Mechanical behaviors of metallic materials in a small scale are characterized and physically modeled based on experimental measurements and computational simulation. An effect
of in–solution carbon or silicon in Fe on a plasticity initiation was characterizes by nanoindentation pop– in phenomenon. A coherency at a ferrite–cementite interface significantly affects to a
plasticity initiation leading to a different macroscopic yielding behavior. A stability of an austenite phase in TRIP steel was evaluated though the analysis of indentation–induced deformation
behavior, demonstrating a significant constraint effect on stabilization by an adjacent harder phase. Heterogeneous microstructures with a bimodal grain size in fcc metals show an
inhomogeneous mechanical behavior depending on a location of the fine microstructure. An intermittent plasticity in pure iron was analyzed through a statistical model showing a Gaussian
function by thermally activated process in the early stage and a power–law one by an avalanche type phenomenon in the subsequent stage. An elementally step in a plastic deformation in a
metallic glass was characterized through Molecular Dynamics simulation indicating that the plasticity inhomogeneity depends remarkably on the initially inhomogeneous atomistic structure.