High-temperature ceramic coatings are two-component polysilazane systems that cure — and in service, ceramify — into dense protective layers for 600 to 1000 °C duty. Where heat-resistant paints fade at 400 °C, these films convert toward inorganic Si-C-N structure and keep protecting: verified thermal-shock cycling, salt-spray endurance measured after 800 °C exposure, and a documented 1000 °C / 24 h result at the top of the line.
Four grades ladder the range. HT21 (black) and HT23 (white, 3:1 ratio) cover 600 °C continuous duty with 30-day corrosion protocols and five-cycle water-quench resilience. HT52 (gray/white) and HT53 (black-gray) are the ultra-high-temperature pair: 800 °C recommended service, 1000 °C / 24 h verification, and nitrogen-cure routes to 1300 °C.
| Grade | Product | Component Type | Pencil Hardness | Neutral Salt Spray Resistance | Thermal Shock Resistance | Curing (service <400 °C) | Service Temperature | Color | Component Type / Mixing Ratio | Appearance / Color | High-Temperature Resistance | Curing (air) | Recommended Service Temperature | High-Temperature Test |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| SILZ-HT21 | High-Temperature Anti-Corrosion Nano-Ceramic Coating | Two-component | ≥4H | 30 d: no blistering, cracking or rust | 600 °C (1 h) → water quench, >5 cycles: no visible cracking | 180 °C / 90 min (after 10 min tack-off) | Continuous up to 600 °C | — | — | — | — | — | — | — |
| SILZ-HT23 | High-Temperature Anti-Corrosion Nano-Ceramic Coating (White) | — | ≥4H | 30 d: no blistering, cracking or rust | 600 °C (1 h) → water quench, >5 cycles: no visible cracking | — | Continuous up to 600 °C | White | Two-component, A:B = 3:1 | — | — | — | — | — |
| SILZ-HT52 | Ultra-High-Temperature Anti-Corrosion Ceramic Coating | — | ≥8H | After 800 °C exposure, 30 d: no blistering or rust | — | — | — | — | — | Gray or white | 1000 °C / 24 h: no peeling or cracking | 260 °C or 500 °C / 1 h | -30 to 800 °C (air-cure max 700 °C; nitrogen-cure max 1300 °C) | — |
| SILZ-HT53 | High-Temperature Anti-Corrosion Ceramic Coating (Two-Component) | Two-component | ≥8H | ≥1000 h: no blistering, rust spots or peeling | — | — | — | — | — | — | — | 260 °C / 60 min | -30 to 800 °C | 1000 °C / 24 h: no peeling or cracking |
Comparison values from each product's TDS; “—” = full datasheet on request. Grades without a link are being migrated to the new site.
Duty to 600 °C → HT21/HT23 (oven schedules of 180–250 °C). Duty to 800 °C or exposure spikes beyond → HT52/HT53, with nitrogen-cure routes to 1300 °C when validated.
Black (HT21, HT53) hides service staining; white/gray (HT23, HT52) reflects heat and shows damage early for visual inspection programs. HT23 uniquely holds a white finish at 600 °C.
Thermal cycling → HT21/HT23 (>5 water-quench cycles at 600 °C). Post-fire corrosion → HT52 (30 d salt spray after 800 °C exposure). Extended endurance → HT53 (≥1000 h salt spray, 1000 °C / 24 h).
All four need heat: 180–260 °C oven schedules as standard, 500 °C air or nitrogen programs for top-tier duty. No oven? Use SILZ-RT31 from the room-temperature line (600 °C service, ambient cure).
High-Temperature Corrosion Protection
Specified films run just 10–40 µm. Protection comes from dense ceramic conversion and filler architecture, not bulk — which is exactly why over-thick films fail: they crack during conversion. Follow each grade's film window strictly.
Controlled first heating completes densification — the binder converts further toward inorganic ceramic. Each TDS ships with commissioning ramp guidance; follow it and the film's full endurance ratings apply.
Yes — send peak and continuous temperatures, substrate alloy, atmosphere (air, reducing, desulfurized flue gas) and cycling pattern. We return the grade, film build and cure schedule as a qualified system, with test panels on request.
Send us your substrate, application method and service conditions — our technical team replies within 1 business day.
