Types of Fabrication of Coil Anodized Aluminum

Roll forming is a continuous bending operation in which sheet or strip metal is plastically deformed along a linear axis. Tandem sets of rolls (known as roll stations) shape the metal in a series of progressive stages until the desired cross-sectional configuration is obtained. As a continuous process, roll forming is ideal for producing parts with long lengths or in large quantities. Coil anodized aluminum can be easily roll-formed like many other metals into many different configurations of width, height, and pattern. One example of an application is the Mercedes-Benz Superdome in New Orleans, Louisiana (see case study one).

Honeycomb panel construction typically consists of an aluminum honeycomb core sandwiched and bonded between two anodized aluminum sheets. This provides high rigidity and an extremely low weight. It is particularly applicable as wall cladding for high wind load locations and large self-supporting structures.

Composite panel construction. These panels are typically comprised of a polyethylene or thermoplastic core sandwiched between two anodized aluminum sheets.

Solid panels can be formed using a press brake machine that bends metal. The lower part of the press contains a V-shaped groove. The upper part of the press contains a punch that will press the sheet metal down into the V-shaped die, forcing it to bend.

Examples of how anodized aluminum can be fabricated into formable panels Image courtesy of Lorin Industries

Stamped. Anodized aluminum can be formed into many components just like other metals such as steel, copper, brass, and zinc. A metal sheet is stamped or pressed on a machine using dies and hydraulics to create the designs. It is performed in rapid succession and involves various techniques for the types of shapes and designs that are being created. Pre-anodized aluminum may not be able to sustain a deep drawn stamped part.

Other fabrication processes include laser engraving, silk screening, chemical and mechanical etching, and high-pressure laminating.

Case Study Coil Anodized Aluminum Honeycomb Panels, Gyeongju Tower, South Korea

Photo courtesy of Lorin Industries The Gyeongju Tower, part of the Gyeongju World Cultural Expo Park located in Gyeongju City, North Gyeongsang Province, South Korea, is an architectural landmark achievement. The 17-story (82-meter) building was built with a cut-out in the center resembling the legendary nine-story, sixth century Hwangnyongsa Temple’s wooden pagoda in South Korea. The principal architect, building owners, and city officials were interested in a reflective, metallic finish that would illuminate the structure and show off their ancestral heritage. They were also insistent that the honeycomb fabricated panel have a durable finish, be corrosion resistant, and have a consistent panel-to-panel match. Anodized aluminum honeycomb panels with a clear matte finish maintained, rather than covered, the aluminum’s reflective properties unlike so many buildings in Korea that are obviously painted. Since the anodized aluminum was processed in a continuous coil operation, the panel match quality far exceeded expectations as compared to batch anodizing producers. Since the aluminum oxide layer is three times harder than the aluminum itself, durability of the finish was not a concern.