Magnelis® is the first zinc-magnesium-aluminium steel coating to be certified for use in marine environments. The distinctive metallic composition of Magnelis® creates a stable, robust and self-healing layer across the entire surface of the metal. For operators of solar installations, Magnelis® offers more than 25 years of almost maintenance-free support.
SP Sitac, an international approval and certification body for the construction sector, has tested Magnelis® and qualified the coating for use in C5-M (marine) environments. This enables Magnelis® to be utilised in coastal areas with high salinity.
The main reason CWF uses magnelis® is the quality and durability of the coating.
The 3% magnesium in Magnelis® is crucial as it provides a far more effective defence against corrosion than coatings with a lower magnesium content. With less zinc than conventional galvanisation, the coating also protects valuable resources for future generations and reduces the environmental impact from zinc runoff to soil. Magnelis® also performs up to ten times better than galvanised steel.
By selecting a Magnelis® coating for the structural elements, operators can extend the life of their solar farms and maximise return on investment.
“The main reason we use Magnelis® is the quality and durability of the coating,” explains Jürgen Wolpert, owner of CWF, a leading producer of mounting systems for open-field photovoltaic installations. “Another reason is the logistical advantage Magnelis® offers. We can fabricate the parts and skip the costly and timeconsuming process of batch galvanisation. This saves us a week of processing and enables us to meet the short lead times this sector demands.”
Magnelis® ZM310 (25 μm) is the most used coating in solar applications and offers a guarantee of up to 25 years. ArcelorMittal recently developed Magnelis® ZM430 which has a thicker (35 μm) coating. ZM430 offers the best possible protection in more aggressive soils and in areas subject to higher abrasion.
Thanks to ArcelorMittal International, Magnelis® can be utilised in solar projects wherever they are located in the world.
Compared to other zinc-coated steels available on the market, Magnelis® coated steel has shown remarkably consistent adhesion performance in a series of tests conducted by Sika Services, a leading supplier of adhesives to the solar industry.
All tested adhesives showed adhesion build-up on the virgin substrates, independent of the coating type. However, adhesion performance after severe ageing conditions, especially after 1,000 hours of neutral salt spray (EN ISO 9227), showed major differences.
Adhesion to the electrolytically galvanised steel was affected by heavy corrosion creep. “This means the degradation of the zinc coating progressed even underneath the complete bond line,” explains Michael Niederfuehr, an engineer for Sika Services who is responsible for solar applications. “This led to complete loss of adhesion after the 1,000-hour salt spray test.”
Standard batch-galvanised steel grades showed the first signs of corrosion creep along the edge of the adhesive joint. This slightly reduced the strength of the bonded assembly.
“By comparison, the Magnelis® substrates were unaffected by any of the applied ageing conditions with regard to long-term adhesion performance,” notes Michael Niederfuehr. “We only saw typical optical impairments as evidence of the ageing procedures carried out.”
