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Letteratura scientifica selezionata sul tema "Scratch tests"

Autore: Grafiati

Pubblicato: 29 marzo 2025

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Articoli di riviste sul tema "Scratch tests"

1

Shi, Xin Hong, e Mei Juan Shan. "Effect of Scratch Depths on Fatigue Properties of PMMA for Aircraft Canopies". Applied Mechanics and Materials 687-691 (novembre 2014): 81–84. http://dx.doi.org/10.4028/www.scientific.net/amm.687-691.81.

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A series of fatigue tests is performed for polymethyl methacrylate (PMMA) specimens without scratches and with scratches. The scratch depth is set to be 0.2mm, 0.3mm and 0.4mm, respectively. Based on the experimental results, it can be deduced that contained fatigue limit of specimens with scratches significantly decreases compared to specimens without scratches. Besides, contained fatigue limit decreases gradually with scratch depth increasing from 0.0mm to 0.4mm. Consequently, it can be concluded that fatigue properties of PMMA will decrease when there exists scratch and for scratch depth from 0.0mm to 0.4mm, fatigue property decreases remarkably with deeper scratch.

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2

Shi, Xin Hong, e Mei Juan Shan. "Effect of Scratch Depths on Tensile Strength of PMMA for Aircraft Canopies". Advanced Materials Research 1056 (ottobre 2014): 8–11. http://dx.doi.org/10.4028/www.scientific.net/amr.1056.8.

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Static tensile tests of polymethyl methacrylate (PMMA) specimens without scratches and containing a scratch whose depth was set to be 0.2mm, 0.3mm and 0.4mm, respectively, were carried out to explore effect of scratch depths on tensile strength of PMMA. Based on the experimental load-displacement curves, the specimens without scratches deform most severely when the failure comes forth. The failure deformation declines gradually with higher scratch depth, namely higher scratch depth leads to lower plastic deformation. It thus follows that the scratch significantly reduces the tensile strength of PMMA while the variation of the scratch depth from 0.2mm to 0.4mm has negligible influence on the tensile strength of PMMA.

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3

Zhao, Xu, Yadong Gong, Ming Cai e Bing Han. "Numerical and Experimental Analysis of Material Removal and Surface Defect Mechanism in Scratch Tests of High Volume Fraction SiCp/Al Composites". Materials 13, n. 3 (10 febbraio 2020): 796. http://dx.doi.org/10.3390/ma13030796.

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This paper addresses a comprehensive and further insight into the sensitivity of material removal and the surface defect formation mechanism to scratch depth during single-grit scratch tests of 50 vol% SiCp/Al composites. The three-dimensional (3D) finite element model with more realistic 3D micro-structure, particle-matrix interfacial behaviors, particle-particle contact behaviors, particle-matrix contact behaviors and a Johnson-Holmquist-Beissel (JHB) model of SiC was developed. The scratch simulation conducted at scratch velocity 10 mm/min and loading rate 40 N/min revealed that the scratch depth plays a crucial role in material removal and the surface forming process. Brittle fracturing of SiC particles and surface defects become more deteriorative under a large scratch depth ranging from 0.0385 to 0.0764 μm. The above phenomenon can be attributed to the influence of scratch depth on SiC particles’ transport; the increase in the amount of SiC particle transport resulting from an increase of scratch depth raises the occurrence of particle-particle collision which provides hard support and shock for the scratched particles; therefore, brittle fracturing gradually becomes the major removal mode of SiC particles as the scratch depth increases. On the deteriorative surface, various defects are observed; i.e., lateral cracks, interfacial debonding, cavies filled with residually broken particles, etc. The von Mises stress distribution shows that SiC particles bear vast majority of load, and thus present greater stress than the surrounding Al matrix. For example: their ratio of 3 to 30 under the scratch depth of 0.011 mm. Namely, SiC particles impede stress diffusion within the Al matrix. Finally, the SEM images of the scratched surface obtained from the single-grit scratch experiments verify the numerical analysis’s results.

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4

Duan, Miaomiao, Zhufeng Yue e Qianguang Song. "Effect of Superficial Scratch Damage on Tension Properties of Carbon/Epoxy Plain Weave Laminates". Advances in Civil Engineering 2021 (31 marzo 2021): 1–8. http://dx.doi.org/10.1155/2021/5590448.

