Literatura académica sobre el tema "Intragranular Fractures"
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Artículos de revistas sobre el tema "Intragranular Fractures"
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Liu, Guoping, Lianbo Zeng, Xiaojun Wang, Mehdi Ostadhassan, Zhenlin Wang, Zhe Mao y Qi Tie. "Natural fractures in deep tight gas sandstone reservoirs in the thrust belt of the southern Junggar Basin, northwestern China". Interpretation 8, n.º 4 (23 de julio de 2020): SP81—SP93. http://dx.doi.org/10.1190/int-2020-0051.1.
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The development of natural fractures is a significant characteristic of the Jurassic deep tight sandstone reservoirs in the thrust belt of the southern Junggar Basin, and these reservoirs have a great potential for natural gas resources. Based on the analyses of outcrops, cores, thin sections, and other laboratory data, natural fractures in these reservoirs are mainly tectonic ones, which appear in groups and vary in scale, dip angle, and density. We have classified fractures in thin sections into intragranular, grain boundary, and transgranular ones depending on their relationship with minerals grains. Almost 58% of the whole fracture population is opening-mode fractures, and calcite is the main filling mineral for the remaining ones. Fracture apertures vary based on their types, where transgranular fractures are the widest, followed by grain boundary and intragranular ones. Lithology, rock mechanical mechanics layers, and structures control the development of natural fractures. Fractures are more frequent in siltstone and fine sandstone. Sandstones with larger mineral grains are more likely to develop grain boundary and intragranular fractures. Intralayer fractures are the dominant ones, which intersect the rock mechanics interface at high angles or perpendicularly. The linear density of these fractures decreases when the thickness of the rock-mechanics layer increases. Furthermore, fractures have a higher degree of development in the hanging wall of the faults, with the degree decreasing when the distance from the fault plane increases. Additionally, the development degree of fractures in the damage zone is better than the adjacent rocks, and the width of damage zones is a function of the amount of fault displacement.
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Gong, Lei, Shuai Gao, Shu Ju Guo, Jian Guo Huang y Xian Xian Tao. "Characteristics and Sequences of Fractures in the Tight Conglomerate Reservoirs of Jiulongshan Structure". Advanced Materials Research 900 (febrero de 2014): 689–92. http://dx.doi.org/10.4028/www.scientific.net/amr.900.689.
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Fracture is an important controlling factor for the distribution of natural gas reservoirs in the tight conglomerate reservoirs in the Lower Jurassic Zhenzhuchong Formation at the north of Western Sichuan basin. Using the data of outcrops, cores, image logs and thin sections, combined with experimental analysis, we analyze the fracture origin types, distribution characteristics and formation sequences. There are three types of fractures, i.e. tectonic fractures, diagenetic fractures and original fractures in the tight conglomerate reservoirs. Among them, tectonic fractures are dominant, which can be classified into four sets, i.e. E-W, nearly S-W, NWW-SEE, NEE-SWW orientations. According to the statistics of areal density and fractal dimension, the average fracture areal density is 0.31cm/cm2, with the bulk in the range of 0.15-0.60cm/cm2. The fracture fractal dimensions are distributed at 0.95-1.70. There is a well positive correlation between fracture areal density and fractal dimension. Micro-fractures are important channels that connect matrix intergranular pores and intragranular dissolved pores, which improve the connectivity among pores. The tectonic fractures in the study area were formed in two periods, i.e. the end of Cretaceous and the end of Neogene.
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Nian, Tao, Yanze Li, Tao Hou, Chengqian Tan y Chao Liu. "Natural fractures at depth in the Lower Cretaceous Kuqa Depression tight sandstones: identification and characteristics". Geological Magazine 157, n.º 8 (13 de enero de 2020): 1299–315. http://dx.doi.org/10.1017/s0016756819001444.
