Fatigue life prediction of FV520B with internal inclusions

• The experiment for FV520B fatigue property is helpful in fatigue life prediction.
• The experimental data made a contribution to the establishment of the model.
• A specific fatigue life prediction model for FV520B is established.
• A contribution to the study of remanufacturing.

Fatigue life prediction of high strength material such as FV520B is a primary concern in remanufacturing engineering theory and research development, is an important research topic in the field. However, few studies about FV520B fatigue property exist in literature. This paper discusses a fatigue experiment for life prediction model conducted in the UFTS (Ultrasonic Fatigue Test System) at 20 kHz. Based on the obtained fatigue failures, test data, and observed GBF (Granular Bright Facet) and “fish-eye”, the analysis results prove that inclusions can be a principal cause of the fatigue failure in giga-cycle stage. After employing a fitting algorithm and determining the model unknown parameters, based on the fatigue data including life and inclusion size, an FV520B empirical life prediction model is identified. Model validation is performed through the analysis of errors between the model and experimental data, which are shown within an accepted tolerance for its engineering applicability. The model applicable for the FV520B life prediction and is an influences to the life study of high strength materials. It is highly beneficial to the research development in remanufacturing engineering as well.