Industrial Ceramic Coatings for Steel: Ceramic, Nano-Ceramic and Hybrid

Industrial Ceramic Coatings: Key Points

• An industrial ceramic coating is a film of hard ceramic material in a binder, bonded to blast-cleaned steel to resist heat, abrasion and corrosion; it is not a tile lining, a refractory or an automotive paint sealant.
• In Polylloy's portfolio three grades are ceramic: FlueGard®-455CHT (ceramic), KilnGard®-600SCW (nano-ceramic composite) and WearGard®-625S (nano-ceramic abrasion-resistant material).
• Polylloy uses "polymer-alloy-ceramic" as its family name for hybrid systems; FlueGard-225SQC (polymeric alloy) and FlueGard-425S (inorganic polymeric) are not ceramic coatings.
• Ceramic grades suit flue gas where heat, abrasion and condensate act together: FlueGard-455CHT lists good resistance to acidic and alkaline condensates to 455 °C (850 °F).
• None of the three ceramic grades is rated for immersion, and all are heat-cured; wet, acid-condensing baghouse service usually points to a different chemistry.
• Every grade needs a near-white abrasive blast with a profile above 3 mils (75 µm); certified partners apply under Polylloy supervision.

An industrial ceramic coating is a hard ceramic film, held in a binder and bonded to blast-cleaned steel, that resists heat, abrasion and corrosion in process equipment. Polylloy makes three: FlueGard-455CHT (ceramic, to 455 °C), KilnGard-600SCW (nano-ceramic, beneath refractory) and WearGard-625S (nano-ceramic, hot abrasion), each with its own listed service.

What an Industrial Ceramic Coating Is

An industrial ceramic coating is defined by what it is made of, how it attaches and what it is not.

Industrial Ceramic Coating Defined

An industrial ceramic coating is a protective film of hard ceramic material held in a binder and bonded to blast-cleaned steel, used to resist heat, abrasion and chemical attack in process equipment. It protects as a continuous bonded layer, unlike a ceramic tile lining or refractory, which protect by thickness.

The KilnGard-600SCW and WearGard-625S bulletins attribute their chemical and salt corrosion resistance to a "tough impervious ceramic nature and a strong bond to the metal substrate." Polylloy's brochure describes its hybrid systems as engineered for chemical resistance, thermal stability and abrasion protection.

What an Industrial Ceramic Coating is Not

An industrial ceramic coating is not the automotive "nano ceramic" paint protection sold for cars, which is outside this article. It is also not a ceramic tile or castable lining, which protects by sacrificial thickness, as the ceramic lining vs wear coating comparison explains.

Refractory insulates rather than seals the steel. A silicone heat paint is rated for dry exterior heat, not for process gas inside the equipment.

Ceramic, Nano-Ceramic and Hybrid Coating Chemistries

The three terms describe published chemistries, and they are not interchangeable.

How the Three Terms Differ

Each term maps to specific bulletins:

• Ceramic: the bulletin term for FlueGard-455CHT, a two-component, water-based ceramic corrosion and abrasion coating.
• Nano-ceramic: the bulletin term for KilnGard-600SCW, a nano-ceramic composite, and WearGard-625S, a nano-ceramic abrasion-resistant material.
• Hybrid: Polylloy Coatings' family name "polymer-alloy-ceramic" covers its hybrid systems, but not every grade in the family is a ceramic coating.

Chemistry Table: Which Polylloy Grades Are Ceramic

The table classifies five Polylloy grades by their published chemistry:

Selecting a grade by operating temperature is covered under coating grades by temperature and gas chemistry.

How a Ceramic Coating for Steel Resists Heat, Abrasion and Chemical Attack

A ceramic coating for steel is judged on hardness, abrasion loss and bond strength.

Hardness and Abrasion Data on the Three Ceramic Grades

Published Taber abrasion (CS-17 wheel, 1 kg, 1,000 cycles), hardness and adhesion data are:

Why the Bond to Steel Decides Performance

A ceramic film protects only while it stays attached. At a defect, condensate that reaches the steel can spread under a weakly bonded film. Polylloy laboratory and field testing comparing FlueGard with conventional high-temperature coatings observed undercutting corrosion and delamination in the conventional coatings.

