Color coated with SSAB Zero steel sheets and coils

The scope of this EPD is GreenCoat® and color coated products with SSAB ZeroTM steels listed above. SSAB ZeroTM is made using 100 % recycled steel, of which over 90 % comes from external scrap (post- and pre-consumer) and the remainder from internal scrap from the manufac-turing process.

The steel is an alloy of mainly iron and carbon, with small amounts of alloying and trace elements. Alloying elements improve the chemical and physical properties of steel, such as strength, ductility, and durability. The exact composition of the steel manufactured by SSAB depends on product requirements, either from national and/or international standards, such as EN 10346, or on customer-specific standards. SSAB’s unique products also have their own specific requirements.

The base material in color coated products is typically metal coated steel. The metal coating, which is on both sides of the steel, is lead (Pb) free and has a zinc content of 92–100%. Its role is to prevent corrosion by keeping oxygen and water away from the steel and by acting as a cathodic protection. At cut edges or in case of damage through the metal coating, the coating will sacrifice itself and react to form a protective compound and block fur-ther corrosion processes.

SSAB’s color coated products typically have two paint layers, on both sides of the strip, and a pre-treatment.

These are applied typically to the metal coated steel in an automated process and cured at high temperature in a controlled process.

Pre-treatment improves the corrosion resistance and gives a good adhesion to the primer. The primer also pro-tects the product from corrosion and gives good adhesion to the topcoat. The topcoat is chosen based on the prod-uct’s end application. It gives the color and other chosen visual effects, but also largely defines the product’s overall performance. The total thickness of the color coating var-ies between 25 – 50 µm, depending on the product.

The sheet reverse side is typically painted with a two-layer gray reverse side coating which further enhances the product’s corrosion resistance. The reverse side coating is optimized to give good adhesion for adhesive bonded or foam filled sandwich panels. Where particular techni-cal or esthetic requirements are set for the reverse side, the coating can be selected accordingly. Typical overall reverse side coating thickness is 12 µm.