tcb greenkote

Greenkote is an advanced thermal diffusion coating of Zn-Al polymetallic composition. The patented process takes basic thermal diffusion to the next level of quality and durability.

The coating is a technically superior replacement for zinc plating, hot dip galvanizing, mechanical galvanizing and zinc flake dip-spin. Greenkote delivers exceptional protection against corrosion and provides superior adhesion, coating uniformity, is hard wearing and completely eliminates hydrogen embrittlement issues in high strength fasteners.

The Greenkote processes is completely eco-friendly and does not produce any toxics or pollutants, including heavy metals and Cr6+.

Greenkote coatings are applied by a patented Thermo-Chemical Surface Modification (TCSM) batch process which uses a dry bulk powder formulation of zinc, aluminium and other proprietary ingredients that is thermo-diffused into the iron-based metal substrate surface of finished metal parts. The Greenkote coating process forms a protective layer that is physically diffused into the substrate.

Metallurgically bonded, it cannot be easily separated by physical or environmental forces. In addition, the aluminium-rich inclusions dispersed on the surface serve to heal any micro fissures, cracks or porosity in the coating, while the zinc provides a sacrificial barrier against corrosion. The result is a highly uniform, conformal coating that gives exceptional protection against corrosion as well as enhanced durability and other performance advantages. The natural micro-roughness of the Greenkote surface gives it superior adhesion qualities for topcoats or paints.

Greenkote coating along with our unique passivation process provides corrosion protection durability level C5 high when tested in accordance with ISO 12944-6.


For more information about our Greenkote coating, please contact us.

Greenkote® anti-corrosion protection

Tension Control Bolts Ltd has its own metal coating plant producing an environmentally friendly anti-corrosion coating called Greenkote, which is comparable to galvanising, although it is harder wearing and readily accepts all paint systems. Learn more about Greenkote.