Multiscale nanoindentation modelling of newborn piglet cortical bone.

Abstract

This study presents an integrated experimental-numerical framework for the multiscale mechanical characterization of dehydrated newborn piglet cortical bone. A self-calibrated nanoindentation methodology, coupled with inverse finite element identification based on the Johnson-Cook constitutive model, is introduced to quantify both surface and bulk mechanical properties. Particular attention is given to indentation size effects and preliminary sex-related trends in mechanical response. The proposed framework enables robust estimation of elastoplastic parameters and highlights the presence of a mechanically modified surface layer whose properties differ from those of the bone core, potentially due to local preparation effects, dehydration, or microstructural heterogeneity. The proposed methodology provides new insight into the structure-property relationships governing neonatal cortical bone mechanics and may support future predictive models for fracture assessment and biomaterial design.