What is Thermal Spray?

What is Thermal Spray?

 Thermal Spray is a group of industrial coating processes.  Thermal spray uses a heat source (combustion or electrical;) to heat up a coating material in a (powder or wire form).  The heat source melts the power/ wire into tiny droplets (atomized) and sprays the material onto surface to form a coating.  See the diagram

There are several "Thermal Spray" processes:

Thermal sprayed coatings are typically sprayed onto metal substrates, but can also be applied to some plastic substrates. Thermal sprayed coatings uniquely enhance and improve the performance of the component

Typical Applications for Thermal Spray


  • Engine,
  • Landing Gear,
  • Actuator
  • Clearance Control/ Dimensional Restoration
  • Abradable
  • Thermal and Environmental Protections
  • Mechanical Wear Control

Power Generation Equipment:

  • Turbines, Compressors, Engines
  • Clearance Controll & Dimensional Restoration
  • Thermal and Environmental Protection
  • Mechanical Wear Control

Automobile Manufacturing:

  • Engine Block & Components
  • Cylinder bores,
  • synchromesh rings,
  • exhaust sensors,
  • fuel injection nozzles,
  • alternator caps,
  • piston rings,
  • stems and seats 
  • Mechanical, Thermal & Chemical Protection

Oil & Gas, Pulp & Paper, Steel, Mining, Chrome Replacement

  • Mechanical Wear 
  • Corrosion and Environmental Protection
  • Wear control, surface restoration, and salvage of paper calender rolls
  • Sealing, erosion and corrosion
  • Controls of pumps & valves

Definition of Thermal Spray:  Thermal Spray is defined as:

Group of processes where a material is heated (electric or combustion), atomized, and propelled unto a prepared substrate forming a functional coating.

Characteristics of Thermal Spray:

  1. Low temperature processing
  2. Low to elevated temperature service
  3. Thin to very thick
  4. Wide variety of coatings possible
  5. Good adhesion to substrate
  6. Coarse to smooth finish –
  7. post machining possible
  8. Components can often be re-coated –
  9. Provides additional service life
Thermal Spray in power industry

Thermal Sprayed Coatings

  • Resist Abrasion, Errosion, 
  • Retard Corrosion
  • Manage Thermal Efficiency
  • Thermal barriers
  • Enhance Electrical Properties
  • Control Dimensions & Clearances
  • Build up worn parts
  • Salvage worn Components
  • Manage Bond Coats

Reduce Cost Through Thermal Sprayed Coatings:

  • Better Performance
  • Longer Component Life
  • Decreased Maintenance
  • Lighter weight component

thermal spray chart temperature vs velocity