International Journal of Fracture最新文献

{"title":"The tearing energy threshold of crack growth in rubber exposed to ozone: an experimental–numerical approach","authors":"Ondřej Peter,&nbsp;Martin Stěnička,&nbsp;Gert Heinrich,&nbsp;Christopher G. Robertson,&nbsp;Jakub Pawlas,&nbsp;Radek Stoček,&nbsp;Jan Ondrík","doi":"10.1007/s10704-024-00799-y","DOIUrl":"10.1007/s10704-024-00799-y","url":null,"abstract":"<div><p>The global rubber industry is seeking alternatives to the widely-used antiozonant, <i>N</i>-(1,3-dimethylbutyl)-<i>N</i>′-phenyl-<i>p</i>-phenylenediamine (6PPD), due to its environmental toxicity concerns when used in automobile tires. These substantial research and development efforts on new antiozonants for rubber are hindered by a general inability to characterize the fundamental physical parameter of ozone-induced tearing energy threshold for crack growth, which underlies the practical ozone resistance of rubber products. Therefore, this paper presents, for the first time, a novel experimental–numerical combined approach to determine the tearing energy threshold in rubber exposed to ozone, which is a key criterion for assessing the resistance of rubber to ozone crack growth. The approach is based on in-situ optical analysis of ozone crack growth on the rubber surface and the determination of the crack growth rate when the rubber is stretched. Subsequently, the growth rates form the basis for calculating the energy release rates at the crack tips using the finite element method in Ansys software. By comparing the calculated energy release rates and experimentally measured crack growth rates, the energy release rate interval corresponding to the threshold tearing energy is determined. Based on this approach, the tearing energy threshold for carbon black reinforced natural rubber exposed to ozone was found to be a maximum of 2.12 J/m². This value is 96% lower than the threshold for the non-ozone-exposed specimens. In conclusion, this novel methodology was able to determine the ozone threshold tearing energy and represents a powerful, unique tool for an efficient future development of environmentally friendly antiozonants.</p></div>","PeriodicalId":590,"journal":{"name":"International Journal of Fracture","volume":"248 1-3","pages":"49 - 66"},"PeriodicalIF":2.2,"publicationDate":"2024-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10704-024-00799-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141347528","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrating atomistics and experiments in gaining deeper insights into fatigue crack propagation in silver","authors":"Yinan Xie,&nbsp;Xiaoli Hao,&nbsp;Zumin Wang,&nbsp;Yuan Huang","doi":"10.1007/s10704-024-00796-1","DOIUrl":"10.1007/s10704-024-00796-1","url":null,"abstract":"<div><p>This research utilizes both single crystal and polycrystalline models to probe the fatigue crack propagation mechanism in pure silver via molecular dynamics (MD) simulations. A comprehensive validation approach at both micro and macro scales, incorporating transmission electron microscopy (TEM), electron backscatter diffraction (EBSD), and compact tension (CT) specimen fatigue testing, is developed to verify the reliability of simulation models and results. Simulation findings indicate that the initial crack orientation significantly influences crack propagation. As the crack advances within the crystal, two primary crack propagation mechanisms are discerned: (1) nano-voids appear at the crack tip, and the crack propagates by continuously aggregating with the nano-voids ahead; (2) the formation of Stair-rod dislocations and V-shape stacking faults due to dislocation reactions and slip band movements impedes crack propagation, accompanied by the dislocation reaction of Shockley partial dislocations (<span>(tfrac{1}{6})</span> &lt;112&gt;) generating Hirth dislocations (<span>(tfrac{1}{6})</span> &lt;110&gt;). The dislocation reaction is verified through the dislocation analysis of the crack tip area of the CT specimen after fatigue experiment by using TEM. In addition, the results of this study show that the angle between the direction of crack propagation and the grain boundary affects the fatigue crack propagation, e.g. when the angle is less than 60°, the crack rapidly propagates along the grain boundary. The orientation distribution function (ODF) results of EBSD can verify that the polycrystalline model containing 30 grains is a reliable model for the MD simulation of behavior of the crack tip of CT specimen. Lastly, the Paris law constants for pure silver are determined as <i>m</i> = 3.72 and lg <i>C</i> = − 10.77, providing a reference for the fatigue analysis and life prediction of silver components or silver soldering pots in engineering applications.