Notched fatigue of additive manufactured metals under axial and multiaxial loadings, part II: Data correlations and life estimations


Fatigue performance of additive manufactured (AM) metals is highly sensitive to the existence of defects. This becomes more challenging when mechanically induced stress concentrations due to notches or complexities in the geometries are also present. Multiaxial stress states are additional important consideration in designing parts for critical load carrying applications. In this work, notched uniaxial and multiaxial fatigue and cracking behavior of two commonly used AM metals (Ti-6Al-4V and 17–4 PH stainless steel) with different post fabrication heat treatments and surface roughness conditions were studied. In part I of these two-part paper series, AM notch test results were compared to AM unnotched as well as to the notched and unnotched wrought counterparts. In this second part, both crack initiation (i.e., critical plane-based method) and crack growth (i.e., fracture mechanics-based method) approaches are used for uniaxial and multiaxial data correlations and life estimations. Both approaches are shown to result in satisfactory estimations of the experimental results.

Publication Title

International Journal of Fatigue