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http://dx.doi.org/10.5762/KAIS.2016.17.12.98

Correction of the hardness measurement for pile-up materials with a nano indentation machine  

Park, Moon Shik (Department of Mechanical Engineering, Hannam University)
Publication Information
Journal of the Korea Academia-Industrial cooperation Society / v.17, no.12, 2016 , pp. 98-106 More about this Journal
Abstract
Measurements of the elastic modulus and hardness using a nano indentation machine rely on the equation for the fitted contact area, which is valid for only sink-in materials. For most soft engineering materials that involve pile-up behavior rather than sink-in, the contact area equation underestimates the contact area and thus overestimates the elastic modulus and hardness. This study proposes a correction method to amend erroneous hardness measurements in pile-up situations. The method is a supplemental derivation to the original hardness measurement with the known value of the elastic modulus. The method was examined for soft engineering metals, Al 6061 T6 and C 12200, via tensile tests, nano indentation tests, impression observations, and finite element analysis. The proposed technique shows reasonable agreement with the analytical results accounting for strain gradient plasticity from a previous study.
Keywords
Berkovich indenter; Indentation size effect; Hardness measurement; Nano indentation; Pile-up phenomenon;
Citations & Related Records
Times Cited By KSCI : 5  (Citation Analysis)
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