| Characterization of Nickel-Rich Nitinol Alloys for Actuator Development | ||
| Mr. James Mabe1, Dr. Frederick T. Calkins2 and Dr. Robert T. Ruggeri3, 1Phantom Works, The Boeing Company, PO Box 3707, M/C 4A-51, Seattle, WA 98124, 2The Boeing Company, PO Box 3707, Seattle, WA 98124, 3Phanton Works, The Boeing Company, PO Box 3707, Seattle, WA 98124
Recently a nickel-rich NiTinol alloy was used to fabricate compact, lightweight, and robust SMA actuators for a flight test of morphing aerostructures. Chevrons are serrated aerodynamic devices along the trailing edge of a jet engine that have been shown to reduce jet noise. In 2005 Boeing successfully flight-tested morphing chevrons on a Boeing 777-300ER with GE-115B engines. In this paper the properties and characteristics of the Ni-40Ti (% by weight) alloy used for the flight test actuators are compared to those of Ni-45Ti and Ni-48Ti. The mechanical properties, transition temperatures, creep, 2-way shape memory effect, and the response to various heat treatments are reported for each alloy. The suitability of the nickel-rich alloys for actuator development is demonstrated using performance data from the flight test. The unique properties of the nickel-rich alloys, including material reliability and transition temperature stability, are shown to be invaluable to the successful development of morphing aerostructures. | ||