Fatigue of Aluminum Structural Weldments

2000Final ReportPDFTech ReportNTIS #PB2000-108442SSC-410SR-1395DTCG39-95-D-E99010Aluminum alloysCoding systemsFatigue crackingFracture mechanicsTolerances (Engineering)DesignMarine engineeringWeldmentsAluminum alloysCodesCostsCracking(Fracturing)Damage toleranceDesignFatigue(Mechanics)Marine engineersRepairShipsWeldingWeldmentsUnited StatesShip Structure CommitteeKramer, R. K.Rampolla, B.Magnusson, A.John J. McMullen Associates, Inc.United States. Ship Structure CommitteeUnited States. Coast GuardUS Transportation CollectionAs the speed and displacement of high-speed aluminum craft continues to increase so to do the fatigue related cracking problems. At present, most owners treat this as a maintenance problem and simply repair the cracked structure. This report attempts to shift the emphasis of this problem from maintenance to design. It will allow owners to address fatigue related cracking problems during the design of the vessel and avoid the costly repairs associated with continued re-welding of fatigue cracked structure. The report addresses loads acting on high-speed craft and identifies the state of the art as well as "holes" in the data required to develop a complete and consistent set of fatigue calculations for aluminum in the marine environment. The report also addresses the damage tolerance of cracked aluminum structure and provides information that will help designers and engineers determine the urgency with which a specific crack may need repair. The report also identifies and provides information on the fatigue design practices of other aluminum industries and design codes. This provides helpful insight while more data is developed for the marine industry and aluminum high-speed craft. The report concludes with recommendations for continued research and development based on the holes identified during the development of the current effort.82