High-temperature coating
A protective coating formulated to stay adherent and intact on a substrate held above the service limit of a conventional system. Evaluated for high-temperature service by the methods of ASTM D2485. It protects the surface and does not meaningfully reduce the substrate's temperature.
The term is regularly read as though the coating did something thermal. It does not. A high-temperature coating protects the steel it sits on from its environment while that steel runs hot; it is not insulation, and it is not a refractory lining, which is dimensioned as a thermal and chemical barrier at working thickness.
What it shares with every other coating is that the substrate condition it goes over decides its life. ASTM D2485 covers how such coatings are evaluated for service; it does not relax the preparation grade named on the product’s own data sheet, which remains the specification.
Sources and references
- StandardASTM D2485-18, Standard Test Methods for Evaluating Coatings For High Temperature ServiceASTM International · accessed September 7, 2026