Contrarian Micro Textures, a high-performance architectural metals company serving clients throughout the world, has just added another InvariMatte® stainless steel finish to its roster of products: InvariMatte® Black, a non-directional, uniformly textured finish with a thin black oxide film. The lineup of InvariMatte® stainless steel finishes has proved popular in many market sectors and, in particular, has allowed Contrarian Micro Textures to gain a strong foothold in the airport construction market.
InvariMatte® Black is designed for use in many architectural applications, and can be applied to roofing and wall panels, as well as coping and trim. The black chromium oxide film is produced electrochemically in collaboration with Prismatic Stainless Steel, a division of B & M Finishers, Inc.
“Unlike blackened zinc or painted metals, InvariMatte® Black offers a rich dark finish that will last indefinitely, since the oxide film does not react to ultraviolet light or atmospheric conditions”, said Jim Halliday, of Contrarian Micro Textures.
Metal, particularly stainless steel, is showing up more frequently on newly-constructed airport exteriors across the country. The trend marks an important juncture for airport construction specifiers mindful that some metal products are less suitable for airport settings than others – those that have reflective properties, require paint, or corrode when exposed to jet fuel emissions. Not so with Contrarian Micro Textures’ InvariMatte®, a corrosion-resistant, uncoated stainless steel finish with low glare and a long lifecycle.
In addition to sun, wind, and precipitation, airport exteriors are continually exposed to jet fuel residue, earth-rumbling engines and the repercussions of heavy traffic. The materials used to construct these exteriors must stand up to these elements and maintain an aesthetic standard. Stainless steel accomplishes both goals.
InvariMatte® resists the threat of corrosion from atmospheric conditions and trapped moisture.
Data collected from the Nickel Development Institute indicates that aluminum, a common alternative to stainless steel, corrodes several times faster. While a layer of paint is effective for extending the life of an aluminum panel, it can actually have a detrimental effect on corrosion resistance if that layer is breached and moisture is trapped at the metal interface. Incidental damage to roof panels – punctures in the paint, or dents and dings – can easily occur from routine maintenance or weather events, such as hailstorms. If moisture and contaminants – like sulfur dioxide and chlorides – are trapped at the metal surface, rapid deterioration, known as crevice corrosion, will occur.
With InvariMatte®, no paint is needed, allowing the natural beauty of stainless steel to shine through.
“Prismatic helped us respond to customers who wanted a sustainable black finish,” said Halliday. “More common stainless steel finishes are rather bright and remain so after electrochemical colorizing. The dull InvariMatte® finish remains dull when colorized, creating a desirable surface appearance. The combination of our InvariMatte® finish with Prismatic’s workmanship create a unique product solution that is being well-received by designers.”
Aside from physical damage done to them, painted surfaces do not stand up well in an airport environment because of jet fuel residue. Kerosene-based fuels will act as solvents when particles come in contact with painted exteriors. While some floor paint formulations are resistant to jet fuel, none is available for coil-coated applications. More to the point, however, is the fact that “resistance” to jet fuel does not equate with “imperviousness.” The InvariMatte® finish is able to make the claim that it is impervious to jet fuel.
Low Glare
In addition to being visually uniform, Contrarian Micro Textures’ InvariMatte® has low reflectivity compared to typical stainless steel finishes. For that reason, it can be used on airports as prominently visible exterior walls and roofs with no risk of glare or reflection that could compromise a pilot’s sight. InvariMatte® has lower gloss (<20 at 85 degrees) than many paint finishes.
Reflectivity is a concern not only for pilots and airport personnel but also for those who live and work in surrounding high-rise buildings and condominiums. “InvariMatte® is a sensible choice as a cladding material in dense urban environments,” said Halliday. “While all stainless steel addresses corrosion and paint failure concerns due to smog and jet fuel residue, some stainless steel finishes are just too bright to be used in glare-sensitive locations like transportation centers.”
Low Life Cycle Cost
Considering the high cost of service disruption at an air terminal, not to mention security issues, a permanent stainless steel roof system is a logical and cost-effective choice. While titanium will perform beautifully from a sustainability standpoint, it can be expensive in comparison to stainless steel. Likewise, a less costly alternative, aluminum, painted or not, requires maintenance or replacement at some point during its lifecycle, which makes it more costly overall.
The appropriate grade of InvariMatte® stainless steel can be expected to last the useful life of an air terminal building with little maintenance. Gutters should be kept clear and panels may need to be cleaned for cosmetic reasons, but these are minimal necessities as compared to alternative products.
Airport Projects
Contrarian Micro Textures’ stainless steel matte finish, InvariMatte®, is being used for the 280,000-square-foot roof during phase one of a terminal project at Raleigh-Durham International Airport—and it will be used for another 107,000 square feet of roof for phase two.
This $570-million project follows the announcement in November 2007 that Contrarian’s InvariMatte® finish is being used in the construction of what will become the world’s largest stainless steel roof at the New Doha International Airport in the State of Qatar.
The new Doha airport will partially open in 2009—with completion set for 2015. At 2.1 million square feet, the new roof will exceed in size the currently largest stainless steel roof of the Kuala Lumpur International Airport (1.614 million square feet).
Contrarian Micro Textures’ stainless steel finishes have been installed in a wide number of applications, including other airport projects in Dallas-Fort Worth, Atlanta, Detroit, Scottsdale, AZ, and the Jamaica AirTrain JFK Terminal.
Airport projects specify Contrarian Micro Textures’ stainless steel finishes primarily for their aesthetic value, glare resistance, and longevity.
InvariMatte® Black is a non-directional, uniformly textured stainless steel finish with a thin black oxide film designed for use in architectural applications. It can be applied to roofing and wall panels, as well as coping and trim. The black chromium oxide film is produced electrochemically in collaboration with Prismatic Stainless Steel, Division of B&M Finishers, Inc. Unlike paints coatings, the finish is not reactive to ultraviolet light. InvariMatte® Black retains the corrosion resistance of the underlying T304 alloy. InvariMatte® Black is readily welded or soldered. However, exposure to high temperatures will destroy the black oxide film.