Mechanical Size‐Effects in Miniaturized and Bulk Materials

Abstract Interfaces and surfaces can impose substantial mechanical size‐effects on materials. The deformation mechanisms become increasingly constrained when microstructural and/or geometrical dimensions decrease. This effect can improve, for example, the creep resistance of a bulk lamellar material, but it may cause failure for a miniaturized material component due to high internal stresses. Several dislocation mechanisms causing size‐dependent flow stresses for (sub)micron‐sized metals and metallic thin films are addressed in this paper and the current understanding of size‐effects in miniaturized and bulk materials is reviewed. The beneficial application of mechanical size‐effects is demonstrated for TiAl alloys and nanostructured hard coatings.