Seeking the perfect finish for stainless steel surfaces

Although Gert Weiß’s experience dates much further back than the start of his Outokumpu career, he has an unequalled understanding of customers’ expectations when it comes to high-quality stainless steel surfaces. In 1988 Weiß came to Krupp Stahl AG gaining expertise in the manufacture of stainless steel strip and specializing in high-quality surfaces for sophisticated customer requirements. Krupp Stahl AG later merged to form ThyssenKrupp Nirosta GmbH, which since 2013 has belonged to Outokumpu.   

Visual messager
In 1989 Weiß was involved in the production of stainless steel strip intended for the façade cladding of the Plaza Tower in Costa Mesa, California. “The main focus of that work was to investigate the influence of production methods on surface quality,” says Weiß. “I have been involved in a large number of architectural projects, and very intensely in the recently completed One World Trade Center in New York City.” He has thought at length about stainless steel, not only from the point of view of its functional properties, but also from the perspective of the visual messages it conveys as a building material.

“Stainless steel surface has two main functions,” he says. “First, it is technically functional in terms of corrosion resistance, wear resistance, and easy maintenance and cleanability. However, quite often it is the emotional and aesthetic aspect of stainless steel that comes to the foreground. Material selection for a tank or a tube in a technical plant is carried out on an entirely rational level to satisfy technical and economic requirements, and certainly these criteria are also important say for the making of an elevator. In addition, there are demands to achieve an appealing appearance. The surface finish of a range hood, for instance, determines the value of this kitchen appliance.”   

High quality and long lasting value
"The question of aesthetics is especially central when designing and choosing the façade cladding of a prestigious building," says Weiß. Technical considerations such as corrosion resistance, processability and a long life cycle are part and parcel of stainless steel as a building material; for façade cladding, a more critical consideration is an outstanding surface finish. “Stainless steel can communicate high quality and long-lasting value in a prominent fashion,” he says.

“Outokumpu offers a wide range of surface finishes, from super matte to mirror bright, from rough to smoother-than-ever,” he continues. “Over many years our engineers have increased and optimized their know-how about optical impact and producing a top-quality surface. This enables us to realize customized stainless steel surfaces for the most challenging applications and projects.”

A feel for steel
In terms of technical requirements, all producers of stainless steel strip are in competition with one another, says Gert Weiß. “In addition to functionality, price is decisive. Increasingly aspects such as a long life cycle  and no maintenance are becoming more important, too.”

On the other hand, he explains, when it comes to products that sell on the basis of their special, specific appearance, criteria are defined differently. “These trends are led by designers and architects,” he says. “More and more we find natural, honest materials requested, materials with high quality and high value. At the moment we can recognize a trend toward matte surfaces with a discernible yet small amount of reflectivity that provides a touch of optical liveliness. We still need to carry out a lot of research and development in this field.”

Ultimately, the customer is all-important. “Definitely, the direction for further development is going to be determined by our customers. But when it comes to realizing their ideas, we are their first point of contact. We have the creativity and production know-how required.”