Thermal spray coating (TSC) is a local melting (softening) of the material and its spraying by high speed compressed air or gas jet. After contact with a solid substrate droplets flatten, mix and create a coating (surface).
Coating materials available for thermal spraying include wire, powder or powder-filled polymer.
The coating precursor is heated by:
- welding arc (plasma spraying);
- electric arc is generated between two consumable metal wires (wire arc spraying);
- mixture of oxygen and fuel gases (detonation spraying);
Thermal spraying can provide coatings of any composition over inner and outer surfaces of various parts. Coating materials available for thermal spraying include metals, alloys, ceramics, plastics and composites (thickness range is 20-30 micrometers). The thickness is limited by the economic feasibility of coating.
Significant advantages are: equipment usability, low cost, versatility, the possibility to organize the process of spraying in any conditions, as well as the possibility of obtaining different properties of coatings on various substrates.
The benefits of TS coating:
- reduction of cost and repair time;
- application of cheaper materials or fewer due to the wear resistant, corrosion-resistant, heat-resistant, heat-conducting, conductive and insulating coatings;
- creation of structures that require special coatings: rocket and aircraft engines, components of nuclear reactors and MHD generators, aircraft landing gear made of titanium alloys, etc.;
- products weight reduction by applying light coatings instead of sleeves, facings, shirts, reduction of the temperature gradient, etc. (space objects, chemical and power equipment).
This technique is mostly used in nuclear engineering, high temperature physics, metallurgy, mining, chemical and agricultural engineering, medical engineering, construction, transport engineering, electrical engineering and other industries that require coating heat-, erosion- and wear-resistant, corrosion resistant, electrically conductive and insulation, with high or low coefficient of friction, for the restoration of worn surfaces, sealing of cracks and other purposes.
The company uses this technology for spraying bronze, antifriction, ceramic, thermal erosion and anticorrosion coatings.
Application at YUZHMASH
Application of technology in the manufacture of parts of landing gear for AN aircraft:
- anti-friction wear-resistant bronze coating on pistons, rods, axle-boxes, which reduces the number of parts, weight and simplifies structure;
- coatings of tungsten, cobalt, nickel, aluminum, using titanium alloys in landing gear design;
- zinc corrosion resistant coating that provides corrosion resistance of steel parts during life time.
Thus, TSC make it possible to manufacture parts for AN landing gear, and any costs to develop and apply this technology are economically effective.
Since 1963 YUZHMASH is equipped with facilities for plasma spraying: UPU-3D, UPU-8M, and electric plating BM-2 complex. Spraying is carried out on specialized machines that allow applying coating on the outer and inner surfaces of parts of variable cross section.
The quality of coatings performed at Yuzhmash meets all the requirements for products that are made for international programs and projects – “Cyclone” launch vehicle, “Vega” liquid rocket engine, landing gears for AN aircraft.
More than 40 years experience in coatings together with high qualification of engineers and technicians of YUZHMASH allows solving complex technical tasks.