(Current Sponsor: NASA Early Career)

 

Novel complex intermetallic compounds are known to possess unique chemical, electronic, physical, and magnetic properties. Their special atomic arrangements usually lead to interesting mechanical behaviors. In this project, we use (1) solution growth, (2) nanofabrication, (3) nanomechanical tests, and (4) advanced computer simulations (DD, MD, DFT) for fundamental understanding of mechanical behavior of novel intermetallic compounds.

Solution growth method is an excellent way to grow various kinds of single crystalline metallic compounds with a millimeter length scale, compared to Bridgman or Czochralski methods. Thus, this growth method is adequate for academic studies. With the right choice of composition and temperature (based on a phase diagram), a single crystalline intermetallic compound can be grown in a high temperature solution, and can be extracted by rapid decanting process. Then, focused-ion-beam (FIB) milling is used to fabricate nano-/micro-pillar with different sizes and orientations for nanomechanical tests. Both ex-situ and in-situ nano-nanoindentation systems are used to obtain stress-strain data and to understand their mechanical behavior at small length scales. Advanced computation simulations are also used to understand the details of deformation mechanisms.

Collaboration Efforts

• Single crystal growth: Dr. Paul C. Canfield’s research group at the Department of Physics at Iowa State University
• Computer simulation (DFT): Dr. Christopher R. Weinberger’s research group at the Department of Mechanical Engineering at Colorado State University
• Computer simulation (DFT): Dr. Roser Valentí’s research group at Institut für Theoretische Physik at Goethe University.
• Transmission electron microscopy: Dr. Mark Aindow’s research group at the Department of Materials Science and Engineering at University of Connecticut

 

< Solution Growth of Single-Crystalline Intermetallic Compound >

Please enjoy Prof. Paul Canfield (Physics, Iowa State Univ)’s excellent description of solution growth of single crystals.

(1) Solution growth of intermetallic compounds: A Beginner’s Guide

(2) Design and Growth of Novel Materials

<Photos of some intermetallic compound single crystals>

 

<Giant Superelasticity of [0 0 1] CaFe2As2>

This intermetallic compound exhibits ~14% of elastic strain under compression through reversible phase transition between tetragonal and collapsed tetragonal phases at room temperature.

(John T. Sypek et al., “Superelasticity and cryogenic linear shape memory effects in CaFe2As2,” Nature Communications 8 1083 (2017))

<Giant Superelasticity of [0 0 1] CaKFe4As4>

This intermetallic compound exhibits ~17% of elastic strain under compression through reversible phase transition between tetragonal and half-collapsed tetragonal phases at room temperature.

(Gyuho Song, et al., “Ultrahigh elastically compressible and strain-engineerable intermetallic compounds under uni-axial mechanical loading,” APL Materials 7, 061104 (2019))

 

