Wednesday  |  Phipps  |  02:30 PM–02:50 PM

#13670, Fracture of Additively Manufactured Metals: Effect of Stress State and Pores on Fracture in low- and High-ductility Metals

The effect of internal pores and stress state on the fracture behavior of stainless steel 316, a relatively high ductility metal, and Ti-6Al-4V, a relatively low ductility metal, manufactured using laser powder bed fusion (L-PBF) additive manufacturing (AM) was investigated. Single internal penny-shaped pores, with varying diameters, were intentionally fabricated inside cylinders during the L-PBF AM process. Uniaxial tension and higher stress triaxiality notched tension specimens were machined from these cylinders, and samples were tested under tensile loading to simultaneously probe the effect of pore size and stress triaxiality (proportional to negative pressure) on the measured ductility of each of the metal alloys. Finite element analysis simulations of all tests were performed to identify the evolution of stress state and strain accumulation within samples up to fracture. This presentation will describe the fracture models used to capture these data as well as the impact of defects on fracture on these two disparate alloys.

Allison Beese   Pennsylvania State University