A comprehensive shape memory materials database (SMMD) repository is being developed that provides access to a large collection of information on shape memory materials (SMMs) in a single source. The collection of point data and metadata provides insight into actuation properties, structural performance, chemical data, processing records, and similar factors pertinent to shape memory alloys, polymers, and ceramics. The data is organized in a 2D and 3D visualization platform allowing users to gain immediate access to data insights and trends with only a few button clicks. All data points have full traceability to the original source to verify findings and create a link to researchers and scientists within the community. In addition to millions of datapoints already displayed, the web-application also offers access to analysis tools, references to international standards, and resources pertinent to the SMM community.

This presentation reports on work to create user friendly software to aid in automated data analysis of tests to characterize the shape memory response of alloys. This effort has developed and produced software capable of automated analysis of test data produced using standard test methods and variations of these methods. This software provides a uniform method for analyzing data, which reduces analysis time and reduces error/variation due to different user and organization analysis methods. The software will allow analyzed data to be reported in the ASTM format for material certification, or as compiled data that can be directly imported into the NASA Shape Memory Material Database.

In this paper, the results of different selected mechanical and electrolytic preparation methods are compared with regard to the successful visualization of Nitinol microstructure. The results indicate that a commonly specified preparation route may result in false microstructure and therefore in false interpretation of the material, its behavior, and its lifetime condition. An electrolytic preparation is defined that may provide superior metallographic sample preparation results for drawn NiTi materials.

Standard test methods for Uniaxial Constant Force Thermal Cycling (UCFTC) and Uniaxial Pre-strain and Free Recovery (UPFR) have been published under ASTM as E3097 and E3098, respectively. These two test methods capture the two most important responses in shape memory alloys (SMAs) for actuation, which is load-biased shape memory effect and classical shape memory effect. These test methods measure the transformation properties such as transformation temperatures, actuation strain, and residual strain to provide data for the characterization and selection of SMA materials, quality control, design allowables, and actuator design. In light of this recent development, additional test methods are still needed to fully support the transition of SMA actuators to production use. First, there is a recognized need for a test method that defines and evaluates the evolution of actuation properties and actuation lifecycle during repeated UCFTC. Second, rotary SMA actuation has been demonstrated as a practical and valuable actuator form as highlighted recently during flight test of the spanwise adaptive wing and reconfigurable vortex generators and in remote controlled actuated wind tunnel models. To this end, two new test methods have been proposed to ASTM that extend the applicability of E3097 to repeated UCFTC and torsional testing, respectively. This paper provides an update on the development of SMA standardized test methods for actuator applications highlighting their need and envisioned approaches.