Yield behaviour beneath hardness indentations in ductile metals, measured by three-dimensional computed X-ray tomography and digital volume correlation

Plastic deformation in the vicinity of hardness indentations in two ductile metals, an aluminium–silicon carbide composite (Al–SiC) and a cast magnesium alloy (WE43), was characterized. Using in situ and ex situ X-ray computed tomography with digital volume correlation, the three-dimensional full-field displacements beneath the indentations were measured; these show strong agreement with simulated predictions using finite element models. It is demonstrated that plastic material properties, i.e. yield stress and hardening exponent, may be extracted via analysis of the deformation field.