The Development of the Cavitated Volume Fraction as a Creep Damage Indicator for Creep Remnant Life Prediction

This paper highlights the advantages of using the cavitated volume fraction (fv) as a superior creep damage indicator compared to traditional two dimensional (2D) based parameters. With the emergence of three dimensional (3D) experimental techniques like X-ray tomography, in-situ volumetric observations have become feasible, enabling a more accurate assessment of creep damage. The cavitated volume fraction offers a comprehensive evaluation of cavity distribution, overcoming the limitations of missing information and the impact of cavity coalescence on 2D-based assessments. We present the procedure for deriving the cavitated volume fraction using the cavity size distribution function and the cavity growth pattern equation. Additionally, we discuss the potential application of the cavitated volume fraction for rupture time prediction using early-stage creep data. Overall, this paper emphasizes the importance of adopting 3D-based parameters, specifically the cavitated volume fraction, for improved creep damage assessment and lifetime prediction.