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AbstractThe Kuqa Depression in the northern Tarim Basin, NW China, is characterized by fault-controlled anticlines where natural fractures may influence production. Natural fractures in the Lower Cretaceous tight sandstones in the depression have been studied using seismic profiles, borehole images, cores and thin-sections. Results show that thrust faults, two types of opening-mode macrofractures and two types of microfractures are present. Thrust faults were generated during Cenozoic N–S-directed tectonic shortening and have hydraulically linked Jurassic source rocks and Cretaceous sandstones. Opening-mode fractures can be subdivided on the basis of sizes, filling characteristics and distribution patterns. Type 1 macrofractures are barren or mainly calcite-lined. They have straight traces with widths (opening displacements) that are of the order of magnitude of 10 μm, suggesting that their primary role is that of migration channels. Type 2 macrofractures are calcite-filled opening-mode fractures. They have an elliptical or tabular shape with sharply tapering tips. Transgranular microfractures are lens-shaped and open or filled mostly by calcite; maximum widths range between 0.01 mm and 0.1 mm. Intragranular microfractures are the most common microfracture type. They are filled by calcite, feldspar or quartz. The macrofractures and transgranular microfractures have regular distributions, while most intragranular microfractures are irregularly distributed owing to their inherited origin. The results imply that natural fractures in the tight sandstones were formed as tectonic, diagenetic and natural hydraulic origins. In situ stress and cementation analyses suggest that Type 1 macrofractures and their genesis-related microfractures have controlled the present flow system of the tight sandstones.
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Campbell, Oliver, Tom Blenkinsop, Oscar Gilbert y Lisa Mol. "Surface and Subsurface Damage Caused by Bullet Impacts into Sandstone". Geosciences 11, n.º 9 (17 de septiembre de 2021): 395. http://dx.doi.org/10.3390/geosciences11090395.
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The shift of armed conflicts to more urbanised environments has increased the risk to cultural heritage sites. Small arms impacts are ubiquitous in these circumstances, yet the effects and mechanisms of damage caused are not well known. A sandstone target was shot under controlled conditions to investigate surface and subsurface damage. A 3D model of the damaged block, created by structure from motion photogrammetry, shows that internal fracturing was at least as extensive as the visible surface fractures. Backscatter electron imaging of the damaged surface shows a shift from intragranular fracturing and grain size reduction at <5 mm from the impact point to primarily circumgranular fracturing and grain ‘plucking’ at 20 mm from the impact point. Internal fracture intensity decreased with distance from the centre of the crater. Volumes around the impact point are therefore at greater risk of subsequent weathering deterioration, but significant damage extends to the periphery of the target, rendering whole blocks vulnerable. The surface crater, despite being one of the most conspicuous aspects of conflict damage, has many times less area than internal and surface fractures.
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Desbois, Guillaume, Nadine Höhne, Janos L. Urai, Pierre Bésuelle y Gioacchino Viggiani. "Deformation in cemented mudrock (Callovo–Oxfordian Clay) by microcracking, granular flow and phyllosilicate plasticity: insights from triaxial deformation, broad ion beam polishing and scanning electron microscopy". Solid Earth 8, n.º 2 (9 de marzo de 2017): 291–305. http://dx.doi.org/10.5194/se-8-291-2017.
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Abstract. The macroscopic description of deformation and fluid flow in mudrocks can be improved by a better understanding of microphysical deformation mechanisms. Here we use a combination of scanning electron microscopy (SEM) and broad ion beam (BIB) polishing to study the evolution of microstructure in samples of triaxially deformed Callovo–Oxfordian Clay. Digital image correlation (DIC) was used to measure strain field in the samples and as a guide to select regions of interest in the sample for BIB–SEM analysis. Microstructures show evidence for dominantly cataclastic and minor crystal plastic mechanisms (intergranular, transgranular, intragranular cracking, grain rotation, clay particle bending) down to the nanometre scale. At low strain, the dilatant fabric contains individually recognisable open fractures, while at high strain the reworked clay gouge also contains broken non-clay grains and smaller pores than the undeformed material, resealing the initial fracture porosity.
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Wang, Jingyi, Qinhong Hu, Mengdi Sun, Zhongxian Cai, Cong Zhang y Tao Zhang. "Micro- and Nanoscale Pore Structure Characterization of Carbonates from the Xiaoerbulake Formation in the Tarim Basin, Northwest China". Geofluids 2021 (27 de abril de 2021): 1–20. http://dx.doi.org/10.1155/2021/6667496.
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The evaluation of pore structure is an essential part in the assessment of carbonate reservoirs. The structures (geometry and connectivity) of nm to μm-scale pore networks in outcrop samples of carbonates from Xiaoerbulake Formation in Tarim Basin of China were studied by using optical microscopy, field emission-scanning electron microscopy (FE-SEM), as well as mercury intrusion porosimetry (MIP) with fractal analyses of the data, and spontaneous imbibition tests (distilled water). The results demonstrate that the lithologies are micritic dolomites, fine-to-medium-to-coarse crystalline dolomites, microbial dolomites, and dolarenite. At micro- to nanoscales in size, pore types are dominated by intergranular, intercrystalline, and intragranular (e.g., dissolution) pores. These pore networks have pore-throat diameters from 0.01 to >10 μm. Compared with a nanoscale pore network, the μm-scale pore networks are relatively well connected and serve as the most important permeability pathways. Although the pore volume accounts for most of the total porosity, the permeability of nanoscale pore networks is low. The existence of micro-nano-fractures could improve connectivity, especially for the nanoscale pore networks, by linking the intragranular (dissolution) pores which are mostly in the range of nm-scale.
