Thermal barrier effect
Many high-temperature resistant coatings themselves have low thermal conductivity, such as ceramic high-temperature resistant coatings (such as zirconia coatings). When they are coated on the surface of the substrate, they can effectively block the transfer of heat, forming a "thermal barrier" in high temperature environments, reducing the conduction of external high temperatures to the substrate material, making the temperature of the substrate material relatively low, thereby avoiding performance degradation of the substrate due to prolonged high temperature conditions. For example, metal substrates can prevent rapid thermal expansion, softening, or even melting.
Antioxidant effect
In high-temperature aerobic environments, matrix materials (especially metal materials) are prone to oxidation reactions, leading to surface corrosion and performance degradation. High temperature resistant coatings can serve to isolate oxygen, such as coatings containing aluminum, silicon, and other elements, which form dense oxide films at high temperatures. For example, aluminum coatings form aluminum oxide films on their surfaces at high temperatures. These oxide films not only prevent oxygen from further contacting the substrate, but also have a certain degree of stability, which can maintain protection for the substrate for a long time, prevent the substrate from being oxidized and eroded, and extend its service life.
Reflective insulation effect
Some high-temperature resistant coatings can reflect thermal radiation, such as coatings prepared through special formulas and processes, which contain components that can efficiently reflect infrared and other thermal radiation. In high temperature environments, when heat radiation is transferred, the coating can reflect a large amount of heat radiation back, reducing the absorption of heat by the substrate and thereby lowering the temperature of the substrate, ensuring that the substrate works normally under high temperature conditions.
Chemical stability effect
High temperature resistant coatings often have good chemical stability. When facing various corrosive gases (such as sulfur dioxide, nitrogen oxides, etc.), molten salts, and other chemical substances that may exist in high-temperature environments, they can rely on their stable chemical structure to prevent chemical reactions, or the degree of reaction is minimal, thereby protecting the substrate from the corrosion of these chemicals, ensuring the integrity and performance of the substrate are not affected, and enabling the substrate to function normally in complex and harsh high-temperature chemical environments.
Enhance mechanical performance
There is a certain bonding force between the coating and the substrate. At high temperatures, it can reinforce the substrate and prevent mechanical properties such as cracking and deformation caused by thermal stress and other factors at high temperatures. For example, when the metal substrate expands due to heat, the coating can share some of the stress, relying on its own toughness, strength and other characteristics to maintain the stability of the overall structure, ensuring that the substrate can still maintain its original shape and function at high temperatures.

Room termperature curing polysilazane, pls check IOTA 9150, IOTA 9150K.    
High termperature curing polysilazane, pls check IOTA 9108, IOTA 9118.