- Shape memory alloys (SMAs) are widely used as actuators in many high tech applications from heart stints to aircraft. Recently the ASL discovered a previously unreported property of Nickel Titanium SMAs that could make them even more useful in more applications. The ASL is continuing research to explain the nature and origion of the property.
- Shape memory alloys can under go large, recoverable deformations in their low temperature, martensitic state. When heated the materials undergo a reversible phase transformation to an austenite crystalline structure and try to return to their parent geometry. When cooled back to a martensite state the SMA will stay in its parent geometry unless loaded to deform again. The ASL discovered that, when a SMA is mechanically constrained from returning to its parent geometry in the austenite state, and cooled to its martensite state, it will produce a “post constrained recovery residual stress” (PCRRS) that does not depend upon continued thermal actuation.
- Explore and understand the origin and nature of PCRRS.
- Create new theory to explain PCRRS.
- Muhammad Istiaque Haider
- Masum Bellah
- Nathan Salowitz
- Haider, Muhammad Istiaque; Salowitz, Nathan; “Mechanics of post constrained recovery residual stress produced by NiTi” in Proceedings of ASME Smart Materials, Adaptive Structures and Intelligent Systems 2019, Louisville, Kentucky, September 9 – 11, 2019
- Haider, Muhammad Istiaque; Rezaee, Maysam; Salowitz, Nathan; “Investigation into Post Constrained Recovery Properties of Nickel Titanium Shape Memory Alloys” Smart Materials and Structures, online 8/13/2019
- Salowitz, Nathan; Correa, Ameralys; Santebennur, Trishika; Moghadam, Afsaneh; Yan,Xiaojun; Rohatgi, Pradeep; “Mechanics of nickel–titanium shape memory alloys undergoing partially constrained recovery for self-healing materials” Journal of Intelligent Material Systems and Structures, vol. 29, issue 15, pp 3025-3036, 6/18/2018, https://doi.org/10.1177/1045389X18781260
- Haider, Muhammad Istiaque; Correa, Ameralys; Moghadam, Afsaneh; Yan, Xiaojun; Salowitz, Nathan “Experimental Exploration of Post Constrained Recovery Mechanics of NiTi” in Proceedings of ASME Smart Materials, Adaptive Structures and Intelligent Systems 2018, San Antonio Texas, September 10 – 12, 2018
- Kilicli, Volkan; Yan, Xiaojun; Salowitz, Nathan; Rohatgi, Pradeep; “Recent Advancements in Self-Healing Metallic Materials and Self-Healing Metal Matrix Composites” JOM (The Journal of The Minerals, Metals & Materials Society) 4/2/2018
- Salowitz, Nathan; Kilicli, Volkan; Yan, Xiaojun; Rohatgi, Pradeep K., “Recient Developments in Self-Healing Metallic Materials and Mechanics of Self Healing Composites,” in Contributed Papers from Materials Science & Technology 2017, Pittsburgh, PA, 2017, pp. 201-203.
- Salowitz, Nathan; Moghadam, Afsaneh; Correa, Ameralys; ”Mechanics of NiTi Reinforced Self-Healing Materials Producing Crack Closing Loads”, Proceedings of ASME Smart Materials, Adaptive Structures and Intelligent Systems 2017, Snowbird Utah, September 18 – 20 2017, http://proceedings.asmedigitalcollection.asme.org/proceeding.aspx?articleID=2663087
- Correa, Ameralys; Dorri, Afsaneh; Rohatgi, Pradeep; Salowitz, Nathan” Mechanics and design of self-healing materials to complement SHM” Invited Paper, Structural Health Monitoring 2017, Stanford University, September 12 – 14 2017
- Salowitz, Nathan; “Mechanics & Analysis of Self-Healing Materials” The Engineering Mechanics Institute Conference, UC San Diego, June 4-7 2017
- Salowitz, Nathan; Correa, Ameralys; Moghadam, Afsaneh; Rohatgi, Pradeep; “Mechanics based design and testing of crack closing self-healing materials to carry external loads” Invited contribution In Proceedings of the 3rd International Conference on Smart Materials & Structures, Orlando Florida 3/20/2017
- Suri, Shvetashva; Correa, Ameralys; Rohatgi, Pradeep; Salowitz, Nathan; “Initial integration of ultrasonic structural health monitoring of self-healing materials,” in Proceedings of the 8 European Workshop on Structural Health Monitoring, Balboa, Spain, 2016. http://www.ndt.net/events/EWSHM2016/app/content/Paper/129_Salowitz.pdf
This research has been supported by:
- Funds provided by The University of Wisconsin – Milwaukee