| The description of many technologies relies upon the development of an integrated, multiscale model, which can accurately describe physical phenomena over a broad range of time and length scales. In this dissertation, we adopt a bottom-to-top multiscale methodology in which information is passed from the highest resolution models to the lower resolution descriptions which approach the most relevant system scales. Our work incorporates both of these components and explores techniques for achieving a holistic multiscale description that will produce advancement in technology which is beyond the capability of disparate, disconnected models. We utilize benchmark examples in nanoscale tribology and technology to demonstrate the necessity of the multiscale methodology in modeling material and system performance. Nanotribology is concerned with the friction, lubrication, and wear characteristics of systems which have been engineered at the nanoscale, and the complexity of these tribological systems make them excellent examples of the capabilities of our multiscale approach. The first of these examples is the head-disk interface (HDI) in hard disk drives where the protective lubricant and carbon overcoat (COC) layers are engineered to protect the magnetic data storage layer while satisfying dimensional constraints. The second benchmark example is a study of the frictional response of atomically thin solid materials as a function of the number of layers, with a particular emphasis on graphene and its frictional response. This analysis reveals the dimensional crossover between the 2D and 3D characteristics of the materials.;We conclude with an overview of our contributions to atomistic/molecular scale modeling of our benchmark examples as well as a proposal for extending our multiscale modeling work. In addition an alternative middle-out multiscale methodology, we will apply our techniques to other engineering examples, particularly sustainable energy systems. Thus, we demonstrate the generality and flexibility of our multiscale technique for exploring future engineering challenges. |
