Here’s a list of some of the most well-known, leading global suppliers of round rolled aluminum bars:

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Leading Global Suppliers of Round Rolled Aluminium Bars

1. Alcoa Corporation

   • Headquarters: Pittsburgh, Pennsylvania, USA
   • Overview: A global leader in the aluminum industry, Alcoa produces a wide range of aluminum products, including rolled products.

2. Rio Tinto

   • Headquarters: London, United Kingdom
   • Overview: Known for its integrated aluminum operations, Rio Tinto offers various aluminum products, including rolled aluminum bars.

3. Novelis Inc.

   • Headquarters: Atlanta, Georgia, USA
   • Overview: A subsidiary of Hindalco Industries, Novelis is the world leader in aluminum rolled products and the largest recycler of aluminum.

4. Constellium N.V.

   • Headquarters: Amsterdam, Netherlands
   • Overview: Specializes in aluminum products and solutions, including rolled products for various industries.

5. Kaiser Aluminum Corporation

   • Headquarters: Foothill Ranch, California, USA
   • Overview: A leading manufacturer of semi-fabricated specialty aluminum products, including rolled aluminum bars.

6. Norsk Hydro ASA

   • Headquarters: Oslo, Norway
   • Overview: A global supplier of renewable energy and aluminum solutions, Hydro has an extensive portfolio of aluminum products, including rolled alloys.

7. Sapa Group (now part of Hydro)

   • Headquarters: Oslo, Norway
   • Overview: Before its acquisition by Norsk Hydro, Sapa was a leading aluminum manufacturer involved in rolling and extrusion.

8. Aleris Corporation (now part of Novelis)

   • Headquarters: Cleveland, Ohio, USA
   • Overview: Known for its rolled aluminum products, Aleris specializes in various end markets and applications.

9. Southern Aluminum Manufacturing Co., Inc.

   • Headquarters: Southern Pines, North Carolina, USA
   • Overview: A manufacturer that focuses on custom aluminum extrusions and rolled products.

10. Precision Castparts Corp. (PCC)

    • Headquarters: Portland, Oregon, USA
    • Overview: A major supplier of complex metal components and products, including aluminum alloys used in various applications.

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This list mentions some of the key players in the aluminum rolling industry. Many of these companies are involved in various segments of aluminum production and have a significant global presence.