Engineering Commons^™

Transport Of Nanoparticles In Polyelectrolyte Solutions As A Model Of Polymer Nanocomposite Processing, Jacinta Conrad, Ryan Poling, Firoozeh Babaye, Ramanan Krishnamoorti

Composites at Lake Louise (CALL 2015)

The transport properties of nanoparticles in complex confined media play a significant role in the processing of advanced polymer nanocomposites. In polymer nanocomposite processing, nanoparticles suspended in polymer resins must be efficiently dispersed to obtain optimal mechanical, electrical, thermal, and/or optical properties and eliminate stress concentrators. Here, we investigate the diffusion and dispersion of nanoparticles in solutions of unentangled polyelectrolytes as a model system in which to understand the coupling between particle and polymer dynamics in flow conditions representative of those encountered during nanocomposite processing.

First, we measure the long-time quiescent diffusivity of fluorescent polystyrene nanoparticles in dilute and semidilute …

Fundamental Nanomechanic Investigations Using Combinatorial Deposition Techniques, Rachel Schoeppner, Aidan Taylor, Jakob Schwiedrzik, Gaurav Mohanty, Vipin Chawala, Lazlo Petho, Keith Thomas, Johannes Zecher, Carlos Guerra-Nuñez, Johann Michler

Nanomechanical Testing in Materials Research and Development V

Combinatorial materials design of thin films allows for the investigation of broad ranges of both thickness and composition within a single sample; this can be utilized both for fundamental nanomechanics investigations and for the optimization of thin films for engineering applications. Using a unique self-constructed deposition chamber that combines magnetron sputtering, e-beam evaporation, nanoparticle deposition and atomic layer deposition (ALD), the architectural design of thin films can be tailored to study multiple physical and chemical properties.

Recent investigations have focused on using this chamber’s unique ability to create a gradient composition film of up to three different materials with a …

Deformation Mechanisms Of Twinned Nanoparticles And Nanowires, Erik Bitzek, Wolfram Nohring, Andreas Kelling, Cynthia Volkert

Nanomechanical Testing in Materials Research and Development V

The plastic deformation of nanoscale metallic specimens has recently attracted a lot of interest due to the reported changes of deformation mechanisms with reduced size. Similarly, the interaction of dislocations with twin boundaries has received lots of attention in the context of the ultrahigh strength and ductility of nanotwinned metals. Here, we present experiments and atomistic simulations of compression test on twinned gold nanoparticles to study dislocation processes and -storage in nanosized volumes and dislocation-twin interaction mechanisms and compare them with the deformation behavior of twinned silver and gold nanowires.

Compression experiments were performed on triangular shaped, facetted particles using …

Mechanical Response Of Face-Centered Cubic Metallic Nanospheres Under Uniaxial Compression, Selim Haj Salah, Celine Gerard, Laurent Pizzagalli

Nanomechanical Testing in Materials Research and Development V

The mechanical response of metallic nanoparticles has recently attracted a lot of interest due to their specific properties compared to their bulk counterpart, which allow for novel applications in various fields, e.g., composite materials, nanomanufacturing/nano-electromechanical systems. We have employed Molecular Dynamic simulations to study the mechanical behavior of face-centered cubic metallic nanoparticles. Uniaxial compression of monocrystalline nanosphere is investigated using the EAM potentials developed by Mishin et al. [1] [2]. The resulting behaviors vary with nanoparticle size, crystallographic orientation, and temperature. This work shows that the elastic modulus of metallic nanoparticles is higher than that of the bulk material. Three …