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The effect of scratch damage on the tension properties of carbon fiber plain weave laminates has been studied in detail using digital image correlation (DIC) and acoustic emission (AE). A range of scratch lengths was machined onto different laminates. The bearing capacity of the laminates was then compared with that of unaltered samples. The strain field distributions near the scratches were measured and analyzed as a function of scratch length with DIC. Initiation and propagation of damage were monitored during the tensile tests using AE. Failure sites and morphologies were observed and analyzed. The results show that superficial scratches have little effect on the strength of plain weave laminates when the scratch length is less than 80% of the specimen width. Scratches affect the distribution of strain near the scratch but not far away from the scratch or at the back face of the sample. Not all samples broke from the scratch site but instead broke from the free edge of the sample or close to the gripping region.

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5

da Silva, Dayanne Lopes, Emanuel Santos, Sérgio de Souza Camargo e Antônio Carlos de Oliveira Ruellas. "Infrared spectroscopy, nano-mechanical properties, and scratch resistance of esthetic orthodontic coated archwires". Angle Orthodontist 85, n. 5 (24 novembre 2014): 777–83. http://dx.doi.org/10.2319/070314-472.1.

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ABSTRACT Objective: To evaluate the material composition, mechanical properties (hardness and elastic modulus), and scratch resistance of the coating of four commercialized esthetic orthodontic archwires. Materials and Methods: The coating composition of esthetic archwires was assessed by Fourier-transform infrared spectroscopy (FTIR). Coating hardness and elastic modulus were analyzed with instrumented nano-indentation tests. Scratch resistance of coatings was evaluated by scratch test. Coating micromorphologic characteristics after scratch tests were observed in a scanning electron microscope. Statistical differences were investigated using analysis of variance and Tukey post hoc test. Results: The FTIR results indicate that all analyzed coatings were markedly characterized by the benzene peak at about 1500 cm−1. The coating hardness and elastic modulus average values ranged from 0.17 to 0.23 GPa and from 5.0 to 7.6 GPa, respectively. Scratch test showed a high coating elasticity after load removal with elastic recoveries >60%, but different failure features could be observed along the scratches. Conclusion: The coatings of esthetic archwires evaluated are probably a composite of polyester and polytetrafluoroethylene. Delamination, crack propagation, and debris generation could be observed along the coating scratches and could influence its durability in the oral environment.

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6

Zhang, Xianlei, Kefan Jiao, Shaoshuai Ma e Yunyun Wu. "Effect of Scratches on Mechanical Properties and Impermeability of PVC-P Geomembranes". Polymers 17, n. 3 (22 gennaio 2025): 277. https://doi.org/10.3390/polym17030277.

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Plasticized polyvinyl chloride (PVC-P) geomembranes (GMBs) are susceptible to physical scratches due to improper construction in water conservancy projects. Axial tensile tests and permeability tests were carried out to investigate the mechanical properties and impermeability of PVC-P GMBs with scratches under various combinations of scratch angles, lengths, and depths. This was achieved by evaluating the break strength, break elongation, Young’s modulus, and permeability coefficient. The results demonstrated that physical scratches weaken the mechanical properties of PVC-P GMBs, and interactions among the influencing factors were observed. The influence of scratches on the break elongation and break strength outweighed that on Young’s modulus, with scratch depth exerting the most significant effect on the mechanical properties under identical conditions. The scratches on PVC-P GMBs should be minimized in practice, while those without penetrating cracks along the thickness direction and tensile deformation have negligible effects on impermeability. The failure threshold of PVC-P GMBs with scratches was determined, along with the scratch depths, angles, and lengths affecting the operation of the project. This provides a reference for assessing whether PVC-P GMBs with scratches jeopardize the safety of projects.

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7

Leung, H. M., e Sujeet K. Sinha. "Scratch and indentation tests on seashells". Tribology International 42, n. 1 (gennaio 2009): 40–49. http://dx.doi.org/10.1016/j.triboint.2008.05.015.

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8

Lin, Jeen-Shang, e Yaneng Zhou. "Can scratch tests give fracture toughness?" Engineering Fracture Mechanics 109 (settembre 2013): 161–68. http://dx.doi.org/10.1016/j.engfracmech.2013.06.002.

