Mechanical properties of selected nanostructured materials and complex bio-nano, hybrid and hierarchical systems

Abstract

Fundamental investigations into mechanical behaviour and properties, e.g. elasticity, plasticity, hardness, toughness, strength and failure, exhibited at the nanoscale have increased rapidly in number and in breadth over the past two decades as experimental techniques and theoretical treatments have advanced. This review covers selected contemporary nanomechanics research and gives an overview of some fundamental questions, measurement challenges and opportunities concerning nanostructured materials, their mechanical properties and deformation mechanisms – particularly, relationships with size-scale phenomena. Significant theoretical developments are mentioned in relevant sections and advances in computational modelling are considered briefly, including perspectives on the current state and gaps between complete and rigorous simulations for mechanical behaviour in nanomaterials and experimental data to qualify certain predictive calculations. We categorise the study of mechanics by nanomaterial types from primary objects (i.e. single nanoscale elements like nanofibres and nanopillars), simple composites and other extended nanostructures like films and multilayers to complex natural and synthetic systems ranging from biological cells and mineralised biocomposites to nanoelectromechanical systems and DNA nanorobots. The future outlook and concluding remarks summarise general areas of open knowledge in the field and include a call for increased collaboration between experiments and modelling for the fruition of twenty-first century advancements and exploration.

Keywords:

• Nanomaterials
• Mechanical properties
• Nanomechanics
• Size-scale effects
• Ultra-strength
• Deformation mechanisms

The authors gratefully acknowledge research funding from the W. M. Keck Foundation that allowed pursuit of initial interests in nanomechanics more than a decade ago, and other historical support from the National Science Foundation (DMR-0619310), the NSF-Idaho EPSCoR Program (EPS-0132626 and EPS-0447689), the University of Idaho Biological Applications of Nanotechnology (BANTech) Center and the Idaho Research Council, all of which partially supported continuing research projects concerning the mechanical behaviour of nanowires, nanofibres and nanosprings, and their applications over the past 11 years.