▶ RECHERCHE ET DÉVELOPPEMENT DE MATÉRIAUX ET PROCÉDÉS…
...from the laboratory to the industrial production
La Recherche et le Développement de matériaux et de nouveaux revêtements avec des études de faisabilité et essais est une activité principale de TCPP. La Recherche et le Développement se fait d’une part sur les matériaux et d’autre part sur les procédé. Les matériaux travaillés sont les céramiques (oxydes, carbures, nitrures, …), les métaux et alliages, les polymères ou des composites de ces matériaux. Les procédés utilisés ou développés sont ceux projection thermique (projection plasma, HVOF, flamme, arc-fil et au canon à détonation) ou Cold Spray et ceux de mise en forme de dépôts sous vide par PVD.
TCPP offre à ses clients toutes les facettes des procédés de projection thermique, de projection Cold Spay et de procédés PVD, allant des études de faisabilité avec essais de validation aux contrats de productions. Ceci passe par le développement de nouveaux revêtements et de nouvelles applications dont quelques unes d’entre elles sont présentées dans la suite.
Recherche et Développement de matériaux : Revêtements dans les alésages
The system includes a rotating bore rod. One application is the lining of crankcases of automobile engines. This application is patented.
The advantages of the process are:
> Ease of integration online
> Speed of realization of the coating
> Large selection of materials
The driver developed by TCPP
Recherche et Développement de matériaux : Decoration and architecture
The process developed and patented by TCPP consists in the thermal spraying process using a metallic coating on concrete supports, traditional ceramic (terracotta) or wood. Various colors and metallic aspects such as copper, bronzes, brass, aluminum, zinc can be made on the surface of the substrates to be treated and give them a new undeniable aesthetic appearance. This metal film applied on the surface of precast concrete elements also offers the advantage of protecting its support against various types of attack such as pollution and acid rain. Possible architectural applications range from the construction of civil engineering works (prefabricated concrete panels) and housing structures (buildings) to that of urban or domestic furniture.
Copper and zinc coatings on oak panel
Copper cladding made by TCPP on the facades of a building
Coatings and liquid metals
In the case of metal foundries of light alloys (aluminum, zamac, ...), the coatings developed by TCPP can increase the life of the parts (cast ladles, pyrometric canes, ...) while allowing in some cases to avoid potage.
Ladles and different foundry tools coated with TCM82 coating
To avoid the seizing phenomena of pipe elements (used for example in the petroleum industry), TCPP has developed a TCM12 copper base coating. Its thermal projection is fast and clean from an environmental point of view. The coating is applied to the threads of the pipe fittings to be screwed. The coating is gas tight.
Pipe end threads used in the oil industry protected with copper base coating TCM12
Recherche et Développement de matériaux : Plastic coatings
Thermally sprayed coatings are used on plastic substrates for certain industrial applications. Most of these coatings are based on zinc or aluminum, they are mainly made for electro-magnetic screen or electrical conductivity applications and when the mechanical properties sought are not of primary importance. For certain mechanical parts manufacturing applications, thanks to a high mechanical strength / weight ratio, the use of fiber-reinforced plastics is an interesting alternative to metals. The weak points of fiber reinforced plastics are their poor surface properties. Applications that require coatings with good mechanical properties, for example to withstand wear, are few because of the difficulty of obtaining sufficient adhesion between the plastic substrate and the coating. Recent work has shown the feasibility by thermal spraying of high performance coatings on fiber reinforced polymers. A precise choice of material combinations implemented and the use of specific projection parameters made it possible to produce thick coatings of metals, ceramic oxides and carbides which can ultimately be machined or ground.
Pipes made of carbon fiber reinforced polymer coated with WC-8Co, NiCrBSi, Al2O3 and Al2O3-3TiO2
Micro-structure of a carbon fiber reinforced polymer coated with alumina
APPLICATION: thermal barriers on plastic
The goal is to increase the performance and reliability of plastic components by protecting them from the effects of heat and providing them with new strength properties.
The advantages of thermal barriers applied to plastic substrates are illustrated by the following photos which show the degradation and flame resistance of a burner (during 35 seconds of exposure) of coated and uncoated plastic substrates
Degradation of coated and uncoated plastic components subjected to a burner flame for 35 seconds
left: coated - right: uncoated
Plasma forming of complex parts
For their use in the field of high temperatures, ceramic pieces with complex shapes, such as tubes, crucibles, ... require good properties of resistance to thermal shocks, which can be difficult and expensive to obtain with conventional methods. TCPP has solved this manufacturing problem by shaping high-purity powders by a process of thermal spraying (plasma forming) to obtain parts of complex geometries with unique properties and advantages such as:
> high resistance to thermal shock
> low cracking ability
> a reliable manufacturing process to produce in quantity
> parts free of residual stresses
Ceramic parts obtained by plasma forming
Colored ceramic coatings
Alumina coatings are mainly used for their dielectric properties or for abrasion resistance applications. The coatings are white. For some applications, in addition to these properties, it may be interesting to have color for aesthetic effects. By addition of rare earths or pigments to alumina powders it is then possible to obtain colored coatings. Blue, green, pink, orange and yellow colors are now available. These alumina coatings offer the advantages of better resistance to abrasion and erosion than conventional paint, all of which brings color. It is also possible to engrave writings or patterns on these alumina coatings.
Various colored alumina coatings
For conveyor belt rollers or other industrial components requiring a rough surface, TCPP has developed a range of roughness-controlled coatings; the average roughness can be adjusted between 10 μm and more than one millimeter. These coatings also offer excellent wear resistance.
Rough coating on a training roll