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9

Richard, Thomas, Fabrice Dagrain, Edmond Poyol e Emmanuel Detournay. "Rock strength determination from scratch tests". Engineering Geology 147-148 (ottobre 2012): 91–100. http://dx.doi.org/10.1016/j.enggeo.2012.07.011.

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10

Patzelt, B., e U. Hemmann. "Scratch-Tests zur Untersuchung der Abrasionsbeständigkeit". Materialwissenschaft und Werkstofftechnik 28, n. 10 (ottobre 1997): 500–504. http://dx.doi.org/10.1002/mawe.19970281013.

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Più fonti

Tesi sul tema "Scratch tests"

1

Krupicka, Andreas. "Use and interpretation of scratch tests on organic coatings". Doctoral thesis, KTH, Polymer Technology, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3357.

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2

Akono, Ange-Therese. "Scratch tests : a new way of evaluating the fracture toughness of materials". Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/64571.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2011.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 126-130).
This thesis develops, validates and implements a fracture mechanics model for the assessment of the fracture toughness of materials from scratch tests. Dimensional Analysis highlights two major processes at work during scratch tests: plastic yielding and fracture dissipation. An original set-up of controlled laboratory tests on paraffin wax allows us to identify fracture processes as predominant. An analytical model for scratch tests with a rectangular blade and a back-rake angle is then developed. This model applies to linear elastic isotropic brittle materials and links the fracture toughness to the average horizontal and vertical forces recorded in the scratch test, and to the width and depth of the scratch. Finite Element simulation show that the model is highly accurate for back-rake angles smaller than 25'. From the model, an inverse technique to predict the fracture toughness is developed and implemented. This technique is validated for scratch tests on cement paste, Jurassic limestone, red sandstone and Vosges sandstone. and applied to oil cements hydrated at high temperature and pressure. The application shows that the scratch tests is highly reproducible. almost non-destructive, and not more sophisticated than classical strength-of-materials tests; which makes this *old' technique highly attractive for both materials research and industrial applications.
by Ange-Therese Akono.
S.M.

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3

Seriacopi, Vanessa. "Evaluation of abrasive mechanisms in metallic alloys during scratch tests: a numerical-experimental study in micro-scale". Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/3/3151/tde-12032018-144239/.

