Alu-zinc AZ185 is an aluminium-zinc coated steel sheet that can be used unpainted up to corrosive class C3. for AZ150 and C4 for AZ185. The name AZ150/AZ185 indicates the coat weight of 150/185 g/m2 per double side. The surface has been treated with SPT (Surface Protection Treatment) to prevent stains during handling and to ease shaping. The surface is initially glossy metal with a rose pattern but after some time it turns greyish, and eventually it becomes matt grey.
The long lifetime is due to the fact that the aluminium-zinc coating provides the steel sheet with a double protection against corrosion and therefor entails major environmental benefits. The warranty period is 20-years for AZ150 (C1-C3) and 30-years for AZ185 (C4).