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The presence of inclusions is a known source of crack initiation and component failure in cast materials. In this work, the role of inclusions is investigated via a combined program of high‐temperature low‐cycle fatigue testing and computational modelling of a tempered martensitic steel, MarBN. Microstructural analysis has shown that manufacturing‐induced oxide inclusions are a key source of fatigue crack initiation. A fully coupled, critical plane life prediction and damage model is implemented in a unified cyclic viscoplastic user‐material subroutine and applied to predict damage and micro‐crack initiation for inclusions. It is deduced that more careful control of the development of inclusions in the manufacturing process will provide enhanced material and component performance for highly flexible and ultrasupercritical plant conditions. [ABSTRACT FROM AUTHOR]

This paper investigates the effects of pre‐corrosion on the tensile behavior of aluminum alloy 7050‐T7651. A combined experimental approach involving digital image correlation, scanning electron microscopy, and tensile testing is presented for quantitative and qualitative analysis. A tensile damage model is presented for plasticity‐induced, post‐corrosion mechanical damage for interpretation and identification of damage and cracking thresholds. Although multiple corrosion‐induced cracks evolve simultaneously in diffuse regions, propagation and coalescence of the main cracks, originating from key damage regions, dominate the failure process. A combined corrosion and mechanical damage model was used to successfully predict the effects of pre‐corrosion on the tensile stress‐strain response. Highlights: Full‐field macro‐microscale characterization of tensile damage and cracking for aluminum alloy using digital image correlation, scanning electron microscopy, and tensile testing.Corrosion‐plasticity damage mechanics model for effects of pre‐corrosion.Identification of post‐corrosion evolution of damage, strain, micro‐cracking initiation, and coalescence, as well as crack orientation and propagation.Multiple diffuse cracks evolve simultaneously, but propagation‐coalescence of main cracks in key damage regions dominates failure process. [ABSTRACT FROM AUTHOR]