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Experiment and Modeling of Simultaneous Creep, Plasticity and Transformation of High Temperature Shape Memory Alloys During Cyclic ActuationThe present work is focused on studying the cycling actuation behavior of HTSMAs undergoing simultaneous creep and transformation. For the thermomechanical testing, a high temperature test setup was assembled on a MTS frame with the capability to test up to temperatures of 600 C. Constant stress thermal cycling tests were conducted to establish the actuation characteristics and the phase diagram for the chosen HTSMA. Additionally, creep tests were conducted at constant stress levels at different test temperatures to characterize the creep behavior of the alloy over the operational range. A thermodynamic constitutive model is developed and extended to take into account a) the effect of multiple thermal cycling on the generation of plastic strains due to transformation (TRIP strains) and b) both primary and secondary creep effects. The model calibration is based on the test results. The creep tests and the uniaxial tests are used to identify the viscoplastic behavior of the material. The parameters for the SMA properties, regarding the transformation and transformation induced plastic strain evolutions, are obtained from the material phase diagram and the thermomechanical tests. The model is validated by predicting the material behavior at different thermomechanical test conditions.
Document ID
20110014514
Document Type
Conference Paper
Authors
Kumar, Parikshith K. (Texas A&M Univ. College Station, TX, United States)
Desai, Uri (Texas A&M Univ. College Station, TX, United States)
Chatzigeorgiou, George (Texas A&M Univ. College Station, TX, United States)
Lagoudas, Dimitris C. (Texas A&M Univ. College Station, TX, United States)
Monroe, James (Texas A&M Univ. College Station, TX, United States)
Karaman, Ibrahim (Texas A&M Univ. College Station, TX, United States)
Noebe, Ron (NASA Glenn Research Center Cleveland, OH, United States)
Bigelow, Glen (NASA Glenn Research Center Cleveland, OH, United States)
Date Acquired
August 25, 2013
Publication Date
April 12, 2010
Subject Category
Structural Mechanics
Report/Patent Number
E-17849
AIAA Paper 2010-2992
Meeting Information
51st AIAA/ASME/ASCE/AHS/ASC Structures, Sturctural Dynamics and Materials Conference(Orlando, FL)
Funding Number(s)
CONTRACT_GRANT: NNX07AB56A
WBS: WBS 561581.02.08.03.15.13
Distribution Limits
Public
Copyright
Other