Thermal Spray Coatings

Air Plasma Spray (APS) Coatings

Air Plasma Spray (APS) is a high-energy, high-temperature coating technique that uses a controlled plasma arc to heat and propel ceramic or metallic powders onto a surface. While widely recognized for producing thermal barrier coatings (TBCs) on turbine blades, vanes, and combustors—providing critical resistance to extreme heat and oxidation—APS technology is applied across a much broader range of uses.

APS enables the deposition of coatings such as:

• Abradable seal coatings for clearance control in compressors and turbines, improving efficiency.
• Wear and erosion resistant coatings using materials like chromium carbide or tungsten carbide to extend component life in severe environments.
• Oxidation and corrosion resistant overlays, including alumina and MCrAlY systems, to protect hot-section parts from degradation.
• Electrical and dielectric coatings, such as alumina, for insulating surfaces in aerospace and industrial equipment.
• Functional ceramic layers tailored for chemical resistance, biocompatibility, or other specialized applications.

This versatility makes APS a cornerstone technology in aerospace, power generation, and industrial markets—delivering dense, strongly bonded coatings that enhance performance, reliability, and service life of critical components.”

Flame Spray

Flame spray is a thermal spray technique that uses a high-temperature combustion flame to melt and propel metal or ceramic powders onto a surface. Although it doesn’t produce coatings with the same density or bond strength as more advanced methods, it remains a cost-effective solution for applications needing moderate wear resistance, thermal insulation, or dimensional restoration.

In gas turbine engines, flame spray is often applied for abradable coatings in clearance control systems, helping to reduce airflow leakage and improve overall efficiency in compressors and turbines. In industrial settings, it is widely used as an economical repair method for restoring worn components such as pump sleeves, shafts, and various machinery parts.

Wire Arc

Wire arc spray is a thermal spray process that melts metal wire using an electric arc, then atomizes the molten material with compressed air or inert gas to form a coating. Known for its high deposition rate, this method is ideal for restoring dimensions on worn components in gas turbines, industrial engines, and rotating equipment—such as bearing journals, shafts, and seal surfaces.

In turbine systems, wire arc spray is also used to apply abradable coatings for clearance control, particularly in compressor casings and shroud sections, where they help preserve optimal operating efficiency. These coatings offer strong wear resistance and enhance performance in components exposed to friction and high mechanical stress. Widely used in maintenance, repair, and overhaul (MRO) operations, wire arc spray plays a key role in extending the service life of expensive turbine parts and industrial machinery.