Basic information
Thermal spraying is a promising technology that enables the creation of functionally effective coatings used across a range of industrial sectors. These flexible, high-quality and cost-effective technologies allow the surface properties of components to be optimally adapted to demanding operating conditions.
As part of a comprehensive solution, we are able not only to refurbish a component or apply a functional coating to it, but also to manufacture it as a new part based on technical drawings, a 3D model or a sample. We can therefore handle the entire order, from the manufacture of the base part through to the application of the coating, right through to final machining and dimensional inspection.
The application of thermal spray coatings addresses several key technical challenges:
- improving the technical performance of products,
- improving the operational reliability and service life of products,
- reducing production costs,
- reducing the energy consumption of production,
- refurbishing worn components.
Properties of the coatings produced
- resistance to mechanical wear, such as abrasion, erosion and cavitation,
- restoration of missing material to its original dimensions,
- resistance to combined stress,
- resistance to aggressive chemical environments,
- excellent tribological properties,
- resistance to corrosion and oxidation,
- resistance to extremely high temperatures,
- electrical insulation or electrical conductivity,
- biocompatibility,
- special physical properties.
Thermal Spraying Technology
Industrial sectors
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Mechanical Engineering
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Energy
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Mining & Metallurgy
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Petrochemicals & the Chemical Industry
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The paper, printing and textile industries
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The glass industry
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Pumping and Hydraulic Technology
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The electrical engineering industry
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The automotive industry
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The aviation industry
Coating materials
Coating materials represent an important group of engineering materials used to improve the surface properties of components. Their main purpose is to increase resistance to wear, corrosion, high temperatures or chemical stress, or to improve tribological, electrical or aesthetic properties. The choice of a suitable coating depends on the operating conditions and the requirements of the specific application.
Commonly used coating materials include carbides, which are characterised by very high hardness and resistance to abrasive wear. Carbide coatings consist of compounds of carbon with metallic elements and are primarily used where the surface is subjected to intense mechanical stress. Thanks to their hardness, they extend the service life of tools and machine components; however, their disadvantage may be lower toughness and greater brittleness.
Other commonly used materials include alloys, superalloys, ceramics and cermets.
Finishing of thermal sprays
A high-quality coating begins with a properly prepared surface and ends with precise finishing. We carry out grinding both before thermal spraying, when we prepare the part to ensure optimum coating adhesion, and after spraying as a final operation to achieve the required dimensions, shape and surface roughness.
Customers may have the coating machined at their own expense. However, we recommend that the final grinding be carried out by us. We have experience with specific types of thermal spray coatings, their hardness, structure and behaviour during machining. This enables us to select the correct technology, minimise the risk of coating damage and ensure a consistent result.
Hard spray coatings require the use of suitable diamond grinding wheels and correctly set grinding parameters. An unsuitable tool or procedure can lead to overheating, particle break-out, cracking or a reduction in the coating’s service life.
We handle the entire process, from preparing the base material through thermal spraying to the precise final grinding of the finished part.
FAQ | Frequently Asked Questions
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What are thermal sprays?
Thermal spraying is a surface treatment technology in which molten or partially molten material, in the form of powder or wire, is applied to a component. The resulting coating enhances the component’s resistance to wear, corrosion, high temperatures, abrasion and chemical stress.
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What materials can be applied using thermal spraying?
The materials used primarily include metal alloys, stainless steels, nickel alloys, bronzes, molybdenum, zinc, aluminium, ceramic materials, carbide coatings and combinations thereof. The correct material is selected according to the operating conditions of the specific component.
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For which components is this technology suitable?
Thermal spraying is used for both new and reconditioned parts, such as shafts, pins, hydraulic piston rods, bearing housings, cylinders, pump casings, moulds, rotating components, conveyor screws or parts exposed to abrasion and corrosion.
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Can a worn part be repaired using thermal spraying?
Yes. The technology is suitable for restoring the dimensions of worn surfaces, such as shafts, pins, bearing seats or piston rods. After application, the surface is usually machined, ground or polished to the required dimensions and surface roughness.
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What is the usual thickness of the coating?
The thickness of the coating depends on the technology used, the material and the purpose of the coating. It typically ranges from tenths of a millimetre to several millimetres. For precision surfaces, an allowance is made for subsequent machining.
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Is the coating firmly bonded to the substrate?
Yes, provided the surface is properly prepared and the appropriate technology is selected, the coating has very good adhesion. The bond is predominantly mechanical; in some systems, it may also be reinforced by a metallurgical bond or an adhesive interlayer.
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Does thermal spraying increase the dimensions of a component?
Yes. The coating adds material to the surface of the component. For functional or precision dimensions, therefore, grinding, turning, milling or honing is usually carried out after spraying.
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Is it possible to machine the sprayed surface afterwards?
Yes. Most coatings are finished by machining, most commonly by grinding. The chosen machining method depends on the hardness and type of coating. Carbide and ceramic coatings are generally ground using diamond or CBN tools.
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What is the service life of thermal spray coating?
Service life depends on the type of load, the environment, the coating material, the quality of surface preparation and the design of the component. In a suitably designed application, the coating can significantly extend the service life of the component and reduce the costs of repeated repairs or replacements.
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Is the coating also suitable for corrosion protection?
Yes. Zinc, aluminium, stainless steel or nickel coatings, for example, are commonly used for corrosion protection. The specific solution is chosen according to the environment, for example for outdoor structures, chemical plants, water management or marine applications.
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Can thermal sprays withstand high temperatures?
Yes, some materials are specifically designed for high-temperature applications. Examples include nickel alloys, ceramic coatings and special thermal barrier systems. It is always necessary to assess the operating temperature, thermal cycles and thermal expansion of the base material.
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What information is required for a quote?
To obtain an accurate quotation, please provide a drawing of the component, the material it is made of, photographs, a description of the operational load, the required thickness or final dimensions, the required surface finish and the estimated quantity. It would also be helpful to specify whether the part is new, a refurbishment or part of a repeat production run.
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Is it possible to supply the part including finishing machining?
Yes. An order can usually be handled as a complete service: initial assessment of the part, surface preparation, application of the coating, subsequent machining and grinding, and final dimensional inspection.
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How can I tell if thermal spraying is suitable for my component?
The best approach is to carry out a technical assessment of the specific application. The decisive factors are the material of the component, the type of wear, the operating temperature, the corrosive environment, the loads, the dimensional tolerances and the expected service life. Based on this information, a suitable coating and process can be proposed.