Sustainable Materials

Stainless steel has been successfully used in building envelopes since the completion of the Chrysler building in 1928. Today, it is used as both a structural material and for skin components. Its corrosion resistant properties give it a long service life, and it requires very little maintenance, making it an ideal material choice in harsh environments. The end of life recyclability is another desirable quality in-today’s buildings. The development of new stainless steel alloys has broadened the design team’s material palette. These higher strength alloys allow components to be designed smaller and from a material that will last forever in almost any condition.

In many cases, the design team’s desire to use state of the art materials has outpaced the experience set of fabricators. As designers and fabricators work together on innovative building components, one area of critical interest is the welding of stainless steels. High performance stainless steels require specialized welding knowledge and more complex, labor-intensive procedures. For example, the long life and aesthetic advantages of commonly used stainless steels can be jeopardized if they are exposed to improper heating and cooling during the welding process. In some cases, the improper welding of high-performance alloys can lead to a severe decrease in corrosion resistance or an increased risk of structural failure.

This paper provides an overview of best practices for common alloys that are covered by AWS D1.6 and a more detailed examination of how design practitioners can ensure that high-performance alloys are treated properly in fabrication. The content will not be overly technical, but it will provide a working knowledge of what is achievable without special testing and an understanding of the development of one-off welding procedures and the qualification of welders for unique materials. A better understanding of the welding metallurgy and behaviors of high-performance alloys will provide designers with the necessary tools for assessing the cost-benefit and inherent risks in these procedures. Designers will learn more about avoiding problems that are expensive to remediate and potentially dangerous. Specific examples of built work will be used to show how these challenges were overcome during the course of design and fabrication.