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DJAMAL, BOUTASSOUNA, RENÉ LE GALL y IBEN KHALDOUN LEFKAIER. "EFFECT OF SMALL BULK SULFUR CONTENT AND ANNEALING TEMPERATURE ON THE INTERGRANULAR FRACTURING SUSCEPTIBILITY OF METALLIC NICKEL". Surface Review and Letters 23, n.º 06 (17 de noviembre de 2016): 1650050. http://dx.doi.org/10.1142/s0218625x16500505.
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In this paper, we investigate the influence of temperature on the nickel grain boundary equilibrium segregation of sulfur and the resulting intergranular fracturing susceptibility. Auger electron spectroscopy has been used to study equilibrium segregation of sulfur to the grain boundaries of a metallic nickel, with a mass bulk content of 3.6[Formula: see text]ppm in sulfur. Samples were first annealed at adequate temperatures for sufficiently large equilibrium time, and then quenched in water at room temperature. The analysis carried out shows a significant increase of sulfur concentration in the grain boundary with decreasing temperature. However, the sulfur content in the grain boundary shows a drastic shrink at 700[Formula: see text]C. This can be interpreted by the formation of an aggregate sulfide compound in the area of the grain boundaries. At 650[Formula: see text]C, in situ brittle fracture becomes unworkable and only intragranular fractures are observed. Using the results obtained through the investigation of the grain boundaries by Auger spectroscopy, the standard segregation energy is estimated as [Formula: see text].
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Crompton, Jeff W., Gwenn E. Flowers y Brendan Dyck. "Characterization of glacial silt and clay using automated mineralogy". Annals of Glaciology 60, n.º 80 (diciembre de 2019): 49–65. http://dx.doi.org/10.1017/aog.2019.45.
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AbstractGlacial erosion produces vast quantities of fine-grained sediment that has a far-reaching impact on Earth surface processes. To gain a better understanding of the production of glacial silt and clay, we use automated mineralogy to quantify the microstructure and mineralogy of rock and sediment samples from 20 basins in the St. Elias Mountains, Yukon, Canada. Sediments were collected from proglacial streams, while rock samples were collected from ice marginal outcrops and fragmented using electrical pulse disaggregation. For both rock fragments and sediments, we observe a log-normal distribution of grain sizes and a sub-micrometer terminal grain size. We find that the abrasion of silt and clay results in both rounding and the exploitation of through-going fractures. The abundance of inter- versus intragranular fractures depends on mineralogy and size. Unlike the relatively larger grains, where crushing and abrasion are thought to exploit and produce discrete populations of grain sizes, the comminution of fines leads to a grain size, composition and rounding that is continuously distributed across size, and highly dependent on source-rock properties.
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Hentschel, Felix, Claudia A. Trepmann y Emilie Janots. "Deformation of feldspar at greenschist facies conditions – the record of mylonitic pegmatites from the Pfunderer Mountains, Eastern Alps". Solid Earth 10, n.º 1 (17 de enero de 2019): 95–116. http://dx.doi.org/10.5194/se-10-95-2019.
