Development of High-Temperature Shape Memory Alloys for Aerospace Applications

Abstract of Proiect and Description of NASA Exploration CoUaboration We propose a combined characterization/modeling approach to develop, characterize and model NiTiHf High Temperature Shape Memory Alloys (HTSMAs). Our aim is to construct transformation temperature vs. composition phase graphs of NiTiHf alloys, characterize and identify the effects of composition and thermomechanical treatments on shape memory and material properties to improve and tailor the high temperature shape memory behavior in terms of material strength, transformation strain, creep, plastic deformation and cyclic stability, and develop a phenomenological model calibrated by experimental findings. The key outcomes from the proposed research are identified as (1) a deeper understanding on the effects of composition and thermomechanical treatments on the microstructure, overall shape memory and plasticity characteristics of HTSMAs; (2) development of the phenomenological SMA model which captures the high temperature behavior of HTSMAs (3) initiate a strong partnership between NASA-Glenn center researchers and University of Kentucky (4) increase awareness of HTSMA research at University of Kentucky, (5) form a strong research infrastructure and multi-investigator team to propose projects for competitive funding from NASA and/or other federal sources on HTSMAs. With this study, a strong collaboration between NASA-Glenn researchers and University of Kentucky faculty will be established. Expertise of NASA-Glenn researchers on high temperature shape memory alloy development and high temperature plasticity modeling will be used, and one the students working on this project will visit NASA research centers for materials testing and characterization.