Bibliografias temáticas / Indentation cracking

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Literatura científica selecionada sobre o tema "Indentation cracking"

Autor: Grafiati

Publicado: 23 de novembro de 2024

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Artigos de revistas sobre o assunto "Indentation cracking"

Subhash, Ghatu, e Hongwen Zhang. "Dynamic indentation response of ZrHf-based bulk metallic glasses". Journal of Materials Research 22, n.º 2 (fevereiro de 2007): 478–85. http://dx.doi.org/10.1557/jmr.2007.0058.

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Static and dynamic Vickers indentations were performed on ZrHf-based bulk amorphous alloys. A decrease in indentation hardness was observed at higher strain rates compared with static indentation hardness. For equivalent loads, dynamic indentations produced more severe deformation features on the loading surface than static indentations. Using bonded interface technique, the induced shear band patterns beneath the indentations were studied. In static indentations, the majority of the deformation was primarily accommodated by closely spaced semicircular shear bands surrounding the indentation. In dynamic indentations two sets of widely spaced semicircular shear bands with two different curvatures were observed. The observed shear band patterns and softening in hardness were rationalized based on the variations in the confinement pressure, strain rate, and temperature within the indentation region during dynamic indentations. It is also proposed that free volume migration and formation of nano-voids leading to cracking are favored due to adiabatic heating and consequently cause the observed softening at high strain rates.

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Yamazaki, Yasuhiro. "Investigation of the Cracking Behaviors by Indentation Based on an In Situ Observation". Key Engineering Materials 627 (setembro de 2014): 361–64. http://dx.doi.org/10.4028/www.scientific.net/kem.627.361.

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In this paper, an in-situ measurement of crack size as a function of applied indentation load during indentation test was conducted. To perform the in-situ measurement, an instrumented indentation test machine with the in-situ observation system was developed and used. The joints of transparent ceramics by diffusion bonding were prepared as the specimen used in this study. The indentations were performed at the interface of the joints, and in the monolithic transparent ceramics by means of the instrumented indenter with the in-situ observation system. The relationship between crack shape and indentation load, as well as, the effect of the indenter shape on it were discussed.

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Abudaia, F. B., J. T. Evans e B. A. Shaw. "Spherical indentation fatigue cracking". Materials Science and Engineering: A 391, n.º 1-2 (janeiro de 2005): 181–87. http://dx.doi.org/10.1016/j.msea.2004.08.068.

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Newman, A., T. Jewett, S. Sampath, C. Berndt e H. Herman. "Indentation Response of Molybdenum Disilicide". Journal of Materials Research 13, n.º 9 (setembro de 1998): 2662–71. http://dx.doi.org/10.1557/jmr.1998.0371.

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The influence of microstructure on the indentation cracking behavior of molybdenum disilicide (MoSi2) has been examined. The indentation response of samples produced by various methods has been measured to examine the elastic/plastic nature, hardness, and fracture toughness. Fracture toughness comparisons were made by measuring indentation crack lengths, observing the elastic/plastic indentation response, and quantifying the differences in the indentation cracking behavior. Further information was gained by monitoring the acoustic activity during indentation for selected specimens. It has been observed that the fine grain size and the dispersion of the silica phase promote microcracking and crack deflection.

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Padture, Nitin P. "Postfailure subsidiary cracking from indentation flaws in brittle materials". Journal of Materials Research 8, n.º 6 (junho de 1993): 1411–17. http://dx.doi.org/10.1557/jmr.1993.1411.

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Vickers indentation sites in ceramics have been examined after specimen failure from median/radial indentation cracks. Evolution of a new cracking pattern of “ortho-lateral” cracks, originating at the intact corners of the Vickers indentation and running orthogonal to the classic-lateral cracks and parallel to the new fracture surface, has been observed. In some instances postfailure extension of the classic-lateral cracks toward the surface was also observed. Enhanced residual tensile stress from relaxation of constraints on the indentation-plastic cavity by the generation of a fracture surface is postulated to drive the subsidiary cracking. A simple qualitative model to explain this phenomenon is presented. Possible implications of such postfailure subsidiary cracking on residual-stress-driven flaws, postmortem fractography, and wear in ceramics are discussed.

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Baran, G., W. Shin, A. Abbas e S. Wunder. "Indentation Cracking of Composite Matrix Materials". Journal of Dental Research 73, n.º 8 (agosto de 1994): 1450–56. http://dx.doi.org/10.1177/00220345940730080901.