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Abstract. Deformation microstructures of albitic plagioclase and K-feldspar were investigated in mylonitic pegmatites from the Austroalpine basement south of the western Tauern Window by polarized light microscopy, electron microscopy and electron backscatter diffraction to evaluate feldspar deformation mechanisms at greenschist facies conditions. The main mylonitic characteristics are alternating almost monophase quartz and albite layers, surrounding porphyroclasts of deformed feldspar and tourmaline. The dominant deformation microstructures of K-feldspar porphyroclasts are intragranular fractures at a high angle to the stretching lineation. The fractures are healed or sealed by polyphase aggregates of albite, K-feldspar, quartz and mica, which also occur along intragranular fractures of tourmaline and strain shadows around other porphyroclasts. These polyphase aggregates indicate dissolution–precipitation creep. K-feldspar porphyroclasts are partly replaced by albite characterized by a cuspate interface. This replacement is interpreted to take place by interface-coupled dissolution–precipitation driven by a solubility difference between K-feldspar and albite. Albite porphyroclasts are replaced at boundaries parallel to the foliation by fine-grained monophase albite aggregates of small strain-free new grains mixed with deformed fragments. Dislocation glide is indicated by bent and twinned albite porphyroclasts with internal misorientation. An indication of effective dislocation climb with dynamic recovery, for example, by the presence of subgrains, is systematically missing. We interpret the grain size reduction of albite to be the result of coupled dislocation glide and fracturing (low-temperature plasticity). Subsequent growth is by a combination of strain-induced grain boundary migration and formation of growth rims, resulting in an aspect ratio of albite with the long axis within the foliation. This strain-induced replacement by nucleation (associated dislocation glide and microfracturing) and subsequent growth is suggested to result in the observed monophase albite layers, probably together with granular flow. The associated quartz layers show characteristics of dislocation creep by the presence of subgrains, undulatory extinction and sutured grain boundaries. We identified two endmember matrix microstructures: (i) alternating layers of a few hundred micrometres' width, with isometric, fine-grained feldspar (on average 15 µm in diameter) and coarse-grained quartz (a few hundred micrometres in diameter), representing lower strain compared to (ii) alternating thin layers of some tens of micrometres' width composed of fine-grained quartz (<20 µm in diameter) and coarse elongated albite grains (long axis of a few tens of micrometres) defining the foliation, respectively. Our observations indicate that grain size reduction by strain-induced replacement of albite (associated dislocation glide and microfracturing) followed by growth and granular flow simultaneous with dislocation creep of quartz are playing the dominating role in formation of the mylonitic microstructure.
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Zhong, Liqiong, Hao Hu, Yilong Liang y Chaowen Huang. "High Cycle Fatigue Performance of Inconel 718 Alloys with Different Strengths at Room Temperature". Metals 9, n.º 1 (21 de diciembre de 2018): 13. http://dx.doi.org/10.3390/met9010013.
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In this paper, the high cycle fatigue performance of solid solution state and aged Inconel 718 superalloys was studied at room temperature. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to analyze the original structural features and fatigue deformation features of two kinds of alloys. SEM, laser scanning confocal microscopy, and electron backscatter diffraction (EBSD) were used to analyze the secondary fracture features of the fatigue fracture morphology and fatigue fracture profile. The results showed that the aging treatment significantly affected the strength and plasticity of the alloy, which in turn affected the fatigue performance of the alloy. After the aging treatment, the yield strength σs and the tensile strength σb of the Inconel 718 alloy increased by 152% and 65.9%, respectively, compared with those of the solid solution state, but the rate of elongation δ and rate of contraction in the cross-section area φ decreased by 63.7% and 52.3%, respectively. The fatigue limit of the aged state was lower than that of the solid solution state by 6.3%. The quadratic function relationship between the high cycle fatigue limit σ−1 and the tensile strength σb of the Inconel 718 superalloy at room temperature was σ−1 = σb · (0.869−3.67 × 10−4 · σb). An analysis of the fatigue fracture mechanism showed that the fatigue fractures before and after aging were all initiated in the grains oriented relatively unfavorably on the surface of the sample, with a mixture of intergranular and transgranular propagation after the transgranular propagation of several grains. The higher plasticity of the solid solution state Inconel 718 alloy resulted in a large number of slip deformation zones under high cycle fatigue loads, and the plastic deformation was relatively uniform. The lengths of the secondary fractures were as high as 120 μm, which formed the single-source plastic fatigue fracture that promoted an increase in the fatigue limit. After aging treatment, the higher strength of the Inconel 718 alloy made dislocation slip difficult under high cycle fatigue loads, and the plasticity compatible deformation capability was poor. When local dislocations slipped to the intragranular γ” phase, γ’ phase, or interfaces with nonmetallic compounds (NMCs), plugging occurred. The degree of stress concentration increased, causing the initiation of fatigue fracture; the secondary fracture was approximately 20 μm. Brittle cleavage due to multiple sources significantly reduced the fatigue limit.
Tesis sobre el tema "Intragranular Fractures"
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Ling, Chao. "Simulation de la rupture ductile intragranulaire des aciers irradiés. Effets de l'anisotropie cristalline et du gradient de déformations". Thesis, Paris Sciences et Lettres (ComUE), 2017. http://www.theses.fr/2017PSLEM018/document.
