Corrosion resistance, Surface sealing, Abrasive surface
The SealPlex® ranges of coatings are used to surface seal and fill the porosity in other materials. Surface treatments such as nitro-carburising and tuftriding create a porous outer layer. This layer has excellent liquid retention properties and when subjected to the SealPlex® densification process, a singlephase ceramic layer is chemically bonded into and over the porous outer layer. The SealPlex® coating produced in this way is <5µm thick with a hardness up to 2,900 VPN. In addition to the significant increase in surface hardness, corrosion resistance and frictional properties are improved. The same techniques can be used to seal the surface of other porous materials such as solid ceramics and sintered metals. If the impregnation is vacuum assisted, full penetration of the porous structure can be achieved and filled to produce a harder and stronger component.
Flame sprayed coatings and electroplated hard chrome can also benefit from the SealPlex® densification process. These coatings are by nature micro-cracked and porous and therefore susceptible to interface corrosion problems. The penetration performance of the SealPlex® is so efficient that the microcracks in hard chrome can be filled to improve both wear and corrosion performance.
SealPlex® has a unique effect on other coatings and treatments. It can be used to seal hard chrome plate, plasma, HVOF (High Velocity Oxy-Fuel) and Thermal Spray coatings. The resultant duplex coating exhibits increased ductility and increased fracture toughness brought on by a change in failure mechanism from inter granular (around grain boundaries) cracking to trans granular (through grains) cracking. The activation energy associated with this change in failure mechanism and consequently the coatings toughness is greatly increased.