KilnGard-600SCW and WearGard-625S report one-week immersion weight gain below 1.0% in 50% sodium hydroxide and below 0.5% in 36% sulfuric acid. These are laboratory property data, not an immersion service rating.

Where Industrial Ceramic Coatings Fit in Flue Gas and Kiln Service

Industrial ceramic coatings fit where heat, abrasion and corrosion act on the same steel.

Hot Flue Gas Ducts with Condensate and Dust

A ceramic coating is suitable for flue gas where the grade matches the duty. FlueGard-455CHT lists good resistance to acidic and alkaline condensates and high abrasion resistance to 455 °C (850 °F).

On about 75 m² of new duct at a Swiss cement plant, running 220 to 240 °C continuously with about 50 shutdowns a year, inspected areas showed no visible widespread delamination at about 17 months; heavy dust limited the inspection. The case is detailed in hot flue gas duct protection.

Kiln Shells and Furnaces Beneath Refractory

KilnGard-600SCW protects steel beneath refractory in cement and lime kilns. Its bulletin also lists waste-incineration furnaces and copper, zinc or lead smelter ducts, filters and stacks under refractory.

In Mexico, a kiln section lost more than 1.3 mm of shell in 11 months uncoated and showed no measurable loss over a further 12 months with KilnGard-600SCW; results are project-specific. The study is set out in kiln shell thickness loss, coated vs uncoated, and the product on the KilnGard nano-ceramic kiln shell coating page.

Hot Abrasive Ducts and Fans

The WearGard-625S bulletin lists high-temperature ducts in cement and lime, fans and ducts in coal power and waste incineration, and smelter ducts, filters and stacks. No completed WearGard-625S case study is published, so its proof is bulletin data.

Where a Ceramic Coating is Not the Usual Choice

Wet, acid-condensing baghouse service within 225 °C usually points to FlueGard-225SQC, a polymeric alloy rated for immersion, rather than a ceramic grade. The FlueGard family is described on the FlueGard high temperature coatings page.

Industrial Ceramic Coating Compared with Ceramic Linings, Thermal Spray and 316 Stainless

Three alternatives come up whenever an industrial ceramic coating is proposed.

Three Alternatives in One Paragraph Each

A ceramic tile or castable lining is a thick sacrificial layer for impact and extreme wear. It adds weight, and its joints can admit gas to the steel.

Thermal spray deposits metallic or cermet layers by line-of-sight application, and its porosity needs sealing where condensate forms. Options of that kind are compared among the high temperature coatings above 400 °C.

316 stainless steel is Polylloy's primary benchmark, and it can pit under chloride-bearing condensate. Protected carbon steel may offer a cost-effective alternative to stainless steel where the coating is suitable for the specified service conditions.

Application Requirements for an Industrial Ceramic Coating

Application requirements are the same discipline for all three ceramic grades.

Preparation, Film Build and Cure

The sequence runs in four steps:

1. Blast to SSPC-SP10 (Society for Protective Coatings) / NACE No. 2 near-white metal with a profile above 3 mils (75 µm), for every grade.
2. Mix and thin the water-based coating with distilled water only.
3. Apply the film build: FlueGard-455CHT in two coats to 16 to 20 mils total; KilnGard-600SCW as a single coat of 15 to 25 mils, before the refractory goes in.
4. Cure in service: final heat cured activation is completed during start-up using process heat.

Certified partners apply the coatings, while Polylloy formulates, supplies, specifies, trains and supervises. Outage sequencing is covered in the coating outage planning steps.

Limits of Industrial Ceramic Coatings

An industrial ceramic coating has clear limits that should be checked before specifying.