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L'irradiation peut modifier les propriétés mécaniques des aciers inoxydables austénitiques. Une diminution de la ténacité à la rupture des aciers en fonction de la dose est observée. La rupture ductile due à la croissance et la coalescence des cavités est toujours un mécanisme dominant dans les aciers irradiés jusqu'à 10 dpa. Des cavités peuvent être crées de manière différente : nucléées à partir des inclusions ou des précipités d'irradiation, ou créées directement par irradiation. Cette thèse a pour objectif d'étudier la rupture ductile des aciers irradiés due à la croissance et la coalescence des cavités intragranulaires. Basée sur la plasticité cristalline, des simulations en éléments finis sont effectuées sur les cellules unitaires pour étudier l'effet de l'orientation cristallographique et de la triaxialité de contraintes sur la croissance et la coalescence des cavités. L'effet de l'écrouissage post-irradiation sur la croissance et la coalescence des cavités est étudié avec un modèle de la plasticité cristalline prenant compte des défauts d'irradiation. En outre, un modèle élastomère-visco-plastique en grandes transformations est proposé pour décrire la croissance des cavités dans le monocristal. Le modèle est appliqué à la simulation de l'endommagement ductile dans le monocristal et le polycristal. Des cavités peuvent avoir des tailles différentes et la taille peut avoir une influence sur la ténacité à la rupture des aciers. Afin d'étudier cet effet, un modèle micromorphe de plasticité cristalline est proposé et appliqué à la simulation de la croissance et la coalescence des cavités intragranulaires de différentes tailles ainsi qu'aux phénomènes de localisation dans les monocristauxIrradiation causes drastic modifications of mechanical properties of austenitic stainless steels and a decrease in the fracture toughness with irradiation has been observed. Ductile fracture due to void growth and coalescence remains one dominant fracture mechanism for doses in the range of 0-10 dupa. Voids may have different origins : nucleated at inclusions or irradiation-induced precipitates during mechanical loading, or produced directly by irradiation. The present work is to investigate ductile fracture of irradiated steels due to growth and coalescence of intragranulaire voids. Based on continuum crystal plasticity theory, FE simulations are performed on unit cells for studying effects of lattice orientation and stress triaxiality on void growth and coalescence. The influence of post-irradiation hardening/softening on void growth ans coalescence is evaluated with a physically based crystal plasticity model. Besides, an elastoviscoplastic model at finite strains is proposed to describe void growth up to coalescence in single crystals, and is assessed based unit cell simulations. The model is then applied to simulate ductile damage in single crystals ans polycrystals. As voids in irradiated steels may have different origins, they may have different sizes, which potentially have an influence on ductile fracture process and fracture toughness of irradiated steels. In order to assess the size effect, a micromorphic crystal plasticity model is proposed and applied to simulate growth and coalescence of intragranular voids of different sizes
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Ayyildiz, Muhammed. "Scales Depencence of Fracture Density and Fabric in the Damage Zone of a Large Displacement Continental Transform Fault". Thesis, 2012. http://hdl.handle.net/1969.1/148095.
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Characterization of fractures in an arkosic sandstone from the western damage zone of the San Andreas Fault (SAF) at San Andreas Fault Observatory at Depth (SAFOD) was used to better understand the origin of damage and to determine the scale dependence of fracture fabric and fracture density. Samples for this study were acquired from core taken at approximately 2.6 km depth during Phase 1 drilling at SAFOD. Petrographic sections of samples were studied using an optical petrographic microscope equipped with a universal stage and digital imaging system, and a scanning electron microscope with cathodoluminescence (SEM-CL) imaging capability. Use of combined optical imaging and SEM-CL imaging was found to more successfully acquire true fracture density at the grain scale. Linear fracture density and fracture orientation were determined for transgranular fractures at the whole thin section scale, and intragranular fractures at the grain scale. The microscopic scale measurements were compared to measurements of mesoscopic scale fractures in the same core, as well as to published data from an ancient, exhumed trace of the SAF in southern California. Fracturing in the damage zone of the SAF fault follows simple scaling laws from the grain scale to the km scale. Fracture density distributions in the core from SAFOD are similar to distributions in damaged arkosic sandstone of the SAF along other traces. Transgranular fractures, which are dominantly shear fractures, indicate preferred orientation approximately parallel to the dominant sets of the mesoscale faults. Although additional work is necessary to confirm general applicability, the results of this work demonstrate that fracture density and orientation distribution over a broad range of scales can be determined from measurements at the mesoscopic scale using empirical scaling relations.
