Metal Additive manufacturing (AM) processes build 3D objects by heating and consolidating material in a point-by-point manner. Unlike traditional manufacturing methods, AM allows the material properties of each point in the build to vary by controlling process conditions locally. The process parameters can be considered as inputs to the AM...
Understanding structure-property relationships for polymer nanocomposites is one of the primary challenges in discovering new, light weight, multifunctional advanced materials. Polymer nanocomposites are a class of advanced materials comprised of soft polymer matrix and nano-filler inclusions. While it has been found qualitatively that enhancements of material properties could be achieved...
Lubrication is the most means for sliding interface failure prevention because it helps separate two interacting surfaces, reduce asperity contacts and thus extend the working life of the parts. Improving the tribological performance of lubricated interfaces is a challenging work, as several influence factors are involved, such as coating, plasticity,...
Global energy demand is increasingly rapidly in today’s modern world with increasing living standards all around the world. As global energy demand rises, energy efficiency has never been more crucial and that the improvement of tribological systems is critical to the progress of the global future. A large part of...
Polymer nanocomposites have attracted great interest in recent years because of their potential as tailored materials with enhanced properties. Recent experiments have shown that polymer nanocomposites are able to achieve significant improvement in dielectrical, thermal, mechanical and other physical properties compared with their parent polymer systems. More importantly, these outstanding...
Polymer nanocomposites are a class of advanced materials comprised of soft polymer matrix and nano-filler inclusions. While it has been found qualitatively that enhancements of material properties could be achieved by dispersing inorganic nano-particles into organic polymer matrix, the intrinsic governing principles of such composite has not been thoroughly studied...
Nanoelectromechanical (NEMS) systems fabricated using atomically-thin materials have low mass and high stiffness and are thus ideal candidates for force and mass sensing applications. Transition metal dichalcogenides (TMDCs) offer certain unique properties in their few-layered form – such as piezoelectricity and a direct band gap in some cases – and...
The dissertation systematically delineates the mechanically-guided deterministic assembly of three-dimensional (3D) mesostructures by compressive buckling, covering topics from mechanics concepts, design and analysis, fabrication techniques, to application opportunities. The development of approaches to form complex 3D functional mesostructures in advanced materials is a topic of broad interest, thanks to the...
To relate the mechanical responses of hard-soft copolymer systems with their microstructures, a coarse-grained molecular dynamics (CGMD) approach is employed. With the generic bead-spring polymer model mapped from atomistic simulations, this dissertation first studies the morphology of structures with various hard-soft compositions and interactions between hard beads. Following that, this...
The presence of unwanted biofilms on surfaces is a great concern for industrial, naval, and healthcare fields, and many other settings. To better inhibit, remove, or harness the properties of biofilms, an explanation of how specific structural or chemical features of biofilm matrix components leads to enhanced adhesion and persistence...