What a Ceramic Coating Cannot Do

Five limits apply:

• Thin wear allowance: heavy lump impact still calls for liner plate or tile.
• It does not replace refractory; KilnGard-600SCW protects the shell behind it.
• These are not immersion grades: KilnGard-600SCW and WearGard-625S are not rated, and the FlueGard-455CHT data sheet states no immersion rating.
• It needs a near-white blast and start-up heat; a site that cannot provide both is not a fit.
• Mild service: where steel is dry, cool and chemical-free, a conventional coating is adequate.

Deciding Whether an Industrial Ceramic Coating Fits Your Equipment

Deciding whether an industrial ceramic coating fits comes down to duty.

Decision Rules

Use these rules as a first screen:

• Heat plus abrasion plus acidic or alkaline condensate up to 455 °C: evaluate FlueGard-455CHT.
• Steel behind refractory: KilnGard-600SCW.
• Hot abrasive gas streams to 625 °C: WearGard-625S.
• Liquid contact, or acid-condensing service within 225 °C: look beyond the ceramic grades.

Pricing depends on the operating environment, selected coating system, equipment condition, project size, and application requirements. The wider portfolio is set out under corrosion protection solutions. To test the fit on your equipment, request a coating evaluation and book a Coating Performance Review with equipment type, coated area, operating conditions (temperature, gas chemistry, abrasion), location and outage timing.

FAQs

What is an Industrial Ceramic Coating?

An industrial ceramic coating is a hard ceramic film, held in a binder and bonded to blast-cleaned steel, that resists heat, abrasion and chemical attack in process equipment. It protects as a continuous bonded layer, unlike a ceramic tile lining or refractory. Polylloy's ceramic grades are FlueGard-455CHT, KilnGard-600SCW and WearGard-625S.

What is the Difference Between Ceramic and Nano-Ceramic Coatings?

Both use a hard ceramic phase bonded to steel; the label follows the manufacturer's description of the material. Polylloy's FlueGard-455CHT is published as a ceramic coating, while KilnGard-600SCW and WearGard-625S are published as nano-ceramic materials. Compare grades on their data sheets, service limit, abrasion data and listed equipment, not on the label alone.

Is a Ceramic Coating Suitable for Flue Gas?

A ceramic coating can suit flue gas where the grade matches the duty. FlueGard-455CHT is a ceramic coating with good resistance to acidic and alkaline condensates and high abrasion resistance to 455 °C (850 °F). For wet, acid-condensing service within 225 °C, such as many baghouses, an immersion-rated polymeric alloy like FlueGard-225SQC is usually evaluated instead.

Can a Ceramic Coating Be Applied to Carbon Steel?

Yes, Polylloy's ceramic grades are applied to carbon steel after abrasive blasting to SSPC-SP10 near-white metal with a profile above 3 mils (75 µm). FlueGard-455CHT lists more than 1,000 psi (7 MPa) Elcometer adhesion on sandblasted carbon steel. Certified partners apply the coatings under Polylloy specification and supervision.

Is FlueGard-225SQC a Ceramic Coating?

No. FlueGard-225SQC is a two-component polymeric alloy, and FlueGard-425S is a single-component inorganic polymeric coating. Polylloy uses polymer-alloy-ceramic as a family name for its hybrid systems, but only FlueGard-455CHT, KilnGard-600SCW and WearGard-625S are published as ceramic or nano-ceramic materials, so specify by grade code rather than family name.

How Thick is an Industrial Ceramic Coating?

Polylloy's ceramic grades are thin films measured in mils. FlueGard-455CHT goes on in two coats to 16 to 20 mils (400 to 500 µm) in total, and KilnGard-600SCW as a single coat of 15 to 25 mils (0.38 to 0.63 mm). That thin bonded film adds little weight but leaves a limited wear allowance where heavy lumps strike.

Do Industrial Ceramic Coatings Need Heat to Cure?

Polylloy's three ceramic grades are heat-cured, and final heat cured activation is completed during start-up using process heat, so the plant's start-up after the outage completes the cure. Where start-up heat cannot reach a coated area, Polylloy's technical team defines the approach for that project. CorrosionGard-160S is the ambient-cure grade, and it is not a ceramic coating.