Capítulos de libros sobre el tema "Intragranular Fractures"
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"138. Mineral Reactions Participating in Intragranular Fracture Propagation: Subcritical Crack Growth ?" En Fault-related Rocks, 468–69. Princeton University Press, 1998. http://dx.doi.org/10.1515/9781400864935.468.
Texto completoActas de conferencias sobre el tema "Intragranular Fractures"
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Wu, X., S. Yandt y Z. Zhang. "A Framework of Integrated Creep-Fatigue Modeling". En ASME Turbo Expo 2009: Power for Land, Sea, and Air. ASMEDC, 2009. http://dx.doi.org/10.1115/gt2009-59087.
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A framework of integrated creep-fatigue (ICF) modeling is proposed based on the deformation decomposition rule that the total inelastic strain (in a polycrystalline material) consists of intragranular deformation (ID) and grain boundary sliding (GBS). With consideration of the respective deformation mechanisms, the resulting constitutive laws are given in 3D tensor forms such that fatigue damage (ID) and creep damage (GBS) are represented in different strain spaces, respectively. Then, the creep-fatigue life consumption can be evaluated using a physics-based formula that captures the intricate interaction between a propagating fatigue crack and distributed creep damage, leading to final fracture.
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Taylor, Kerry L., Andrew H. Sherry y Martin R. Goldthorpe. "Mechanically-Based Calibration of Ductile Fracture Models". En ASME 2008 Pressure Vessels and Piping Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/pvp2008-61048.
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Cracks in high pressure plant are often associated with welds, where residual stresses can enhance the crack driving force due to primary loading acting alone. One approach for taking account of the influence of residual stresses on defect behaviour in ductile materials is to use ductile damage mechanics. This paper presents a mechanistic study aimed at using metallographic and fractographic observations of as-received and tested material as the basis for calibrating of the Gurson ductile damage mechanics with a view to applying the calibrated model to predict residual stress effects on the ductile tearing behaviour of a high strength, low toughness 2024-T351 aluminium alloy. Detailed examination of notched tensile test specimens has clarified that two populations of second phase particles are involved in the failure process. Large intergranular intermetallic precipitates between 5 and 10 μm in diameter fracture at low strains, creating isolated microscale voids that grow under increasing plastic strain. Subsequently, a much finer array of intragranular precipitates approximately 100 to 500 nm in diameter fail at high plastic strains, leading to the formation of an almost instantaneous sheet of nanoscale voids that cause the sudden final failure of the material. Results are presented from a series of finite element analyses of these tests incorporating Gurson parameters associated with either the microscale or the nanoscale damage. These analyses demonstrate that modelling the nanoscale damage provides far better agreement with the experimental data that simulating the microscale damage. The implications of this observation on the modelling of pre-cracked specimens are discussed.
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Huang, C. Z., H. L. Liu, J. Wang y Z. W. Liu. "Study on Mechanical Properties of Multi-Scale and Multi-Phase Nanocomposite Ceramic Tool Materials". En ASME 2006 International Manufacturing Science and Engineering Conference. ASMEDC, 2006. http://dx.doi.org/10.1115/msec2006-21054.
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The single nano-scale and multi-phase nanocomposite ceramic materials including Al2O3/Al2O3n/SiCn and Al2O3/Ti(C0.7N0.3)n/SiCn are successfully fabricated. Their mechanical properties are better than those of the single-phase alumina material and conventional alumina matrix materials. The multi-scale and single-phase nanocomposite ceramic tool material Al2O3/SiCμ/SiCn is also successfully fabricated. Its flexural strength and fracture toughness is higher than those of single-scale materials Al2O3/SiCμ and Al2O3/SiCn. The multi-scale and multi-phase nanocomposite ceramic tool material Al2O3/TiCμ/TiNn is finally developed by incorporation and dispersion of micro-scale TiC particle and nano-scale TiN particle in alumina matrix, which can get higher flexural strength and fracture toughness than those of Al2O3/TiC ceramic tool material without nano-scale TiN particle. The coexistent function of nano-scale Al2O3 or Ti(C0.7N0.3), nano-scale SiC and TiN can reduce the sintering temperature and sintering duration time as well as the grain size, and improve the material densification and mechanical properties. The nano-scale SiC grains locating along the grain boundary and inside the micro-scale alumina can form the hybria intergranular-intragranular microstructure which can result in hybria intergranular-transgranular fracture and improve the mechanical properties of the ceramic material. Crack deflection, forking and bridging effects are the main cause for improving the fracture toughness of the materials including Al2O3/Ti(C0.7N0.3)n/SiCn and Al2O3/TiCμ/TiNn.