Kermetico HVAF and HVOF thermal spray equipment

Hastelloy Coatings – the HVAF and HVOF Corrosion and Wear Properties

The Kermetico HVAF ID Gun Thermal Spray Inside a Pipe

High velocity deposited Hastelloy* coatings provide high resistance to uniform corrosion attack, outstanding localized corrosion resistance and excellent stress corrosion cracking resistance.

Hastelloy C nickel-chromium-molybdenum alloys combine resistance to oxidizing and non-oxidizing environments.

Like many other nickel alloys, Hastelloy* coatings are ductile, easy to spray, and possesses exceptional resistance to stress corrosion cracking in chloride-bearing solutions (a form of degradation to which the austenitic stainless steels are prone).

With its high chromium and molybdenum contents, it can withstand both oxidizing and non-oxidizing acids and exhibits outstanding resistance to pitting and crevice corrosion attack in the presence of chlorides and other halides.

Furthermore, it is very resistant to sulfide stress cracking and stress corrosion cracking in sour oil field environments.

The Corrosion Resistance of HVAF Sprayed Hastelloy Coatings

The need for a metal coating appears when a corrosive attack is combined with elevated temperatures, abrasion or cavitation.

The resistance of thermally sprayed Hastelloy C-type coatings to aggressive factors is highly dependent on the coating’s porosity, bond strength and oxidation levels.

Kermetico HVAF coatings are characterized by significantly lower porosity and oxidation than HVOF coatings due to much lower process temperature, higher particle velocity and less oxygen in our HVAF process.

The Typical Properties of Kermetico HVAF Hastelloy Coatings

Pre-alloyed Hastelloy powder, gas-atomized.

Nominal composition wt.%
Nickelbase
Chromium16-17
Molybdenum16-17
Ironmax 2.0
Siliconmax 1.0
Manganesemax 1.0
Carbonmax 0.10

The Properties of the HVAF Hastelloy Coating

Apparent metallographic porosity<1.0%
Hardness, HRC28-30
Bond strength to carbon steel (@ 500 microns (0.020”) thickness), MPA (PSI)80 (12,000+)
Maximum coating thickness (as-sprayed), mm (inch)2 (0.080)
  • Machinable
  • Excellent resistance to corrosion in salt water, reducing acids, hydrogen sulfide and gases containing sulfur oxides
  • Good resistance to elevated temperature and dew-point corrosion

The Hastelloy coating is usually applied with our HVAF spray-blast technology and contains 5% aluminum oxide particles. It is very ductile and allows welding in proximity to the coating.

A Kermetico HVAF Corrosion Resistant Hastelloy Coating Micrograph, X100

A Micrograph of a Kermetico HVAF Hastelloy C Corrosion Resistant Coating, X100

Typical Applications of High Velocity Air Fuel Hasteloy Coatings

Used for corrosion protection of:

HVOF Thermal Spray Hastaloy Coating Inside a Vessel

HVAF Spraying Hastelloy Coating Inside a Vessel

Chevron has specified our HVAF Hastelloy coatings for vessels and reducers of oil refinery sulfur removal plants.

HVAF Equipment to Spray Hastelloy Coatings

Most of Kermetico guns can spray Hastaloy coatings.

  • Convertible HVOF and HVAF equipment:
    • C7 – an HVAF/HVOF gun for large parts, maximum spray rate – 22 kg (50 lbs.)/hour
    • C6 – a general purpose HVAF-HVOF gun, maximum spray rate – 16 kg (36 lbs.)/hour
  • Multi-purpose HVAF AK systems, with a variety of different spray guns:
    • AK7 – a high-power gun for the thermal spray of large parts, maximum spray rate – 22 kg (50 lbs.)/hour
    • AK5 – a compact gun to spray smaller parts, thin walls and complex surfaces, maximum spray rate – 8 kg (18 lbs.)/hour
    • AK-ID – an 80 mm (3.15”) and larger internal diameter spray gun, maximum spray rate – 3 kg (7lbs.)/hour
    • AK-IDR – a rotating ID gun to spray 4” (100 mm) and larger bores, maximum spray rate – 3 kg (7lbs.)/hour
    • AK-HH – a handheld gun for on-site coating, maximum spray rate – 8 kg (18 lbs.)/hour.
  • Additional equipment:

Kermetico, Inc. – Material Science Excellence, HVAF and HVOF Equipment Manufacturing and Thermal Spray Coating Services Since 2006

We create equipment that helps material scientists, engineers, and business managers achieve their goals.

We have installed more than 60 Kermetico HVAF systems in the USA, Europe, Japan, and China.

Some of the systems are at work in Universities and National Labs, but most of them are used in production thermal spray shops.

We proudly design and produce our HVAF thermal spray equipment in California and install it all over the world.

You can visit our R&D center in Benicia to meet our designers and see our HVAF equipment in action.

We also provide HVAF and HVOF thermal spray coating services for customers in the San Francisco Bay Area in California, USA.

*Hastelloy is a registered trademark of Haynes Inc.

Hastelloy Coatings – the HVAF and HVOF Corrosion and Wear Properties
5 (100%) 5 votes

Print page
Hastelloy Coatings – the HVAF and HVOF Corrosion and Wear Properties