What Thermal Plasma Spray Is Used For

What Thermal Plasma Spray Is Used For

In order to deposit a material on a surface by spray coating which the base material itself does not possess, thermal plasma spray coatings are applied. The coating is applied by melting powder or a wire feedstock in a high-temperature plasma jet and spraying it onto a substrate where it immediately bonds.

Aerospace Turbine Components

Yttria-stabilised zirconia thermal barrier coatings (TBCs) are commonly applied using thermal plasma spray processes to components such as turbine blades and combustion chamber walls of nickel-base superalloy components. The function of the TBC is to insulate the metal from the high-temperature exhaust gases, thus preventing surface oxidation and associated creep.

Orthopaedic and Dental Implants

For orthopaedic/dental implants, such as hip/knee replacement stems, the powder used is hydroxyapatite, (Ca10(PO4)6(OH)2) a calcium phosphate ceramic that is very close to the bone mineral in natural bones. In a porous form, it enables bone ingrowth, which in many instances allows the component to be fixed without the use of cement.

Industrial Wear and Erosion Surfaces

Pump and fan components, such as impellers and blades as well as parts of conveyor components, are often coated with tungsten carbide or chromium carbide coatings. These hard ceramic coatings are especially effective where parts are subjected to abrasive particles or sliding wear.

Electrical Insulation Applications

Spray Coatings made from thermal Spray Coatings are used as dielectric coatings. They are used for heater mandrels, plasma containment components, as well as for other uses in the semiconductor processing industry. Plasma-sprayed alumina coatings have achieved strengths of up to 1.4 GVM (gigavol/meter).

Dimensional Restoration of Worn Parts

Plasma spray coating can also be used to dimensionally restore worn parts such as shafts, bores and wear surfaces of bearing seats, by first coating to oversize and then to re-mach to original dimensions to return to service at significantly less cost than new parts.

There are many surface properties that engineering materials cannot provide. Each of these applications are made possible by the core capability to deposit a material to meet a special surface requirement not provided by the base component.