Article
Mechanics
Thomas Beerli, Vincent Grolleau, Dirk Mohr, Christian C. Roth
Summary: A new axisymmetric V-bending technique is proposed to identify the strain to fracture for plane strain tension for the weakest in-plane direction of sheet metal. Experimental results show that the method is robust and exhibits low sensitivity to geometric imperfections. Experiments on different materials validate the proposed technique through comparison with conventional methods.
INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES
(2022)
Article
Materials Science, Multidisciplinary
Xifeng Li, Wenbing Yang, Dongkai Xu, Ke Ju, Jun Chen
Summary: A new ductile fracture criterion is proposed based on void nucleation, growth, and coalescence, with stress triaxiality as the main influence factor. It shows better prediction accuracy and stability compared to other criteria, especially under high stress triaxiality conditions.
INTERNATIONAL JOURNAL OF DAMAGE MECHANICS
(2021)
Article
Mechanics
Xue Yang, Yazhou Guo, Yulong Li
Summary: In this paper, the effects of three stress invariants on material failure are studied, and a new ductile failure criterion that considers the influence of stress triaxiality and normalized third invariant of deviatoric stress tensor is proposed. The new criterion is calibrated with test results on different materials, and it demonstrates high accuracy in predicting failure loci. Comparisons with other criteria show that the proposed criterion has a broader application range for the studied materials.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Mechanics
Suranjit Kumar, M. K. Samal, P. K. Singh, J. Chattopadhyay
Summary: This paper aims to predict the ductile fracture in low alloy steel specimens with pure tension, pure shear and combined shear-tension type loading using modified Madou-Leblond (MML) porous plasticity model proposed by the present authors. The MML model includes the effect of localised mode of plastic deformation in a narrow band and damage parameter contributions due to void growth process and shear localisation process. The numerical simulations results obtained using MML model has been compared with those of experiments, showing good performance in predicting material softening behaviour and critical fracture location.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Materials Science, Multidisciplinary
Nathan Spulak, Jeremy Seidt, Amos Gilat
Summary: The ductile fracture behavior of 2024 aluminum under unequal in-plane biaxial tension and out-of-plane compression is studied using a novel experimental design and numerical simulations. Fracture is observed directly during loading in unbacked specimens and using interrupted testing and acoustic emissions in tests with a backing plate. The plasticity model used in the simulations is validated by matching the simulated response with experimental data, and the equivalent plastic fracture strain is determined for various stress states.
MECHANICS OF MATERIALS
(2023)
Article
Chemistry, Physical
Felix Rickhey, Seokmoo Hong
Summary: This study investigates the crucial parameter of stress triaxiality (eta) in ductile damage prediction, particularly for anisotropic materials. It presents an alternative method to obtain eta directly from strains, and validates different yield criteria for predicting triaxiality. The findings have significant implications for damage prediction and design in materials.
Article
Engineering, Industrial
Takashi Matsuno, Kouta Nakagiri, Tomoko Matsuda, Toshiyuki Tanaka, Takashi Yasutomi, Hiroto Shoji, Mitsuru Ohata
Summary: This study identified the strain/stress range during shearing of conventional and improved AISI-D2 tool steels, and proposed ductile fracture design curves for evaluation. The results indicated the superiority of the improved AISI-D2 steel material, highlighting a drastically large fracture strain compared to high-pressure tensile tests.
JOURNAL OF MATERIALS PROCESSING TECHNOLOGY
(2022)
Article
Mechanics
Yagmur Gocmen, Can Erdogan, Tuncay Yalcinkaya
Summary: In this study, the ballistic response of Armox 500T armor steel is numerically investigated using finite element analysis and two different damage models. The results show that the modified Mohr-Coulomb (MMC) model outperforms the Johnson-Cook (JC) model in predicting failure modes, while both models perform well in anticipating residual velocity. The study also explores the effects of projectile nose shape, target plate thickness, and impact angle, and discusses the importance of incorporating the Lode parameter in the models for accurate predictions.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Engineering, Industrial
Takashi Matsuno, Kouta Nakagiri, Tomoko Matsuda, Toshiyuki Tanaka, Takashi Yasutomi, Hiroto Shoji, Mitsuru Ohata
Summary: The deformation and fracture of tools during the shearing process of ultra-high-strength steel is a serious problem. This study used finite element simulations to evaluate improved tool edge designs and identified the strain/stress range for which no fracture occurs. The effectiveness of the proposed method was confirmed by demonstrating the superiority of the improved AISI-D2 steel material.
JOURNAL OF MATERIALS PROCESSING TECHNOLOGY
(2022)
Article
Mechanics
Luca Quagliato, Joonhee Lee, Dosuck Han, Hyungyil Lee, Naksoo Kim
Summary: In this study, a function correlating failure strain and stress triaxiality was developed through combined experimental and finite element analysis, providing a viable failure criterion for complex components made of short fiber-reinforced polymers during the design stage where direct testing is not possible.
ENGINEERING FRACTURE MECHANICS
(2021)
Article
Construction & Building Technology
Qun He, Michael C. H. Yam, Zhiyang Xie, Xue-Mei Lin, Kwok-Fai Chung
Summary: In this study, it is shown that the classical J2 flow theory is inappropriate for describing the plastic behavior of structural steels under different stress states. A numerical framework is proposed to characterize the strain hardening and ductile fracture initiation considering the effect of stress states. The validity of the proposed model is verified through single element tests and existing test results.
STEEL AND COMPOSITE STRUCTURES
(2022)
Article
Engineering, Civil
A. Deifalla
Summary: Punching shear failure of reinforced concrete slabs is a sudden and catastrophic event. Developing a physically sound punching shear mechanical model can help understand and predict the behavior of slabs under in-plane tensile forces and punching shear.
ENGINEERING STRUCTURES
(2021)
Article
Engineering, Mechanical
Jun He, Sidong Feng, George Vasdravellis, Haohui Xin, Jose A. F. O. Correia, Filippo Berto
Summary: This study investigates the structural behavior of a demountable 'lockbolt' shear connector (LB-DSC) under combined tension and shear loading through numerical simulations and experimental tests. Design equations are proposed to expand the application of the LB-DSCs in sustainable steel-concrete composite construction.
ENGINEERING FAILURE ANALYSIS
(2022)
Article
Engineering, Multidisciplinary
Sina Abrari Vajari, Matthias Neuner, Prajwal Kammardi Arunachala, Andy Ziccarelli, Gregory Deierlein, Christian Linder
Summary: Phase field models for ductile fracture have been widely studied, but most existing methods only consider the effects of plastic deformation and neglect the multi-axial stress states in practical designs. In this work, a thermodynamically consistent phase field method coupled with finite strain plasticity is proposed to address this issue. The Stress-Weighted Ductile Fracture Model (SWDFM) is utilized to capture the coupling between plasticity and stress states. The excellent performance of the SWDFM in predicting ductile crack initiation motivates its incorporation into the phase field approach for predicting crack initiation and propagation.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2022)
Article
Materials Science, Multidisciplinary
Miguel Ruiz de Sotto, Veronique Doquet, Patrice Longere, Jessica Papasidero
Summary: In this study, an extensive experimental campaign and numerical simulations were conducted to investigate the ductile fracture behavior of Ti-6Al-4V titanium alloy. The results showed that ductility of the material exhibited anisotropic characteristics depending on the stress state and strain rate, with different behavior observed in tension and compression. The fracture strain was found to decrease with increasing absolute value of the triaxiality, reaching a maximum close to zero, while no clear correlation with the Lode parameter was identified.
INTERNATIONAL JOURNAL OF DAMAGE MECHANICS
(2022)