Description:

The Department of Materials Science and Engineering welcomes you to its 2015 Fall Colloquium Series.

Location: Tech L361, 4:00pm

Tim Weihs
Johns Hpkins

Exploring the Behavior and Application of Reactive Materials
Reactive materials are being developed and commercialized for a variety of applications ranging from local heat sources for bonding to dispersed heat sources for bio-agent defeat. In all cases the reactive materials are fabricated into an unstable state from which large amounts of energy can be released. This is true for materials that enable formation reactions, reduction-oxidation reactions, and simple combustion reactions. In the first part of the presentation we will review some of the factors that control the initiation and propagation of formation reactions in Ni:Al multilayer foils, and we will compare results from novel in situ studies of phase transformations (XRD and DTEM) with MD simulations. We will also explore current commercial applications in the field of joining, using both formation and reduction-oxidation reactions. In the second part of the presentation we will review the impact of chemistry and geometry on the initiation and combustion of reactive foils and particles, and we will evaluate their use for defeating bio-agents such as Anthrax.

Biography: Timothy P. Weihs is a Professor in the Department of Materials Science and Engineering at the Johns Hopkins University where his research focuses on reactive materials and the mechanical properties of structural materials and biomaterials. His formal education includes a BA degree from Dartmouth College, an ME degree from Thayer School of Engineering, and a PhD in Materials Science and Engineering from Stanford University. Following a NATO Postdoctoral Fellowship in the Department of Materials at Oxford University and a second postdoctoral position in the Chemistry and Materials Science Department at Lawrence Livermore National Laboratory (LLNL), he joined the faculty in the Department of Materials Science and Engineering at Johns Hopkins University in 1995.
In 2002, Professor Weihs took a three-year leave of absence from Johns Hopkins University and Co-founded Reactive NanoTechnologies (RNT). After growing the company to the point of first commercial sales as CEO, Professor Weihs returned to active duty at Hopkins to focus on the research areas noted above. However, he remains an active consultant for Indium Corporation that purchased and now produces the NanoFoil® product in 2009. His awards include an NSF Career Award, a 3M Young Faculty Fellowship, an R&D 100 Award, an Innovator of the Year Award, and the TMS Application to Practice Award.

Description:

The Department of Materials Science and Engineering welcomes you to its 2015 Fall Colloquium Series.

Location: Tech L361, 4:00pm

Martin Harmer
Lehigh University

More information to come soon

Description:

The Department of Materials Science and Engineering welcomes you to its 2015 Fall Colloquium Series.

Location: Tech L361, 4:00pm

Fengnian Xia
Assistant Professor
Yale University

Bridging the Gap: Layered Black Phosphorus for Electronics and Optoelectronics
Black phosphorus recently emerged as a promising new 2D material due to its widely tunable and direct bandgap, high carrier mobility and remarkable in-plane anisotropic electrical, optical and phonon properties. It serendipitously bridges the zero-gap graphene and the relatively large-bandgap transition metal dichalcogenides such as molybdenum disulfide (MoS2). In this talk, I will first cover the basic properties of few-layer and thin-film black phosphorus, followed by a discussion of recent observation of highly anisotropic robust excitons in monolayer black phosphorus. Finally I will present a few potential applications of black phosphorus such as radio-frequency transistors and wideband photodetectors.

Biography: Fengnian Xia received the B.S. degree with highest honor in electronics engineering from Tsinghua University, Beijing, China, in 1998 and M.A. and Ph.D. degrees in electrical engineering from Princeton University, Princeton, NJ, USA in 2001 and 2005, respectively. He joined IBM Thomas J. Watson research center in Yorktown Heights, NY, USA as a postdoc in March 2005, and was a Research Staff Member before he started at Yale University as an assistant professor in September 2013. His current research focuses on nanophotonics and nanoelectronics using emerging materials such as graphene, transition metal dichalcogenides, and black phosphorus. He is also actively pursuing carrier transport and light-matter interaction research in dimensional systems.

He received an IBM corporate award, three IBM research division level awards, and numerous IBM invention achievement awards. In 2011, Dr. Xia was selected by MIT technology review magazine as a top young innovator under the age of 35. He received the 2015 Young Investigator Award from the Office of Naval Research (ONR-YIP).

Description:

The Department of Materials Science and Engineering welcomes you to its 2015 Fall Colloquium Series.

Location: Tech L361, 4:00pm

Felice Frankel
MIT

More than Pretty Pictures: Representations that communicate and clarify your thinking.

More information Coming soon