Hexavalent Chromium Elimination: An Aerospace Industry Progress Report

he strict corrosion-control requirements in the aerospace inT dustry were developed based on the performance of hexavalent chromium (chromates). With the recent rash of environmental regulations targeting hexavalent chromium, it is reasonable to ask what the industry’s response has been to identify acceptable replacement technologies. Does the aerospace industry take the “ostrich response,” which is to deny the existence of the problem? The “opossum approach,” just acting as if the regulations would be fatal to the industry and hoping they are not enacted, is also tempting. Perhaps the industry favors the “lemming approach,” by which aerospace charges toward the regulatory “cliff’ and assumes a technological breakthrough will bail them out at the last minute. In fact, the aerospace industry’s response has been none of the above. Aerospace has come together on the issue of hexavalent chromium to work toward the objective of complete elimination. This cooperation in the aerospace industry during the past decade has led to numerous successes. The purpose of this article is to review some of these successes and to identify a few areas where additional hexavalent chromium elimination work is required.