</p></div>","PeriodicalId":590,"journal":{"name":"International Journal of Fracture","volume":"247 3","pages":"383 - 411"},"PeriodicalIF":2.2,"publicationDate":"2024-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141350746","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced solid element model with embedded strong discontinuity for representation of mesoscale quasi-brittle failure","authors":"Matej Šodan,&nbsp;Andjelka Stanić,&nbsp;Mijo Nikolić","doi":"10.1007/s10704-024-00797-0","DOIUrl":"10.1007/s10704-024-00797-0","url":null,"abstract":"<div><p>This article presents a novel two-dimensional quadrilateral solid finite element model, enhanced by incompatible modes and embedded strong discontinuity for simulation of localized failure in quasi-brittle heterogeneous multi-phase materials. The focus of interest lies in the development of discontinuities and cracks induced by both tensile and compressive loads, considering mesoscale material constituents and very complex meshes. Multiple cracks are initiated within elements using local Gauss-point criteria for crack initiation. Rankine and Maximum shear stress criteria control the crack initiation, location, and orientation depending solely on the stress state within the finite element. The model identifies distinct clusters of cracked elements and merges them into continuous cracks. A tracking algorithm ensures crack continuity, eliminating spurious cracks ahead of the crack tip to prevent crack arrest and stress locking. This approach ensures the formation of various types of cracks within the constituents of composite materials and their spontaneous coalescence forming the final failure mechanisms. The constitutive model for the crack representation is the damage softening model, which accounts for opening and sliding behavior. The efficacy of the proposed model is demonstrated through numerical simulations of heterogeneous 3-phase and 4-phase composites subjected to both tensile and compressive load cases.</p></div>","PeriodicalId":590,"journal":{"name":"International Journal of Fracture","volume":"248 1-3","pages":"1 - 25"},"PeriodicalIF":2.2,"publicationDate":"2024-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141384025","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microstructure based fatigue life prediction of polycrystalline materials using SFEM and CDM","authors":"Deepak Sharma,&nbsp;I. V. Singh,&nbsp;Jalaj Kumar,&nbsp;Shahnawaz Ahmed","doi":"10.1007/s10704-024-00795-2","DOIUrl":"10.1007/s10704-024-00795-2","url":null,"abstract":"<div><p>Accurate fatigue life prediction of polycrystalline materials is crucial for many engineering applications. In polycrystalline materials, a significant portion of life is spent in the crack nucleation phase at the microstructural scale. Hence, the total fatigue life shows high sensitivity to the local microstructure. To predict fatigue life accurately, the microstructure models of polycrystalline material i.e., titanium alloy are virtually generated with the help of the Voronoi tessellation technique. These models incorporate critical microstructural features such as grain size, grain shape, and the volume fraction of different phases within the material. To efficiently predict microstructure sensitive fatigue life, the smooth finite element method (SFEM) is coupled with continuum damage mechanics (CDM). The SFEM provides flexibility in the meshing of complex microstructure geometries as it alleviates the need to use only triangular and quadrilateral elements. Moreover, there is no need of isoparametric mapping and explicit form of shape function derivatives in SFEM, hence it requires less computation time. To obtain the fatigue life (in number of cycles), jump in cycles algorithm is implemented using SFEM-CDM. The numerical results of fatigue life data obtained from simulations are compared with experimental data, which reveals the validity of the present approach. This approach is useful to find out the scatter in fatigue life data of polycrystalline materials along with the source of scatter.</p></div>","PeriodicalId":590,"journal":{"name":"International Journal of Fracture","volume":"247 2","pages":"265 - 284"},"PeriodicalIF":2.2,"publicationDate":"2024-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141171582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effect of crack orientation on the mode I fracture resistance of pinewood","authors":"Marek Romanowicz,&nbsp;Maciej Grygorczuk","doi":"10.1007/s10704-024-00798-z","DOIUrl":"10.1007/s10704-024-00798-z","url":null,"abstract":"<div><p>The fracture resistance of pinewood under mode I loading is investigated experimentally for different crack plane orientations and the crack propagation direction parallel to longitudinal cells. Experiments are conducted on double cantilever beams using a digital image correlation system to evaluate the crack tip opening displacement. The compliance based beam method is used to determine the energy release rate at various crack lengths. The decomposition of crack propagation into the pre-peak and post-peak propagations is proposed to find the fracture energy contributions from individual toughening mechanisms in pinewood. The cohesive strengths measured in the experiments are confirmed by comparison with the tensile strengths obtained from separate tests performed on pinewood. An analytical model for evaluating the fracture process zone is used to validate the experimental results. The difference between the fracture energy values in different crack propagation systems is explained by using X-ray microtomography images of the fracture surfaces.