The third Sandia Fracture Challenge: deterministic and probabilistic modeling of ductile fracture of additively-manufactured material
- 136 Downloads
Within the scope of the third Sandia Fracture Challenge the plasticity and ductile fracture behavior of an additively manufactured 316L stainless steel tensile specimen containing through holes and internal cavities is predicted in a blind round robin format. Only a limited number of experimental results, including flat dogbone-shaped and double-notch tension specimens, as well as EBSD maps of the Challenge geometry are provided by Sandia National Laboratory. A non-associated Hill’48 plasticity model with Swift-Voce strain hardening and Johnson–Cook strain rate hardening is used to accurately describe the large deformation response of the material. A special case of the recently developed Hosford–Coulomb model is used to predict fracture initiation and propagation by crack re-initiation. Very good qualitative and quantitative agreement of the blind prediction with the experimental results is obtained for both global force-displacement responses as well as the local surface strain evolution throughout the test. In a post challenge follow-up study, the role of the plasticity model is evaluated, focusing on the effect of the anisotropy and the strain-rate on the material response. Aside from considering the deterministic model, the statistical material properties of the additively manufactured structure are analyzed by defining a heterogeneous random media model. Probabilistic material properties for both plasticity and fracture are assigned to each element of the Challenge specimen. As an alternative, the role of intrinsic porosities is analyzed by randomly deleting 1% of the pristine geometry. The results of both approaches show that the presence of homogeneities follows a more realistic description of the material behavior, especially in the crack propagation regime post maximum force and when looking at local strains.
KeywordsSandia fracture challenge Additive manufacturing Ductile fracture Hosford–Coulomb Probabilistic plasticity and fracture
The authors would like to thank Prof. Dirk Mohr (ETH) and Prof. Tomasz Wierzbicki (MIT) for fruitful discussions. The MIT fracture consortium is thanked for partial financial support.
- Bhavar V, Kattire P, Patil V, Khot S, Gujar K, Singh R (2014) A review on powder bed fusion technology of metal additive manufacturing. In: 4th International conference and exhibition on additive manufacturing technologies-AM-2014, September, pp 1–2Google Scholar
- Boyce BL, Kramer SLB, Bosiljevac TR, Corona E, Moore JA, Elkhodary K, Simha CHM, Williams BW, Cerrone AR, Nonn A, Hochhalter JD (2016) The second Sandia Fracture Challenge: predictions of ductile failure under quasi-static and moderate-rate dynamic loading. Int J Fract 198(1–2):5–100CrossRefGoogle Scholar
- Brackett D, Ashcroft I, Hague R (2011) August. Topology optimization for additive manufacturing. In: Proceedings of the solid freeform fabrication symposium, Austin, TX, Vol. 1, pp. 348–362Google Scholar
- Foust M, Thomsen D, Stickles R, Cooper C, Dodds W (2012) Development of the GE aviation low emissions TAPS combustor for next generation aircraft engines. In: 50th AIAA aerospace sciences meeting including the new horizons forum and aerospace expositionGoogle Scholar
- Kramer SLB, Boyce BL, Jones A, Mostafa A, Ravaji B, Tancogne-Dejean T, Roth CC, Gorji MB, Pack K, Foster JT, Behzadinasab M, Sobotka JC, McFarland JM, Stein J, Spear AD, Newell P, Czabaj MW, Williams BW, Simha CM, Gesing M, Gilkey LN, Jones CA, Dingreville R, Sanborn SE, Bignell JL, Cerrone A, Keim V, Nonn A, Cooreman S, Thibaux P, Ames N, O’Connor DT, Parno MD, Davis B, Tucker J, Coudrillier B, Karlson KN, Ostien JT, Foulk III JW, Hammetter CI, Grange S, Emery JM, Brown JA, Bishop JE, Johnson KL, Ford KR, Brinckmann S, Neilsen MK, Jackiewicz J, Ravi-Chandar K, Ivanoff TA, Salzbrenner BC (2019) The third Sandia Fracture Challenge: predictions of ductile fracture in additively manufactured metal. Int J FractGoogle Scholar
- Voce E (1948) The relationship between stress and strain for homogeneous deformation. J Inst Metals 74:537–562Google Scholar
- Wang YM, Voisin T, McKeown JT, Ye J, Calta NP, Li Z, Zhu T (2017) Additively manufactured hierarchical stainless steels with high strength and ductility. Nat Mater 17:63Google Scholar