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EAGER: Probing Deformation Mechanism Transition of Metals at the Nanoscale Jun Lou, William Marsh Rice University, DMR 1128818. ● Design, fabrication, and application of a novel Si based micromechanical devices (RMD) as mechanical testing platform for metal nanowires
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EAGER: Probing Deformation Mechanism Transition of Metals at the NanoscaleJun Lou, William Marsh Rice University, DMR 1128818 ● Design, fabrication, and application of a novel Si based micromechanical devices (RMD) as mechanical testing platform for metal nanowires ● Demonstration of RMD successful operation inside both SEM and TEM ● Continuous stress-strain curve obtained for metal nanowires along with real time high resolution SEM/TEM observations of deformation and fracture processes ● Demonstrate for the first time the nanoscale defect-free cold-welding of nanowires with superior strength and electrical conductivity in HRTEM ● Demonstrate surface dislocation nucleation mediated deformation and ultrahigh strength ● Demonstrate size dependent deformation mechanism transition The Rice micromechanical device (RMD) is fabricated by bulk micromachining of silicon-on-insulator (SOI) wafers; Back etched window enables TEM compatibility(JMEMS, 2010; Experimental Mechanics, 2010; Nanotechnology, 2011) Lu et al., Nano Research, 2011; Peng et al., Small, 2012; Peng et al., J of Appl. Phys., 2012;
EAGER: Probing Deformation Mechanism Transition of Metals at the NanoscaleJun Lou, William Marsh Rice University, DMR 1128818 ● The research findings were integrated into the graduate course MSCI 650 “Advanced topics on nanomaterials and nanomechanics” taught by the PI to 20 graduate students in spring 2012. ● A special topic discussion session integrating the research activity pursued in this work were also created in an undergraduate course MSCI 402 “Mechanical Behavior of Materials” taught by the PI to 24 students in fall 2011. ● The Rice PI has continued the previously established strong relationship with University of Houston-Downtown, a minority serving institute. The PI’s lab hosted lab tours for UHD professors and students interested in nanoscience and nanotechnology. Two undergraduate students, Mr. Samuel Stein (not pictured) and Miss. Laura Gaskin had worked on related experiments with their graduate mentors and had gained very valuable research experiences through participations in this project.