Related Publications

1. Juan Schmidt, Aashish Sapkota, Carcyn L. Mueller, Shuyang Xiao, Shuyuan Huyan, Tyler. J. Slade, Raquel A. Ribeiro, Seok-Woo Lee, Sergey L. Bud’ko, Paul. C. Canfield, “Tuning the structure and superconductivity of SrNi2P2 by Rh substitution,” Physical Review B 111, 054101 (2025) [PDF][web].
2. Shuyang Xiao, Adrian Valadkhani, Sarshad Rommel, Paul Canfield, Mark Aindow, Roser Valentí, Seok-Woo Lee, “Tension-compression asymmetry in superelasticity of SrNi2P2 single crystals and the influence of low temperatures,” Acta Materialia, 274, 119989 (2024) [PDF][web]
3. Shuyang Xiao, Sarshad Rommel, Kiera A. Burns, Aurora A. Buswell, Vladislav Borisov, Juan Schmidt, Roser Valentí, Paul C. Canfield, Mark Aindow, Seok-Woo Lee, “Effects of Rhodium doping on dislocation nucleation in a [001] SrNi2P2 single crystals under spherical nanoindentaiton,” Journal of Materials Research, 38, 3491–3503 (2023) [PDF][web] (Kiera A. Burns and Aurora A. Buswell are UConn undergraduate students!).
4. Shuyang Xiao, Vladislav Borisov, Guilherme Gorgen-Lesseux, Sarshad Rommel, Gyuho Song, Jessica M. Maita, Mark Aindow, Roser Valentí, Paul Canfield, Seok-Woo Lee, “Pseudoelasticity of SrNi2P2 micropillar via lattice collapse and expansion,” Nano Letters, 21, 7913-7920 (2021) [PDF] [web] 
5. Gyuho Song, Vladislav Borisov, William R. Meier, Mingyu Xu, Keith J. Dusoe, John T. Sypek, Roser Valenti, Paul C. Canfield, Seok-Woo Lee, “Ultrahigh elastically compressible and strain-engineerable intermetallic compounds under uni-axial mechanical loading,” APL Materials 7, 061104 (2019) [PDF] [web]
6. Ian N. Bakst, Keith J. Dusoe, Gil Drachuk, James R. Neilson, Paul C. Canfield, Seok-Woo Lee, Christopher R. Weinberger, “Effects of point defects on the mechanical response of LaRu2P2,” Acta Materialia 160 224-234 (2018) – [PDF][web]
7. Ian N. Bakst, Hang Yu, Mohammadreza Bahadori, Haibo Yu, Seok-Woo Lee, Mark Aindow, Christopher R. Weinberger, “Insights into the plasticity of Ag3Sn from Density Functional Theory,” International Journal of Plasticity 110 57-73 (2018) – [PDF][web]
8. Ian N. Bakst, John T. Sypek, Seok-Woo Lee, James R. Neilson, Christopher R. Weinberger, “Modeling pseudo-elastic behavior in small-scale ThCr2Si2-type crystals,” – Computational Materials Science 150, 86-95 (2018) [PDF][web]
9. Keara Frawley, Ian Bakst, John T. Sypek, Sriram Vijayan, Christopher R. Weinberger, Paul C. Canfield, Mark Aindow, Seok-Woo Lee, “A nanoindentation study on plastic deformation and fracture behaviors of [0 0 1] CaFe2As2 intermetallic compound,” JOM 70, 1074-1080 (2018) [PDF][web] – Keara Frawley (undergraduate student) –  featured in journal cover
10. Gyuho Song, Tai Kong, Keith J. Dusoe, Paul C. Canfield, Seok-Woo Lee, “Shear localization and size-dependent strength of of YCd6 quasicrystal approximant at the micrometer scale,” Journal of Materials Science 53, 6980-6990 (2018) [PDF][web]
11. Haibo Yu, William Meier, Paul C. Canfield, Christopher R. Weinberger, Seok-Woo Lee, Mark Aindow, “Defect structures in solution-grown single crystals of the intermetallic compound Ag3Sn,” Journal of Materials Science 53, 5317-5328 (2018) [PDF][web]
12. Haibo Yu, Yu Sun, Seok-Woo Lee, Paul C. Canfield, Mark Aindow “Characterization of Dislocations in Single-Crystalline Ag3Sn intermetallic alloys,” Proceedings of Microscopy and Microanalysis, 23 760-761 (2017) [PDF] [web]
13. John T. Sypek, Hang Yu, Keith J. Dusoe, Gil Drachuck, Hetal Petal, Amanda M. Giroux, Alan I. Goldman, Andreas Kreyssig, Paul C. Canfield, Sergey L. Bud’ko, Christopher R. Weinberger, Seok-Woo Lee, “Superelasticity and cryogenic linear shape memory effects of CaFe2As2,” Nature Communications 8 1083 (2017) [PDF][web]– Featured at Ames Laboratory News, Science Daily, UConn, UConn Today, phys.org.
14. John T. Sypek, Christopher R. Weinberger, Sriram Vijayan, Mark Aindow, Paul C. Canfield, Seok-Woo Lee, “Superelastic and micaceous deformation in the intermetallic compound CaFe2As2,” Scripta Materialia 141 10-14 (2017) – [PDF][web].