TY - JOUR A1 - Boyce, Brad L. A1 - Kramer, Sharlotte L. B. A1 - Bosiljevac, T. R. A1 - Corona, Edmundo A1 - Moore, J. A. A1 - Elkhodary, Khalil A1 - Simha, C. Hari Manoj A1 - Williams, Bruce W. A1 - Cerrone, Albert R. A1 - Nonn, Aida A1 - Hochhalter, Jacob D. A1 - Bomarito, Geoffrey F. A1 - Warner, James E. A1 - Carter, Bruce J. A1 - Warner, Derek H. A1 - Ingraffea, Anthony R. A1 - Zhang, T. A1 - Fang, X. A1 - Lua, Jim A1 - Chiaruttini, Vincent A1 - Maziere, Matthieu A1 - Feld-Payet, Sylvia A1 - Yastrebov, Vladislav A. A1 - Besson, Jacques A1 - Chaboche, Jean Louis A1 - Lian, J. A1 - Di, Y. A1 - Wu, Bei A1 - Novokshanov, Denis A1 - Vajragupta, Napat A1 - Kucharczyk, Pawel A1 - Brinnel, Viktoria A1 - Doebereiner, Benedikt A1 - Muenstermann, Sebastian A1 - Neilsen, Michael K. A1 - Dion, Kristin A1 - Karlson, Kyle N. A1 - Foulk, James Wesley A1 - Brown, Arthur A. A1 - Veilleux, Michael G. A1 - Bignell, John L. A1 - Sanborn, Scott E. A1 - Jones, Chris A. A1 - Mattie, Patrick D. A1 - Pack, Keunhwan A1 - Wierzbicki, Tomasz A1 - Chi, Sheng-Wei A1 - Lin, S.-P. A1 - Mahdavi, Ashkan A1 - Predan, Jozef A1 - Zadravec, Janko A1 - Gross, Andrew J. A1 - Ravi-Chandar, KRISHNASWAMY A1 - Xue, Liang T1 - The second Sandia Fracture Challenge: predictions of ductile failure under quasi-static and moderate-rate dynamic loading JF - International journal of fracture N2 - Ductile failure of structural metals is relevant to a wide range of engineering scenarios. Computational methods are employed to anticipate the critical conditions of failure, yet they sometimes provide inaccurate and misleading predictions. Challenge scenarios, such as the one presented in the current work, provide an opportunity to assess the blind, quantitative predictive ability of simulation methods against a previously unseen failure problem. Rather than evaluate the predictions of a single simulation approach, the Sandia Fracture Challenge relies on numerous volunteer teams with expertise in computational mechanics to apply a broad range of computational methods, numerical algorithms, and constitutive models to the challenge. This exercise is intended to evaluate the state of health of technologies available for failure prediction. In the first Sandia Fracture Challenge, a wide range of issues were raised in ductile failure modeling, including a lack of consistency in failure models, the importance of shear calibration data, and difficulties in quantifying the uncertainty of prediction [see Boyce et al. (Int J Fract 186:5-68, 2014) for details of these observations]. This second Sandia Fracture Challenge investigated the ductile rupture of a Ti-6Al-4V sheet under both quasi-static and modest-rate dynamic loading (failure in 0.1 s). Like the previous challenge, the sheet had an unusual arrangement of notches and holes that added geometric complexity and fostered a competition between tensile- and shear-dominated failure modes. The teams were asked to predict the fracture path and quantitative far-field failure metrics such as the peak force and displacement to cause crack initiation. Fourteen teams contributed blind predictions, and the experimental outcomes were quantified in three independent test labs. Additional shortcomings were revealed in this second challenge such as inconsistency in the application of appropriate boundary conditions, need for a thermomechanical treatment of the heat generation in the dynamic loading condition, and further difficulties in model calibration based on limited real-world engineering data. As with the prior challenge, this work not only documents the 'state-of-the-art' in computational failure prediction of ductile tearing scenarios, but also provides a detailed dataset for non-blind assessment of alternative methods. KW - Alloy KW - BEHAVIOR KW - CRACK-PROPAGATION KW - DAMAGE KW - Deformation KW - Fracture KW - HIGH-STRAIN-RATE KW - KERNEL PARTICLE METHODS KW - Metal KW - MODEL KW - Modeling KW - Plasticity KW - POLYCRYSTALLINE AL 6061-T6 KW - PREDICTION KW - ROOM-TEMPERATURE KW - Rupture KW - simulation KW - STRENGTH STEEL SHEETS KW - Tearing Y1 - 2016 U6 - https://doi.org/10.1007/s10704-016-0089-7 IS - 198, 1-2 SP - 5 EP - 100 PB - Springer ER - TY - CHAP A1 - Eixelberger, Thomas A1 - Wittenberg, Thomas A1 - Perret, Jerome A1 - Katzky, Uwe A1 - Simon, Martina A1 - Schmitt-Rüth, Stephanie A1 - Hofer, Mathias A1 - Sorge, M. A1 - Jacob, R. A1 - Engel, Felix B. A1 - Gostian, A. A1 - Palm, Christoph A1 - Franz, Daniela T1 - A haptic model for virtual petrosal bone milling T2 - 17. Jahrestagung der Deutschen Gesellschaft für Computer- und Roboterassistierte Chirurgie (CURAC2018), Tagungsband, 2018, Leipzig, 13.-15. September N2 - Virtual training of bone milling requires realtime and realistic haptics of the interaction between the ”virtual mill” and a ”virtual bone”. We propose an exponential abrasion model between a virtual one and the mill bit and combine it with a coarse representation of the virtual bone and the mill shaft for collision detection using the Bullet Physics Engine. We compare our exponential abrasion model to a widely used linear abrasion model and evaluate it quantitatively and qualitatively. The evaluation results show, that we can provide virtual milling in real-time, with an abrasion behavior similar to that proposed in the literature and with a realistic feeling of five different surgeons. KW - Osteosynthese KW - Simulation KW - Lernprogramm Y1 - 2018 UR - https://www.curac.org/images/advportfoliopro/images/CURAC2018/CURAC 2018 Tagungsband.pdf VL - 17 SP - 214 EP - 219 ER -