Sherardizing is a coating process that uses solid phase diffusion to apply a zinc-iron layer to a steel surface. This is why it is often referred to as zinc thermal diffusion. The resulting intermetallic zinc iron phases bond atomically to the base material , ensuring excellent protection from corrosion.
The diffusion bond between the zinc iron layer and the base material, in conjunction with passivation, provides active cathodic corrosion protection.
Sherardizing pursuant to DIN EN ISO 17668:2016 or DIN EN 13811:2003 takes place in a "zinc atmosphere" in a slowly rotating, closed chamber at temperatures of 350 °C to 500 °C. During a solid phase diffusion process the steel surface is coated with a zinc iron layer, whereby the zinc atoms penetrate the surface of the base material. Sherardizing allows uniform zinc iron layers between 10 μm and 100 μm to be applied closely following the contour of the base material.
When applied in a duplex system pursuant to DIN EN 15773:2010 with a cathodic dip coating, wet painting or powder coating, corrosion resistance is even greater, and e.g. the coefficient of friction as well as the color can be selected to meet the needs of the specific application.
Zinc diffusion is useful wherever extreme, active cathodic corrosion protection is required, e.g. in the construction and automotive industries, in traffic engineering, wind power or offshore technology.
FuseCoat is used anywhere that there is a need for outstanding cathodic corrosion protection and other functional and decorative properties combined in a duplex coating, e.g. in the automotive and construction industries, traffic engineering, wind power, the oil and gas industry or offshore.