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Composite restorative materials wear by a fatigue mechanism in the occlusal contact area. Here, tooth cusps and food debris cyclically indent the restoration. Modeling this phenomenon requires an understanding of material response to indentation. The question in this study was whether material response depends on indenter size and geometry, and also, whether polymers used in restorative materials should be considered elastic and brittle, or plastic and ductile for modeling purposes. Three resins used as matrices in proprietary restorative composites were the experimental materials. To ascertain the influence of glass transition temperature, liquid sorption, and small amounts of filler on indentation response, we prepared materials with various degrees of cure; some samples were soaked in a 50/50 water/ethanol solution, and 3 vol% silica was added in some cases. Indentation experiments revealed that no cracking occurred in any material after indentation by Vickers pyramid or spherical indenters with diameters equal to or smaller than 0.254 mm. Larger spherical indenters induced subsurface median and surface radial and/or ring cracks. Critical loads causing subsurface cracks were measured. Indentation with suitably large spherical indenters provoked an elastoplastic response in polymers, and degree of cure and Tg had less influence on critical load than soaking in solution. Crack morphology was correlated with yield strain. Commonly held assumptions regarding the brittle elastic behavior of composite matrix materials may be incorrect.

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Sellappan, P., T. Rouxel, F. Celarie, E. Becker, P. Houizot e R. Conradt. "Composition dependence of indentation deformation and indentation cracking in glass". Acta Materialia 61, n.º 16 (setembro de 2013): 5949–65. http://dx.doi.org/10.1016/j.actamat.2013.06.034.

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Jiang, L. Z., e C. T. Sun. "Analysis of indentation cracking in piezoceramics". International Journal of Solids and Structures 38, n.º 10-13 (março de 2001): 1903–18. http://dx.doi.org/10.1016/s0020-7683(00)00142-6.

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Buijs, Maarten, e Liesan A. A. G. Martens. "Effect of Indentation Interaction on Cracking". Journal of the American Ceramic Society 75, n.º 10 (outubro de 1992): 2809–14. http://dx.doi.org/10.1111/j.1151-2916.1992.tb05509.x.

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Cook, Robert F., e Eric G. Liniger. "Kinetics of Indentation Cracking in Glass". Journal of the American Ceramic Society 76, n.º 5 (maio de 1993): 1096–105. http://dx.doi.org/10.1111/j.1151-2916.1993.tb03726.x.

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Mais fontes

Teses / dissertações sobre o assunto "Indentation cracking"

Bourguignon, Matthieu. "Borosilicate glasses : from viscoplasticity to indentation cracking ?" Electronic Thesis or Diss., Sorbonne université, 2024. http://www.theses.fr/2024SORUS247.

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Comprendre les mécanismes de rupture des verres est d'une importance cruciale en raison des vastes applications industrielles de ces matériaux, où la maîtrise de leurs propriétés mécaniques détermine leur performance et leur durabilité. L'examen approfondi des mécanismes de plasticité sous indentation dans les verres aluminoborosilicatés a mis en évidence le rôle déterminant de la composition chimique sur le comportement mécanique et à la rupture. Il est apparu que la présence et la concentration relative de modificateurs de réseau tels que les oxydes alcalino-terreux, ou bien une plus grande concentration de bore en tant que formateur de réseau, influencent significativement l'écoulement plastique localisé sous forme de bandes de cisaillement ainsi que la résistance à l'initiation et à la propagation des fissures, suggérant que des ajustements précis de la composition peuvent améliorer la résistance de ces matériaux face aux sollicitations mécaniques. D'autre part, un ensemble de caractérisations mécaniques et thermiques de ces verres a permis d'établir des premières corrélations entre leur structure et leur comportement mécanique sous indentation. Par ailleurs, l'étude de l'effet de l'irradiation électronique sur la plasticité des verres silicatés a révélé que l'exposition aux électrons peut accroître la sensibilité de ces matériaux à la déformation plastique, modifiant leur structure microscopique et leurs propriétés mécaniques. Il s'est avéré que l'irradiation électronique catalyse les réarrangements structuraux, sous contrainte, liés à la plasticité, entraînant une nette diminution de la limite d'élasticité du verre silicaté. Ces modifications ont été analysées à travers des modèles avancés de relaxation et de déformation, permettant de quantifier et de prévoir l'impact de l'irradiation sur le comportement des verres. Ces travaux contribuent à la compréhension des processus de plasticité dans les verres et ouvrent la voie à des stratégies d'optimisation de leurs propriétés mécaniques, notamment en concevant des compositions spécifiques pour renforcer leur résistance dans des environnements industriels exigeants ou soumis à des conditions sévères
Understanding the mechanisms of glass fracture is crucial due to the extensive industrial applications of these materials, where the control of their mechanical properties is key to ensuring performance and durability. In-depth examination of plasticity mechanisms under indentation in aluminoborosilicate glasses has highlighted the critical role of chemical composition in mechanical behavior and crack resistance. It has been observed that the presence and relative concentration of network modifiers, such as alkaline earth oxides, or a higher concentration of boron as a network former, significantly influence localized plastic flow in the form of shear bands, as well as the resistance to crack initiation and propagation. This suggests that precise adjustments in composition can enhance the material's resilience under mechanical stress. Additionally, a series of mechanical and thermal characterizations of these glasses have established correlations between their structure and mechanical behavior under indentation. Furthermore, the study of the effects of electron irradiation on the plasticity of silicate glasses revealed that exposure to electrons can increase these materials' susceptibility to plastic deformation, altering their microscopic structure and mechanical properties. It was found that electron irradiation catalyzes structural rearrangements under stress, leading to a marked decrease in the yield stress of silicate glasses. These changes were analyzed through advanced relaxation and deformation models, allowing for the quantification and prediction of irradiation's impact on glass behavior. This work advances the understanding of plasticity processes in glasses and paves the way for strategies to optimize their mechanical properties, particularly by designing specific compositions to enhance their resistance in demanding industrial environments or under severe conditions