</p></div>","PeriodicalId":590,"journal":{"name":"International Journal of Fracture","volume":"248 1-3","pages":"27 - 48"},"PeriodicalIF":2.2,"publicationDate":"2024-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10704-024-00798-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141171579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessing the fracture toughness of Zircaloy-4 fuel rod cladding tubes: impact of delayed hydride cracking","authors":"Pierrick François,&nbsp;Tom Petit,&nbsp;Quentin Auzoux,&nbsp;David Le Boulch,&nbsp;Isabela Zarpellon Nascimento,&nbsp;Jacques Besson","doi":"10.1007/s10704-024-00781-8","DOIUrl":"10.1007/s10704-024-00781-8","url":null,"abstract":"<div><p>Delayed hydride cracking (DHC) is a hydrogen embrittlement phenomenon that may potentially occur in Zircaloy-4 fuel claddings during dry storage conditions. An experimental procedure has been developed to measure the toughness of this material in the presence of DHC by allowing crack propagation through the thickness of a fuel cladding. Notched C-ring specimens, charged with 100 wppm of hydrogen, were used and pre-cracked by brittle fracture of a hydrided zone at the notch root at room temperature. The length of the pre-crack was measured on the fracture surface or cross-sections. Additionally, a finite element model was developed to determine the stress intensity factor as a function of the crack length for a given loading. Two types of tests were conducted independently to determine the fracture toughness with and without DHC, <span>(K_{I_text {DHC}})</span> and <span>(K_{I_text {C}})</span>, respectively: (i) constant load tests at 150 <span>(^{circ })</span>C, 200 <span>(^{circ })</span>C, and 250 <span>(^{circ })</span>C; (ii) monotonic tests at 25 <span>(^{circ })</span>C, 200 <span>(^{circ })</span>C, and 250 <span>(^{circ })</span>C. The results indicate the following: (1) there is no temperature influence on the DHC toughness of Zircaloy-4 between 150 and 250 <span>(^{circ })</span>C (<span>(K_{I_text {DHC}} in left[ 7.2;9.2right] )</span> MPa<span>(sqrt{text {m}})</span>), (2) within this temperature range, the fracture toughness of Zircaloy-4 is halved by DHC (<span>(K_{I_text {C}} in left[ 16.9;19.7 right] )</span> MPa<span>(sqrt{text {m}})</span>), (3) the crack propagation rate decreases with decreasing temperature and (4) the time before crack propagation increases as the temperature and loading decrease.</p></div>","PeriodicalId":590,"journal":{"name":"International Journal of Fracture","volume":"247 1","pages":"51 - 72"},"PeriodicalIF":2.2,"publicationDate":"2024-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140964526","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Introduction to the special issue on failure mechanism in advanced materials and structures","authors":"Zengtao Chen,&nbsp;Minghao Zhao,&nbsp;Cunfa Gao,&nbsp;Efstathios Theotokoglou","doi":"10.1007/s10704-024-00793-4","DOIUrl":"10.1007/s10704-024-00793-4","url":null,"abstract":"","PeriodicalId":590,"journal":{"name":"International Journal of Fracture","volume":"246 2-3","pages":"101 - 102"},"PeriodicalIF":2.2,"publicationDate":"2024-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140963377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fatigue crack growth behavior of a nickel-based superalloy under turbine standard spectrum loads","authors":"Sharanagouda G. Malipatil,&nbsp;N. Nagarajappa,&nbsp;Ramesh Bojja,&nbsp;N. Jagannathan,&nbsp;Anuradha N. Majila,&nbsp;D. Chandru Fernando,&nbsp;M. Manjuprasad,&nbsp;C. M. Manjunatha","doi":"10.1007/s10704-024-00794-3","DOIUrl":"10.1007/s10704-024-00794-3","url":null,"abstract":"<div><p>In this investigation, the growth behavior of a crack in a nickel-based superalloy under a turbine standard load sequence was determined by experimental, analytical, and computational methods. In the first experimental approach, ASTM standard compact tension (CT) test specimens were fabricated and fatigue crack growth (FCG) tests were conducted in a universal test machine under cold-TURBISTAN, a turbine standard spectrum load sequence. In the second analytical method, after rain-flow cycle counting of the cold-TURBISTAN sequence, the crack growth was estimated for each counted cycle from the crack growth law. The accumulated crack extension for each block of loading was thus estimated to determine the FCG behavior. In the third computational approach, a CT specimen containing an initial crack was modeled and the FCG behavior was predicted under cold-TURBISTAN spectrum load sequence using FRANC3D. The FCG trend predicted by analytical and computational methods was almost similar to the observed experimental behavior. The predicted FCG life was conservative with a life ratio ranging from 0.9 to 0.95.