the ultimate goal of this work is to: 1) fabricate inexpensive mmsmas in polycrystalline bulk form...

• The ultimate goal of this work is to: 1) fabricate inexpensive MMSMAs in polycrystalline bulk form having large magnetic field‐induced actuation work output and significantly enhanced ductility using a powder metallurgy (PM) approach, and 2) fabricate open porous MMSMAs for the evaluation of their biological viability and potential as remotely controlled active MMSMA tissue scaffolds for in‐vitro osteogenesis.

• The intellectual merits of this transformative research are:– The potential to create an entirely new family of tissue scaffolds, i.e. meta‐

magnetic tissue scaffolds, from open porous MMSMAs that would allow far-field actuation for tissue growth in‐vitro & in‐vivo.

– The potential to revolutionize the field of SMAs and actuator materials by fertilizing completely new property landscapes and theories on magneto-thermo-mechanical coupling

– Improved MMSMA ductility and fracture toughness through unique processing techniques thereby making MMSMAs cheaper and more accessible for a multitude of applications.

• Research Highlights:– Demonstrated for the first time in the world that a porous polycrystalline meta-

magnetic SMA can be created through pressureless sintering. This sintering technique produces small pores at the triple junctions that improve intergranular compatibility. It allowed the first polycrystalline MMSMA (NiMnCoAl) exhibiting a superelasticity and metamagnetic shape memory.

– Developed a completely new technique for making porous MMSMAs using magnesium particles as space holder during pressureless sintering. Advantages of using Mg particles: 1) ease of obtaining different size spherical particles, 2) immisibility of Mg in MMSMAs, 3) excellent oxygen reducing ability of Mg .

– Demonstration of stable cyclic mechanical response, magnetic field induced transformation, and meta-magnetic shape memory effect in sintered NiCoMnSn powders with small pores.

– Successful fabrication of 50% porous NiMnCoSn MMSMAs showing magnetic-field induced martensitic transformation.

– Evaluation of the cytotoxicity of MMSMAs such as NiMnSn, NiMnCoSn, NiMnCoAl. They show low biocompatibility, but experiments utilizing a passive layer for improved biocompatibility are currently underway

– Two publications with Japanese collaborators and two articles being prepared for review.

Evolution of the porosity fraction as a function of the sintering time during pressureless sintering of NiCoMnSn

particles. Thermo-mechanical response and magnetic field induced martensitic transformation in porous

NiMnCoSn MMSMAs.

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The large porous microstructure NiCoMnSn from burning out an ammonium bicarbonate space holder and its magnetic response.

Materials World Network: U.S.-Japan Research Collaboration in Meta-Magnetic Shape Memory Alloys (MMSMAs) with Enhanced Ductility and Controlled Porosity

Ibrahim Karaman, Texas Engineering Experiment Station, DMR 0909170

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Collaboration Network

The Broader Impacts of this research are:• Help K-12 students develop science projects with MMSMAs• Development of teaching modules for incorporation into undergraduate courses• Enhanced graduate and undergraduate research experiences through REU students, IGERT program, and international research experience.• Continued and new collaboration with international universities.• Involvement of underrepresented groups.• Disseminating the knowledge generated to both academia and industry through the workshops and symposiums on SMAs, presentations, publications.

Highlights:• Three graduate students (one hispanic male, one white

female and one white male, all U.S. citizens) and one undergraduate student (Hispanic male from the University of Puerto Rico) are employed.

• One research article has been published and two are in review (total of 3).

• Ongoing interaction with students from a local junior high and high school to conduct science projects in the PI’s lab. Two female middle school students attended the International Sustainable Energy, Engineering and Environment Project Olympiad (I-SWEEEP) 2010, with their project on MMSMAs. I-SWEEEP is a science fair open to middle and high school students. It is the largest science fair event of its kind world-wide. Each year, around 500 projects from 70 different countries competes in I-SWEEP (www.isweeep.org)

•Continued work with Tohoku University in Japan and new collaborations with Hacettepe University and Koc University in Turkey.•The two graduate students participated in an SMA workshop in at Koc University in Istanbul and one was awarded first place for the poster presentation competition.• The PI has been active in the ISWEEP Olympiad as judge

and member of the organizing committee. Both the PI and Co-PI have been involved in recruitment activities at Minority Institutions.

• The Co-PI has organized one international symposium and one workshop on SMAs.

HACETTEPE

UNIVERSITY

Materials World Network: U.S.-Japan Research Collaboration in Meta-Magnetic Shape Memory Alloys (MMSMAs) with Enhanced Ductility and Controlled Porosity

Ibrahim Karaman, Texas Engineering Experiment Station, DMR 0909170