Architects, building designers and structural engineers love to incorporate the rich, organic look of weathering steels, such as COR-TEN® Steel, in their work. As demand for these steels grew, United States Steel Corp. (U. S. Steel), headquartered in Pittsburgh, PA, faced a challenge that was solved through a coil coating technique.

Architects, building designers and structural engineers love to incorporate the rich, organic look of weathering steels, such as COR-TEN® Steel, in their work. As demand for these steels grew, United States Steel Corp. (U. S. Steel), headquartered in Pittsburgh, PA, faced a challenge that was solved through a coil coating technique.

In some exterior architectural applications, COR-TEN steel does not provide enough structural integrity. U. S. Steel developed a new product called COR-TEN AZP® by coil coating its GALVALUME® steel sheet substrate. Utilizing coil coating's superior corrosion protection, U. S. Steel then worked to develop a paint finish that would mimic the color and texture of naturally aged weathering steel. The system the company chose includes a PVDF primer, brown topcoat and a contrasting overlay print. Additionally, the topcoat contains infrared reflective pigments in order

to make it a "cool roof" product, which meets energy codes and standards in many areas. These multiple paint layers require a two-pass process, as well as a special print-roll to apply the contrasting overlay. However, the process is made easy by working with a coil coater on a highly automated, continuous loop process prepaint system.

The resulting product mimics the look of COR-TEN steel and provides builders with the color and texture of weathering steel, while maintaining the structural integrity of the thin-gauge steel.

For more information about coil coating, visitwww.coilcoatinginstitute.org. U.S. Steel’s website is atwww.ussteel.com.