</p></div>","PeriodicalId":590,"journal":{"name":"International Journal of Fracture","volume":"247 2","pages":"253 - 264"},"PeriodicalIF":2.2,"publicationDate":"2024-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140963629","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Boundary element method: cells with embedded discontinuity modeling the fracture process zone in 3D failure analysis","authors":"A. P. Chaves,&nbsp;R. G. Peixoto,&nbsp;R. P. Silva","doi":"10.1007/s10704-024-00785-4","DOIUrl":"10.1007/s10704-024-00785-4","url":null,"abstract":"<div><p>Damage and failure in quasi-brittle materials such as rocks, concrete, and ceramics, have a complex non-linear behavior due to their heterogeneous character and the development of a fracture process zone (FPZ), formed by micro-cracking around the tip of an induced or pre-existing flaw. A softening behavior is observed in the FPZ, and the linear elastic fracture mechanic (LEFM) cannot correctly reproduce the stress field ahead of the crack tip. The existence of the FPZ may be the intrinsic cause of the size effect. An appropriate modeling of this process zone is mandatory to reproduce accurately the failure propagation and consequently, the structural behavior. Different from most of the domain numerical techniques, the boundary element method (BEM) requires (besides the boundary division into elements) only the discretization of a small region where dissipative effects occur. Cells with embedded continuum strong discontinuity approach (CSDA), placed in the region where the crack is supposed to occur, are capable of capturing the transition of regimes in the failure zone. Numerical bifurcation analysis, based on the singularity of the localization tensor, is used to determine the end of the continuum regime. Weak and strong discontinuity regimes are associated with diffuse micro-cracks (strain discontinuity) and macro-crack (displacement discontinuity). A variable bandwidth model is used during the weak discontinuity regime to represent the advance of micro-cracks density and their coalescence. Continuum and discrete cohesive isotropic damage models are used to describe the softening behavior. Analysis of three-dimensional problems with single crack in standard and mixed fracture modes, using this transitional approach and the BEM cells is firstly presented in this work. Experimental reference results are used to attest the capability of the approach in reproducing the structural behavior during crack propagation. Some necessary advances required for its applications for general complex structural problems are pointed out.</p></div>","PeriodicalId":590,"journal":{"name":"International Journal of Fracture","volume":"247 1","pages":"107 - 132"},"PeriodicalIF":2.2,"publicationDate":"2024-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140968091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of a cracked harmonic substrate under a rigid punch","authors":"Hailiang Ma,&nbsp;Yueting Zhou,&nbsp;Xu Wang,&nbsp;Xing Li,&nbsp;Shenghu Ding","doi":"10.1007/s10704-024-00782-7","DOIUrl":"10.1007/s10704-024-00782-7","url":null,"abstract":"<div><p>The study of the mechanical action between a punch and a cracked substrate has some theoretical guidance for the material protection. So the coupling problem of a cracked semi-infinite harmonic substrate under the action of a rigid flat punch is studied. The mixed boundary value problem is transformed into the Riemann-Hilbert boundary value problem by applying the complex-variable method, and then converted into singular integral equation for a numerical solution. The stress intensity factors at the contact ends and crack tips and the Piola stresses of whole harmonic material can be expressed as complex functions. The results indicate that the stressed state of harmonic solid near the crack tip and contact ends have similar features as those in linear elastic solids. The crack causes an obvious impact on the stress distributions near the contact region. The study provides theoretical guidance for analyzing the damaged problems of some soft materials under small deformation.</p></div>","PeriodicalId":590,"journal":{"name":"International Journal of Fracture","volume":"247 1","pages":"73 - 86"},"PeriodicalIF":2.2,"publicationDate":"2024-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140933068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}