K-Tech

Bodycote K-Tech ceramics are a unique range of high quality thermochemically formed ceramic coatings for the prevention of corrosion and wear in a wide variety of industrial applications. They can be applied to most ferrous and some non-ferrous metals and are fundamentally different to all other techniques for depositing ceramics.

What distinguishes Bodycote K-Tech technology from almost all other deposition techniques for ceramics, carbides and metals is their unique corrosion barrier performance. All other techniques e.g. HVOF, plasma, airpsray, thermospray and electroplating result in coatings with inherent porosity. Micro-cracking can, and will, allow corrosion products to penetrate the coating, corrode the substrate at the interface and result in de-bonding and spalling of the coating. Even stainless steel substrates are not immune as the passive layer that provides the stainless properties can be interrupted during the coating process and not allowed to reform as it would in atmosphere.

The K-Tech range produces coatings that are chemically, not mechanically, bonded and have absolutely dense, pore-free corrosion barriers. They have a wide operating temperature capability – from cryogenic pump applications to gas turbine compressors. Due to the application process, geometries such as internal bores can be coated effectively. K-Tech coatings exhibit extreme hardness which significantly improves the life of mechanical components. They have a smooth, low friction surface and are anti-galling.

The K-Tech ceramic densification process significantly improves the corrosion resistance of other coatings. A composite ceramic material is thermochemically bonded to customer-specified areas on a part, including OD’s and ID’s and some out-of-sight holes and ports. Individual ceramic particles are sub-micron in size and consist of mixtures of selected ceramic materials bonded together and to the substrate. Porous after the initial formation of the ceramic, the K-Tech application is densified using ceramic precursor chemicals plus corrosion resisting chemicals. When thermochemically converted into ceramic and corrosion protection in situ, the densification processes form additional bonds and mass within the initial ceramic body. Each densification cycle fills some of the remaining porosity until a fully dense, non porous, corrosion-resistant ceramic coating has been created.

The K-Tech coating develops a bond into the substrate through the formation of a spinel-like interface between the ceramic coating and the metal surface. Part of the thermochemical reaction causes the substrate metal atoms to migrate into the ceramic coating during initial processing resulting in an extremely high bond strength to the substrate, in excess of 10,000 psi.

The unique combination of particle hardness, chemical bonding, and lack of porosity results in a coating which is unparalleled in wear resistance in corrosive environments. This has been proven in the field by the use of K-Tech coatings in downhole applications, resulting in life expectancies of components now being measured in years instead of days and weeks.