T. Morri, Remmele Engineering Inc., New Brighton, MN
Demand for titanium alloys in the current generation of fuel efficient, high performance aircraft is projected to exceed industry capacity sometime in the next decade. Development of materials efficient processes and products will be a key factor in insuring the future affordability and availability of strategic materials like titanium. Significant progress has been reported in the development of Friction Stir Welding of titanium alloys. FSW manufacture of near-to-net shape pre-forms has the potential to dramatically improve the ratio of purchased raw material stock to aircraft fly-away weight compared with conventional methods such as machine from plate stock, effectively increasing the net stock of industry mill capacity. This paper will report the results of FSW fabrication trials performed at Remmele Engineering in St. Paul, MN using ATI 425 alloy. ATI 425 is a proprietary alloy developed by Allegheny Technologies Inc. that exhibits both hot and cold workability with equivalent properties to titanium alloys that are typically specified for aircraft structural applications. FSW butt-welded samples will be produced using several sets of process parameters. Preliminary results will be presented and discussed including basic mechanical properties, microstructure analysis and non-destructive inspection.
Summary: This paper will present the results of FSW trials performed at Remmele Engineering in St. Paul, MN using ATI 425 titanium alloy. Test data from samples manufactured using several process parameter sets will be evaluated and discussed including mechanical properties, microstructure analysis and NDI.
