Smaller is Stronger: Exploring the Strange New World of Small-Scale Mechanical Behavior with NanoindentationGeorge M. PharrJoint Institute for Advanced Materials - Department of Materials Science and Engineering
Since its development on the mid-1980's, nanoindentation has proven itself as an important tool for exploring and characterizing the small-scale mechanical behavior of a wide variety of materials. Some of these materials are quite unusual, either because the materials themselves are out-of-the-ordinary or because their mechanical behavior at the micro- and nano-scales is very different from that of the bulk. For example, small pillars of pure metals with diameters less than 1 micrometer can have strengths 10 to 100 times greater than their macroscopic counterparts. In this presentation, a series of examples are used to illustrate some of the unusual properties observed at small scales along with the scientific reasons for them. The examples are taken from a diverse set of disciplines including materials science, biology, geology, and medicine, all of which have benefited enormously from recent advances in nanomechanical testing.