6533b838fe1ef96bd12a3a87

RESEARCH PRODUCT

Size effects in micro- and nanoscale indentation

Jānis ManiksI. Manika

subject

Materials sciencePolymers and PlasticsMetals and AlloysWork hardeningNanoindentationCondensed Matter::Disordered Systems and Neural NetworksHardnessIndentation hardnessElectronic Optical and Magnetic MaterialsAmorphous solidCondensed Matter::Materials ScienceCrystallographyIndentationCeramics and CompositesSurface layerDeformation (engineering)Composite material

description

Abstract The indentation size effect (ISE) has been studied in single crystals, polycrystals and amorphous solids using the Vickers microhardness test. The ISE is clearly present in single crystals but is absent in fine-grained polycrystals. A size-dependent hardness for amorphous solids is observed only in the sub-micrometre surface layer. The behaviour of the ISE in single crystals for micro- and nanoindentation is compared. Estimates of the surface hardness are made by the extrapolation of the experimental hardness–indentation depth curves. The extrapolated hardness in the surface region reaches values corresponding to the theoretical shear strength. The results confirm the multifarious nature of the ISE contributed by the surface effect, strain gradient work hardening and non-dislocation mechanisms of deformation.

https://doi.org/10.1016/j.actamat.2005.12.031