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Sellappan, Pathikumar. "Indentation cracking of glass : role of the composition and reinforcement by diamond particles". Rennes 1, 2011. http://www.theses.fr/2011REN1S018.

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Le présent travail porte sur la problématique de l’initiation de fissure pour des familles de verres à base d’oxyde, d’oxynitrure et d’oxycarbure. En particulier, notre attention s’est portée sur la relation entre la composition chimique et les propriétés mécaniques (élasticité, dureté…). La résistance à l’initiation de fissure est étudiée en appliquant une charge de contact (en utilisant un indenteur diamant de type Vickers) sur une surface de verre polie. Des charges allant de quelques mN à 196 N furent appliquées et les empreintes furent analysées à l’aide d’un microscope optique, d’un MEB et d’un AFM. Plus le matériau se déforme (de manière permanente) sous l’indenteur, plus sa résistance à l’initiation de fissure est grande. La densification décroit avec l’accroissement de la taille des cations modificateurs pour les séries de verres silicatés à base d’oxydes. Nous avons également étudié l’influence des particules de diamant sur le comportement de composites SiOC (matrice) – Diamant (particules). L’ajout de particules de diamants de 2 μm (20 vol%) entraine un accroissement de la dureté et de la ténacité (technique SENB) respectivement d’un facteur 2 et 4. La charge nécessaire à l’initiation de fissure avec un indenteur Vickers passe alors de 2,903 N à 49,03 N
The present investigation deals with the crack initiation behavior of glasses from oxide based, oxynitride and also oxycarbide families. In particular, the relationship between chemical composition and mechanical properties (elasticity, hardness…) are investigated. The resistance to crack initiation is found by applying contact loading (using Vickers diamond indenter) on the polished surfaces of glasses. Loads ranging from few mN to 196 N were applied and the imprints were analyzed using optical/SEM and AFM microscopes. The more the material deforms (permanently) beneath the indenter, the larger is the resistance it offers to crack initiation. Densification decreases with increasing the size of the modifier cation in silica based oxide glass series. We also studied the influence of diamond particles on the deformation behavior of silicon oxycarbide glass. The addition of 2 μm size (20 vol%) diamond particles leads to an increment of hardness and fracture toughness (SENB technique) by a factor of 2 and 4, respectively. It also influenced the load required for crack initiation under Vickers indenter, increasing it from 2. 903 to 49. 03 N

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Bruns, Sebastian [Verfasser], Karsten [Akademischer Betreuer] Durst e Dominique de [Akademischer Betreuer] Ligny. "The Indentation Densification and Cracking Behavior of Fused Silica / Sebastian Bruns ; Karsten Durst, Dominique de Ligny". Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2020. http://nbn-resolving.de/urn:nbn:de:tuda-tuprints-117784.

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Bruns, Sebastian [Verfasser], Karsten [Akademischer Betreuer] Durst e Ligny Dominique [Akademischer Betreuer] de. "The Indentation Densification and Cracking Behavior of Fused Silica / Sebastian Bruns ; Karsten Durst, Dominique de Ligny". Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2020. http://d-nb.info/1212584147/34.

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Barbier, Christophe. "On folding of coated papers". Doctoral thesis, KTH, Solid Mechanics, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-28.

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The mechanical behaviour of coated papers during folding has been investigated. This problem has been studied with experimental techniques and numerical analyses in order to give a better understanding of the folding properties of coated papers pertinent to the mechanical behaviour in general, and particularly cracking along the fold.

