IMPLEMENTATION OF HSLA-100 STEEL IN AIRCRAFT CARRIER CONSTRUCTION - CVN 74

High strength low alloy (HSLA)-100 steel was developed to be less sensitive to hydrogen embrittlement than high yield (HY)-100 steel. The primary benefits sought through the use of this new steel were savings in energy, labor, and scheduling that would result from reduced preheat for welding. This paper reviews the overall efforts required to implement the use of HSLA-100 steel during CVN 74 aircraft carrier construction. It discusses the engineering and design effort required to incorporate a new material on a vessel midway through construction. Also included is a discussion of the development of an implementation plan which ensures successful welding procedure qualification, production welding, and inspection of HSLA-100 welds. Results confirm that HSLA-100 steel can be successfully substituted for HY-100 steel in a shipyard environment, and that significant benefits can be realized from reduced welding preheat. Also, key elements of future applications of HSLA-100 are presented