Corrosion Resistant Coatings vs Thermal Spray
Why fluoropolymer corrosion barriers with chemical bond surface preparation outperform traditional sacrificial thermal spray on most chemical and marine service assets, and where thermal spray is still the right answer.
Two different ways to fight corrosion
Thermal spray and fluoropolymer barriers attack corrosion from opposite directions.
- Thermal spray deposits a sacrificial metallic anode (typically zinc or aluminum) that corrodes preferentially to protect the underlying steel. Excellent for atmospheric exposure on large structural steel. Limited in aggressive chemical service. Mechanical bond to a grit blasted substrate.
- AEGIS fluoropolymer corrosion barrier creates a chemically bonded, chemically inert film that the corrosive media cannot reach the substrate through. Excellent across a wide chemistry range including acids, caustics, chlorides, and ammonia. Field deployable cure.
Side by side
| Capability | Sacrificial thermal spray (Zn / Al) | AEGIS corrosion barrier |
|---|---|---|
| Bond mechanism | Mechanical, grit blast profile | Chemical, precision energy prep |
| Protection mechanism | Sacrificial anode | Chemical barrier |
| Atmospheric corrosion | Excellent | Excellent |
| Aggressive chemical service | Limited | Excellent |
| Complex geometries (threads, pockets) | Misses | Reaches every surface |
| Hazardous waste during prep | Yes, spent grit | None |
| Substrate damage during prep | Substrate degraded | Substrate preserved |
| Field deployable cure | Yes | Yes |
| Verified salt spray (ASTM B117) | 500 to 1,500 hours typical | 4,000 hour verified |
When sacrificial thermal spray is the right call
- Large structural steel in atmospheric marine or coastal exposure.
- Galvanic anode protection of submerged or buried steel where sacrificial behavior is the right protection mechanism.
- Service environments well matched to the thermal sprayed metal (pH near neutral, no aggressive chemistry).
- Bulk dimensional restoration plus general corrosion protection on shafts and journals.
When AEGIS corrosion barrier is the better answer
- Aggressive chemical service: acids, caustics, chlorides, ammonia, H2S, hypochlorite, hydrochloric, sulfuric.
- Bolts and threaded fasteners where every thread must be protected and grit blast cannot reach uniformly.
- Pumps, impellers, and reactor internals with mixed chemistry and abrasion.
- Onsite work where the heavy footprint of a thermal spray rig is impractical.
- Food, pharma, and hazardous area work where grit blast contamination is disqualifying.
- Any application where the bond line is the documented failure mode of prior coatings.
How to choose
Send AEGIS the asset details. We will spec the system and tell you when thermal spray is the better economic answer. We work with thermal spray applicators as well as compete against them, so the recommendation is based on what actually fits your service.
Frequently asked
Is AEGIS more expensive than thermal spray?
Per square foot, often comparable to slightly higher. Per documented service hour over the asset life, AEGIS is often cheaper because the bond line does not fail first. We quote both.
Can AEGIS coat over an existing thermal spray layer?
In some cases, yes. The existing thermal spray must be sound and contamination free. We assess and tell you whether strip and recoat or topcoat over existing is the right call.
How does AEGIS verify salt spray performance?
AEGIS coatings have been tested to ASTM B117 for 4,000 hours with no undercut from a scribe. The test panels and methodology are documented and available on request.
Can AEGIS handle high temperature corrosive service?
Yes up to 500°F continuous depending on the system, with excursions to 700°F for PFA grades. Above 750°F continuous, traditional ceramic or thermal spray may be the right answer.
What is the recoat interval on AEGIS corrosion barrier?
Service life depends on chemistry, temperature, and cycling. Documented field service life of 10 plus years is achievable in many chemical and marine applications. We quote expected service life with your spec.
Spec your corrosion protection
Send us the substrate, the chemistry, and the service environment. We will spec the right system, AEGIS or thermal spray, based on what actually fits.