A microscopy investigation has been performed. The surface of the folded paper has been carefully examined to study the event of fracture and related issues. The influence of the grammage on the cracking event has been studied and it was shown that the coating material would not fail if the paper sample was sufficiently thin. It was found that a stress or strain based criterion is sufficient to describe the cracking of the coating layers and that the anisotropy of paper should be taken into account when studying the folding process.

The finite element method has been used for the numerical analyses remembering that the geometry of the problem is rather complicated, excluding a solution in analytical form. Using different constitutive models for the base stock, it has been shown that the deformation of the coated paper during folding is much governed by the paper substrate. The numerical results also suggested that particular forms of plastic anisotropy can substantially reduce the maximum strain levels in the coating. Furthermore, it has also been shown that delamination buckling, in the present circumstances, has a very small influence on the strain levels in the coating layer subjected to high tensile loading.

Dynamic effects have also been studied and it has been shown that a quasi-static analysis of the problem is sufficient in order to describe many of the important features related to cracking. An attempt to model strong anisotropy of paper has been presented and the results indicate that the large anisotropy in the thickness direction of coated papers needs to be taken into account in order to fully understand the mechanics of folding.

Finally, an experimental investigation has been presented in order to study if important mechanical properties of the coating material could be determined by microindentation techniques. The results presented indicate that microindentation can be a powerful tool for characterization of these materials, but only if careful efforts are made in order to account for the influence from plasticity as well as from boundary effects.

KEYWORDS: folding, coated papers, finite element method, cracking, indentation, anisotropy, plasticity.

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Razzaq, Abdur. "Plastic deformation around indentations and their effect on fatigue cycling". Thesis, University of Surrey, 1988. http://epubs.surrey.ac.uk/843009/.

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It is now a well established fact that fatigue cracks initiate from persistent slip bands (PSBs). Previous work on copper fatigued in reverse bending has revealed that the PSBs form much earlier near indentations or surface pits than in regions well away from them. The cause of this effect has been attributed partly to a dislocation microstructure introduced by the indentations as well as possible contribution from the residual stresses resulting from them and geometric stress raising effects. To study this phenomenon in a greater depth, an attempt has been made to make a comprehensive study of the plastic deformation around indentations and to study their effect on the low ampltude fatigue cycling of mono and polycrystalline copper. This effect has been studied using both surface as well as Transmission Electron Microscope (TEM) observations. The project was divided into four main categories; a study of the deformation around indentations; a study of the fatigue cycling mechanism; a study of the low strain amplitude fatigue cycling of the indented specimens and a study of the effect of indentation on the fatigued specimens. The surface topographical studies were made on specially designed polycrystalline and single crystal specimens of copper. The transmission electron microscope study has been done mainly on thin strips sliced and prepared from two bulk single crystals with axial orientation close to [124] and [012]. The dislocation structures due to indentations were studied in regions at different positions in relation to the indentations and included a study of the microstructures close to the surface as well as ~ 50mum from it. Specimens were fatigued in air, at room temperature, at total strain amplitudes in the range = 2x10-4 to 9.8x10-4 for bulk specimens and a 0.8x10-3 to 1.9x10-3 for thin foil specimens. The number of fatigue cycles given to the specimens varied (from specimen to specimen) from a few cycles to several hundred thousand cycles. The Dyer model (1965) has been satisfactorily extended from ball to pyramid indentations to explain the hill formation and the general surface topography around indentations. Dislocation, microstructures around indentations in the 'indented' and 'indented and fatigued' specimens of the same orientation have been analysed and compared. Such an analysis has revealed that in the regions of indentations in which PSBs are initiated more readily, the dislocation microstructure due to indentation contained predominantly the Burgers vectors +/-a/2 [110] or +/-a/2 [011] and +/-a/2 [110] or +/-a/2 [011]. In contrast to these, the most frequently found Burgers vectors in the same regions of the indentation followed by fatigue were +/-a/2 [101] and +/-a/2 [011], which reveals that the Burgers vectors of the dislocations introduced by the indentation in these regions are quite favourable for the later stage of fatigue cycling, with an enhanced density of dislocations. A little work was also done to study the effect of the indentations made in the fatigued specimens. It has showed an enhancement of the inhomogeneous and anisotropic deformation around the indentations caused by fatigue cycling as well as a significantly different type of slip bands.

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Sun, Xiaodan. "Residual stresses, cracking and stress intensity factors for Vickers indentations in ceramics". Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:71f1d3ed-8163-4487-a81e-df09d50710ed.

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Vickers hardness indentations on AI2O3 were studied comprehensively. Beneath indentation, there is a well-defined interface between the plastic zone and the elastic region and the radius of the plastic zone is close to half the indentation diagonal length. The residual stress field around the indentations has been measured by optical fluorescence microscope (FLM) scans. Yoffe's stress model predicted higher stresses than the experimental stress results. the radial crack lengths were measured by FLM scans, and the optical microscope (OM) and SEM methods for crack length measurements were found to significantly underestimate the crack lengths. Post indentation slow crack growth was found on the radial cracks were determined. The radial-median crack system was found for alumina indentations. Lateral cracks were also found for all the indentations, and their depths were close to the half diagonal lengths. the lateral cracks joined the tips of the radial cracks and had the similar growth rates to the radial cracks. The indentation parameters of SiC and 3Y-TZP indentations were also measured. Lateral cracking was observed beneath in SiC indentations but not in case of 3Y-TZP. The depth of the lateral crack of the SiC indentation was found to be close to the half diagonal length. the residual stresses and surface profiles around SiC and 3Y-TZP indentations were measured. the lateral crack lengths of the SiC determined from the surface profiles were close to the radial crack lengths. For TZP indentations, the highest volume fraction of the monoclinic zirconia phase was found near the edge of the indentations. Surface uplifts around indentations were found to have the profiles matching with distributions of the volume fraction of the monoclinic phase. A new Vickers indentation residual stress model has been presented using assumptions based on the experimental findings on alumina indentations. The main novelty of the model is that it predicts the stresses in the presence of cracking, and is therefore testable. The residual stress model has successfully predicted the stress fields around the polycrystalline alumina and SiC indentations but failed on TZP indentations because of the lack of lateral cracking and the tetragonal-to-monoclinic phase transformation. From the residual stress model, a new formula for the indentation stress intensity factor K was derived, which provided good results for threshold stress intensity factor, K10, on alumina, and fracture toughness, KIC, for SiC, and Si3N4. Three adjustable parameters can be added to strengthen existing model.

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Strömbro, Jessica. "Micro-mechanical mechanisms for deformation in polymer-material structures". Doctoral thesis, KTH, Hållfasthetslära (Inst.), 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4626.

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In this thesis, the focus has been on micro-mechanical mechanisms in polymer-based materials and structures. The first part of the thesis treats length-scale effects on polymer materials. Experiments have showed that the smaller the specimen, the stronger is the material. The length-scale effect was examined experimentally in two different polymers materials, polystyrene and epoxy. First micro-indentations to various depths were made on polystyrene. The experiments showed that length-scale effects in inelastic deformations exist in polystyrene. It was also possible to show a connection between the experimental findings and the molecular length. The second experimental study was performed on glass-sphere filled epoxy, where the damage development for tensile loading was investigated. It could be showed that the debond stresses increased with decreasing sphere diameter. The debonding grew along the interface and eventually these cracks kinked out into the matrix. It was found that the length to diameter ratio of the matrix cracks increased with increasing diameter. The experimental findings may be explained by a length-scale effect in the yield process which depends on the strain gradients. The second part of the thesis treats mechano-sorptive creep in paper, i.e. the acceleration of creep by moisture content changes. Paper can be seen as a polymer based composite that consists of a network of wood fibres, which in its turn are natural polymer composites. A simplified network model for mechano-sorptive creep has been developed. It is assumed that the anisotropic hygroexpansion of the fibres leads to large stresses at the fibre-fibre bonds when the moisture content changes. The resulting stress state will accelerate creep if the fibre material obeys a constitutive law that is non-linear in stress. Fibre kinks are included in order to capture experimental observations of larger mechano-sorptive creep effects in compression than in tension. Furthermore, moisture dependent material parameters and anisotropy are taken into account. Theoretical predictions based on the developed model are compared to experimental results for anisotropic paper both under tensile and compressive loading at varying moisture content. The important features in the experiments are captured by the model. Different kinds of drying conditions have also been examined.
QC 20100910

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Bruns, Sebastian. "The Indentation Densification and Cracking Behavior of Fused Silica". Phd thesis, 2020. https://tuprints.ulb.tu-darmstadt.de/11778/1/Diss_Bruns_Revised.pdf.

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The damage resistance of glass is of great scientific and economic interest. In oxide glasses crack formation is closely related to the plastic deformation processes that occur under contact stress, i.e. shear flow or structural compression. In this context an increased crack resistance is often attributed to an increased compaction capacity. However, the influence of densification on crack initiation and expansion remains unclear. In the present work the influence of densification on cracking is investigated using both cohesive zone finite element modelling and nanoindentation testing with fused silica serving as model system for densifying oxide glass. The densification information from hydrostatic compaction experiments was implemented into the FEA using modified Drucker-Prager cap plasticity. Nanoindentation experiments with various tip geometries and Raman spectroscopy were used to quantify densification and cracking experimentally. The fracture toughness of fused silica was assessed by indentation cracking and micro pillar splitting techniques, finding values in good accordance with literature.

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Harding, David Scott. "Cracking in brittle materials during low-load indentation and its relation to fracture toughness". Thesis, 1995. http://hdl.handle.net/1911/19099.

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Nanoindentation is a widely recognized method for characterizing the mechanical properties of thin films and small volumes. This thesis reports the results of an investigation aimed at developing a technique by which the fracture toughness of a thin film or small volume can be determined from low-load indentation experiments. The method relies on the fact that most brittle materials form radial cracks when indented with a sharp indenter such as a Vickers indenter. The lengths of the radial cracks produced during microindentation experiments have been shown to correlate reasonably well with fracture toughness. As a result, simple semi-empirical relations have been developed to calculate fracture toughness based on the measurement of indentation crack length. The one problem encountered in applying the indentation cracking method for measuring fracture toughness to low loads is that there are threshold loads below which most materials do not form radial cracks. For Vickers and Berkovich indenters, the cracking threshold is 25 grams ($\sim$250 mN) or more for most ceramic and glass materials. It is shown that the problems imposed by the cracking threshold can largely be overcome by using an indenter with the geometry of a cube corner. With a cube corner indenter, the cracking threshold of most brittle materials can be reduced to loads as small as 0.1 gram ($\sim$1 mN). In addition, the well-developed relationships between indentation crack length and fracture toughness used for the Vickers indenter at high loads, generally above 1000 grams ($\sim$10 N), can be used with the cube corner indenter at very small loads, 0.1 gram ($\sim$1 mN) and above, provided different empirical constants are used. The Berkovich indenter, which is the three-sided analog of a Vickers indenter, is also found to obey the fracture toughness relations of the Vickers indenter. A model is developed which explains the differences in cracking thresholds for the Vickers, Berkovich, and cube corner indenters. The model is based on the hardness impression itself serving as the precursor flaw from which cracks extend.

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Capítulos de livros sobre o assunto "Indentation cracking"

Yonezu, Akio, e Xi Chen. "Hydrogen Embrittlement Cracking Produced by Indentation Test". In Handbook of Nonlocal Continuum Mechanics for Materials and Structures, 1–25. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-22977-5_23-1.

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Yonezu, Akio, e Xi Chen. "Hydrogen Embrittlement Cracking Produced by Indentation Test". In Handbook of Nonlocal Continuum Mechanics for Materials and Structures, 289–313. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-319-58729-5_23.

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Weppelmann, E., M. Wittling, M. V. Swain e D. Munz. "Indentation Cracking of Brittle Thin Films on Brittle Substrates". In Fracture Mechanics of Ceramics, 475–86. Boston, MA: Springer US, 1996. http://dx.doi.org/10.1007/978-1-4615-5853-8_36.

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Wade, James, Phoebe Claydon e Houzheng Wu. "Plastic Deformation and Cracking Resistance of SiC Ceramics Measured by Indentation". In Mechanical Properties and Performance of Engineering Ceramics and Composites IX, 91–100. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2014. http://dx.doi.org/10.1002/9781119031192.ch10.

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Tortorelli, P. F., J. R. Keiser, K. R. Willson e W. C. Oliver. "Effects of Reactive Elements on Oxide Scale Deformation and Cracking Based on Submicron Indentation Testing". In Microscopy of Oxidation, 271–77. London: CRC Press, 2023. http://dx.doi.org/10.1201/9781003422020-36.

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Yavas, Denizhan, Pratyush Mishra, Ashraf F. Bastawros, Kurt R. Hebert e Pranav Shrotriya. "Characterization of Sub-surface Damage During the Early Stage of Stress Corrosion Cracking by Nano Indentation". In Conference Proceedings of the Society for Experimental Mechanics Series, 37–44. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-42028-8_5.

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Mills, NJ. "Indentation, cracking, and fracture". In Polymer Foams Handbook, 351–71. Elsevier, 2007. http://dx.doi.org/10.1016/b978-075068069-1/50016-7.

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Trabalhos de conferências sobre o assunto "Indentation cracking"

Marimuthu, Karuppasamy Pandian, Felix Rickhey, Hyungyil Lee e Jin Haeng Lee. "Spherical indentation cracking in brittle materials: An XFEM study". In 2016 7th International Conference on Mechanical and Aerospace Engineering (ICMAE). IEEE, 2016. http://dx.doi.org/10.1109/icmae.2016.7549548.

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Ji-Peng, Liu, e Huang Gan-Yun. "Mechanical modeling of Lateral Cracking in Brittle Materials under Indentation". In 1st International Conference on Mechanical Engineering and Material Science). Paris, France: Atlantis Press, 2012. http://dx.doi.org/10.2991/mems.2012.53.

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Majzoub, R., e Mohammad M. Chaudhri. "Visualization of low-velocity dynamic indentation cracking of an epoxy and polymethylmethacrylate". In 25th international Congress on High-Speed photography and Photonics, editado por Claude Cavailler, Graham P. Haddleton e Manfred Hugenschmidt. SPIE, 2003. http://dx.doi.org/10.1117/12.516948.

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Berriche, R., R. K. Lowry e M. I. Rosenfield. "Evaluation of the Resistance of Individual Si Die to Cracking". In ISTFA 1998. ASM International, 1998. http://dx.doi.org/10.31399/asm.cp.istfa1998p0197.

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Abstract The present work investigated the use of the Vickers micro-hardness test method to determine the resistance of individual die to cracking. The results are used as an indicator of resistance to failure under the thermal and mechanical stresses of packaging and subsequent thermal cycling. Indentation measurements on die back surfaces are used to determine how changes in wafer backside processing conditions affect cracks that form around impressions produced at different loads. Test methodology and results obtained at different processing conditions are discussed.

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Subhash, Ghatu, Brian J. Koeppel, Richard J. Anton, Yonggang Y. Huang e Abhijit Chandra. "High Strain Rate Normal Indentation of Ceramics: Implications for Material Removal Mechanisms". In ASME 1997 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1997. http://dx.doi.org/10.1115/imece1997-0695.

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Abstract The static indentation fracture mechanics approach does not fully capture the rate sensitive nature of failure behavior in ceramics. Accordingly, a dynamic indentation technique was developed to investigate material removal mechanisms at strain rates similar to those encountered in realistic grinding situations. The technique is designed to deliver a single indentation load of duration 100 microseconds. Compared to static loading, it is observed that lateral cracking is promoted under dynamic loading rates. The implications of dynamic loading on the material removal mechanisms are discussed.

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Jar, Ben, e Yi Zhang. "Evaluation of a New Approach for Characterizing Environmental Stress Cracking Resistance (ESCR) of Polyethylene". In ASME 2016 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/pvp2016-63432.

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A study was conducted to develop a new approach for characterizing environmental stress cracking resistance (ESCR) of polyethylene (PE). The main objective is to reduce time for the testing, to be shorter than that required for the current standard ESCR tests. The new approach applies indentation to generate deflection in the central region of a PE plate, and uses time for crack generation under constant displacement, during the exposure to an aggressive agent, to characterize ESCR. The indentation introduces stretch to a central annular region around the indenter, in which PE molecules are increasingly oriented in the stretch direction. Since this annular region is subjected to bi-axial tension, exposure to aggressive agent increases its vulnerability to crack formation in the stretch direction. ESCR is characterized by the time needed for crack formation during the exposure to an aggressive agent (10% Igepal CO-630 solution). This paper presents the test set-up for the new approach, and compares time for the crack generation using this new approach with that from ASTM D1693, condition A.

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Tang, G., e Y. L. Shen. "Indentation Mechanics for Micro- and Nano-Layered Composites". In 2008 Second International Conference on Integration and Commercialization of Micro and Nanosystems. ASMEDC, 2008. http://dx.doi.org/10.1115/micronano2008-70038.

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The effect of micro- and nano-scale heterogeneity on the indentation behavior of the composite structure was studied numerically using the finite element method. The material system of concern is the aluminum (Al)/silicon carbide (SiC) multilayered thin films above the silicon (Si) substrate. The numerical model features the explicit composite structure indented by a conical diamond indenter within the axisymmetric simulation framework. Attention is devoted to the evolution of stress and deformation fields in the layered composite during the indentation loading and unloading processes. It was found that the layered composite, consisting of materials with distinctly different mechanical properties, results in unique deformation patterns. Significant tensile stresses can be generated locally along certain directions, which offers a mechanistic rationale for the indentation-induced internal cracking observed experimentally. The unloading process also leads to an expansion of the tension-stressed area, as well as continued plastic flow in parts of the Al layers. Implications of these numerical findings to the nanoindentation response of metal-ceramic laminates are discussed.

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Lu, Ping, e Kevin Chou. "Interface Delamination of Diamond-Coated Carbide Tools Considering Coating Fractures by XFEM". In ASME 2013 International Manufacturing Science and Engineering Conference collocated with the 41st North American Manufacturing Research Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/msec2013-1132.

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Interface delamination is the major failure mode of diamond-coated carbide tools in machining. On the other hand, coating cracking is possibly accompanied during a tribological process that induces the delamination phenomenon. However, such an influence between the two failure behaviors has not been investigated in a quantitative way to better understand and design diamond coating tools. In this study, a three-dimensional (3D) indentation model combining cohesive interactions and extended finite element method (XFEM) was developed to investigate the diamond-coating, carbide-substrate interface behavior with the incorporation of coating cracking. The interface interaction was based on a cohesive zone model (CZM) with a bilinear traction-separation law. XFEM was applied to the coating domain to model cracking in the diamond coating with a damage criterion of the maximum principal stress. Deposition stresses were also included to investigate their effect on the coating delamination and fractures. The model was implemented in finite element (FE) codes to analyze the cone crack in brittle coatings, as well as the interface delamination of diamond coated carbide tools. The XFEM model was validated by the indentation testing data from literature in crack initiations and propagations in brittle materials. FE results from the indentation on diamond-coated tools show that the interface delamination size and the loading force become smaller when coating fractures are incorporated in the model, and the deposition stresses will increase the initial crack radius as well as the critical load for delamination in diamond coatings.

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Nebel, J., E. Vogli e W. Tillmann. "Arc Spraying of WC-FeCSiMn Cored Wires – Part 1: Bending, Compression and Tension Behavior". In ITSC2010, editado por B. R. Marple, A. Agarwal, M. M. Hyland, Y. C. Lau, C. J. Li, R. S. Lima e G. Montavon. DVS Media GmbH, 2010. http://dx.doi.org/10.31399/asm.cp.itsc2010p0592.

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Abstract This is the first of two papers concerning the intrinsic mechanical properties of arc-sprayed WC-FeCSiMn coatings. In part 1 the elastic and plastic forming behavior of the layers are investigated by indentation, bending and tensile tests. They were performed on coated mild steel substrates as well as freestanding as-sprayed samples with different geometries. Considering the coatings microstructure, element and pore distribution, as well as the local microhardness the results of the indentation, bending, and tensile tests were evaluated. The critical role of pores and inhomogeneities within the sprayed coating was examined in detail. Micro- and macrocracking were investigated by SEM after the indentation and tensile tests. In-situ surface observation by optical 3D-microscopy was used to study the onset of cracking during the 3-point bending test.

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Bhagavat, Milind, Fuqian Yang e Imin Kao. "Elasto-Plastic Finite Element Analysis of Indentations in Free Abrasive Machining". In ASME 1998 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/imece1998-1097.

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Abstract Free abrasive machining (FAM) using a wiresaw is emerging as a state of the art technology for slicing large diameter semiconductor wafers. Material removal in a FAM environment is known to be by rolling and indenting of abrasives into the cut media. Therefore, indentation by abrasives in the slurry is the single most important mechanism in wiresawing process. This paper deals with the importance of abrasive shape in material removal during FAM. To achieve this objective, indentation by conical rigid abrasives of different included angles has been investigated using finite element method (FEM). Typical indentation fracture involving median, radial and transverse cracking has been explained to the maximum level of sophistication attainable using static stress analysis. Some industrially relevant results pertaining to FAM in general and wire-sawing in particular have been proposed.

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Relatórios de organizações sobre o assunto "Indentation cracking"

Rana, Arnav, Sanjay Tiku e Aaron Dinovitzer. PR-214-203806-R01 Improve Dent-Cracking Assessment Methods. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), junho de 2022. http://dx.doi.org/10.55274/r0012227.

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This work was funded in part, under the Department of Transportation, Pipeline and Hazardous Materials Safety Administration. The views and conclusions contained in this document are those of the authors and should not be interpreted as representing the official policies, either expressed or implied, of the Pipeline and Hazardous Materials Safety Administration, the Department of Transportation, or the U.S. Government. This project builds on mechanical damage (MD) assessment and management tools, developed on behalf of Pipeline Research Council International (PRCI), Interstate Natural Gas Association of America (INGAA), Canadian Energy Pipeline Association (CEPA), American Petroleum Institute (API), other research organizations and individual pipeline operators and were included in API RP 1183. These include dent shape, restraint condition and interacting feature characterization; operational maximum and cyclic internal pressure characterization, screening tools defining non-injurious dent shapes based on pipe size and operating condition, failure pressure and fatigue assessment tools for dents with/without interacting features (e.g., corrosion, welds, gouges) in the restrained and unrestrained condition, and direction on available remedial action and repair techniques. In completing this development, areas for improvement were identified. The current project enhances previously developed tools being adopted in an industry recommended practice (API RP 1183) for pipeline MD integrity assessment and management considering: - Enhancement of indentation crack formation strain estimation, - Understanding the role of ILI measurement accuracy on dent integrity assessment, and - Quantification of assessment method conservatism to support safety factor definition. Safety factors (Modeling bias) defined in the present study and evaluated for different fatigue life estimation approaches in the present work refer to the conservatism inherent in different in different fatigue life models and is represented as the ratio of experimental lives to predicted lives.

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