Investigation by 3D nano-holotomography of the interfacial strength of oxide inclusions in iron

Oxide inclusions are an unavoidable side products of steelmaking having detrimental effects on the fatigue and fracture properties of steel, hence their very different local mechanical properties than of the steel matrix in which they are embedded. In the current proposal, we are aiming to implement holographic X-ray nanotomography coupled with step-wise tensile loading in order to enable the observation of void formation as a result of the inclusion detachment from the matrix under external load. The resulting tomographic data will be complemented with finite-element modeling in order to estimate the lower bound of the inclusion - matrix bond strength. The proposed experiments will contribute to the fundamental understanding of external-load driven debonding of oxide inclusions, being one of the primary cause of fatigue failure and will provide valuable information for the ceramics scientific community too.