications.