Fracture Prediction Based on Evaluation of Initial Porosity Induced By Direct Energy Deposition

Abstract

Additive manufacturing (AM) of metals proved to be beneficial in many industrial and non-industrial areas due to its low material waste and fast stacking speed to fabricate high performance products. The present contribution addresses several known challenges including mechanical behaviour and porosity analysis on directed energy deposition (DED) manufactured stainless steel 316L components. The experimental methodology consisting of metal deposition procedure, hardness testing and fractographic observations on manufactured mini-tensile test samples is described. A ductile fracture material model based on the Rousselier damage criterion is utilized within a FE framework for evaluation of material global response and determination of initial porosity value representing the structure’s nucleating void population. Alternatively, the initial pore sizes are characterized using the generalized mixture rule (GMR) analysis and the validity of the approach is examined against the experimental results.