CLEVELAND, OHIO - August, 2007 - 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 Corporation (“U. S. Steel”) faced a challenge and a coil coating technique supplied the solution.

To answer the demand for COR-TEN® Steel - which sometimes is not the right material for certain exterior architectural applications - U. S. Steel developed a new product called COR-TEN AZP®. Created by coil-coating U.S. Steel’s GALVALUME® Steel Sheet substrate, the new 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.

Coil coating’s corrosion resistance and superior finish enabled U.S. Steel to bring this lightweight, durable product with a lasting color and texture finish to market. Because coil coating offers significant corrosion resistance, it was the ideal and obvious solution for U.S. Steel. Prepainting metal prior to fabrication and installation provides a far superior coating to post-paint application. It offers quality uniform coverage of the metal that eliminates edge-to-edge and side-to-side variability and drastically reduces the corrosion that unprotected metals are susceptible to over time.

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 they 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.

To learn more about coil coating, visit www.coilcoatinginstitute.org or call the National Coil Coating Association at 216-241-7333. The NCCA is an established trade organization dedicated to the growth of coil-coated products.

United States Steel Corporation, headquartered in Pittsburgh, Pa., manufactures a wide variety of steel sheet, tubular and tin products; coke, and taconite pellets; and has a worldwide annual raw steel capability of 26.8 million net tons. To learn more about U. S. Steel’s construction segment, visit www.ussteel.com and select Company, then Markets - Construction.