Contact size-independent method for estimation of creep properties with spherical indentation

Abstract Steady-state creep constitutes a major portion in the creep (strain vs. time) curve and is usually analyzed in characterizing creep behavior. In this numerical study, adopting a power-law creep material model, we propose a contact size-independent method for deriving creep properties from short-time spherical indentation test. Using finite element (FE) method with a wide range of creep properties, we investigate the characteristics of steady-state creep, while a fixed observation point beneath the indenter is employed to measure the material response to the indentation. We then establish functions that map indentation load–depth data to stress–strain rate data which provides creep properties without measuring the contact area. The proposed method provides the creep coefficients and the creep exponents with great accuracy from the indentation load–depth curves.