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The abrasion can have some approaches, such as: (i-) the manufacturing processes and the production of different surface features and finishing of workpieces and components; and (ii-) in terms of the wear and failure, which occur in tools materials. The present thesis consists in developing a numerical model by Finite Element Method (FEM) validated by experimental tests, aiming to evaluate microstructural influences on the abrasion of metallic alloys. Therefore, objectives are related to define rules focused on ductile material design to obtain cutting resistance. Regardless of their applications, the abrasive micro-mechanism depends on mechanical and damage properties of the materials and their microstructure. A simplified abrasion study is developed considering a single abrasive over a microstructure to evaluate from ploughing to cutting. Thus, scratch tests are performed in micro-scale, applying different ranges of constant normal force. Moreover, the specimen characterization was conducted using optical and electronic microscopy techniques, optical interferometry, conventional hardness, and instrumented indentation. By the developed numerical approach, the results were: (a-) in terms of apparent coefficient of friction (COF), the found numerical and experimental mismatches are assigned to the effects of adhesion, anisotropy, grain boundaries and twinning, for instance, which were not taken into account on the modelling; (b-) the hard precipitates have a prevailing effect over the matrix regarding the apparent COF, whereas the matrix effect is dominant of the soft precipitates on the COF behavior; (c-) as a consequence of the reduced strain energy and tangential load, the local COF decreased when the abrasive scratches the hard precipitates; (d-) regarding the depth of penetration and removed volume, the numerical results are in accordance with the experimental results; (e-) there is not a remarkable micro-mechanism transition using the approach of the dimensional wear coefficient as a function of normal load, which indicates that several abrasive micro-mechanisms can occur in a single scratching; however, a predominance of a certain micro-mechanism can be observed; (f-) hard precipitates often decreases the local depth of penetration and, as a consequence, they cause the reduced of removed volume and increased the local specific energy; (g-) considering the studied range of the normal load, soft precipitates follow the matrix mass removal behavior, but these particles can show fluctuations of the local specific energy in the less severe abrasion; and, finally, (h) the map of the abrasive resistance x deformed hardness/attack angle is an important tool to point out the dominant ductile or brittle effect on the microstructure (mechanical properties); and it delineates frontiers for the abrasive micromechanisms.
A abrasão pode ser tanto tratada do ponto de vista de processos de manufatura e geração de características superficiais distintas em peças e componentes, quanto pode ser abordada em termos de desgaste e falha em diferentes ferramentas aplicadas em processos de fabricação. A presente tese remete ao desenvolvimento de um modelo numérico pelo Método dos Elementos Finitos (MEF), validado por ensaios experimentais, com o objetivo de avaliar influências de aspectos microestruturais na abrasão de ligas metálicas. Portanto, o objetivo desta tese é focado na construção de regras que auxiliem no projeto de materiais dúcteis para terem resistência ao corte. Independentemente da aplicação, os estudos da ocorrência dos micro-mecanismos de abrasão incorporam propriedades mecânicas e de dano dos materiais e suas fases. A avaliação do micro-sulcamento ao micro-corte foi realizada a partir de um estudo simplificado de abrasão, considerando o riscamento de microestruturas por um único abrasivo. Dessa forma, ensaios de riscamento em micro-escala aplicando força normal constante dentro de uma faixa específica. Em adição, as caracterizações das amostras são realizadas a partir de técnicas de microscopia óptica e eletrônica, interferometria óptica, dureza convencional e indentação instrumentada. Por meio da abordagem numérica desenvolvida, os principais resultados obtidos foram: (a-) in termos de coeficiente de atrito aparente (COF), as divergências numérica e experimental encontradas foram decorrentes principalmente do efeito da adesão, anisotropia, contornos de grão e maclação que não foram levadas em conta na simulação; (b-) os precipitados duros tendem a ter efeito predominante sobre a matriz no que diz respeito ao COF aparente, ao passo que a influência da matriz é predominante sobre o comportamento dos precipitados moles; (c-) como consequência das reduções de energia de deformação e força tangencial, o COF local tende a ser diminuído quando o abrasivo passa por precipitados duros durante o riscamento; (d-) os resultados numéricos de profundidade de penetração média e volume removido total são consistentes com os resultados experimentais; (e-) não há uma transição marcante de micro-mecanismo em função de coeficiente de desgaste dimensional em função da carga, indicando uma predominância de um certo micro-mecanismo em um dado risco e, não ocorrendo transições bruscas; (f-) precipitados duros, em geral, diminuem a profundidade de penetração local e, assim, eles reduzem o volume removido e aumentam a energia específica; (g-) para a faixa de força normal avaliada, os precipitados moles seguiram o comportamento de remoção de material de sua matriz, mas podem apresentar oscilações na energia específica local nas condições menos severas de abrasão; e, por fim, (h-) o mapa de resistência à abrasão x dureza após deformação/ângulo de ataque é uma importante ferramenta para definir efeitos dominantes de propriedades mecânicas (dúctil e frágil) na microestrutura submetida à abrasão, e faz o delineamento de fronteiras de micro-mecanismos abrasivos.

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Bernardes, Rodrigues Guilherme. "Friction anisotropy of metallic thin films deposited by Glancing Angle Deposition (GLAD) : Morphological and crystallographic aspects". Electronic Thesis or Diss., Bourgogne Franche-Comté, 2024. http://www.theses.fr/2024UBFCD065.

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Une technique prometteuse pour introduire une anisotropie de frottement dans une surface est la Glancing Angle Deposition (GLAD). Cette méthode a démontré un large éventail de possibilités pour créer des films avec diverses morphologies et caractéristiques structurelles, qui peuvent induire une anisotropie dans diverses propriétés physiques. Cependant, l'étude de l'anisotropie de frottement des films GLAD reste limitée, ce qui peut conduire à une sous-utilisation de cette technique dans les applications tribologiques. Dans ce contexte, cette thèse vise à étudier l'utilisation potentielle du GLAD pour induire une anisotropie de frottement, en se concentrant particulièrement sur l'influence des facteurs morphologiques et cristallographiques. Deux métaux, le tungstène (W) et le molybdène (Mo), ont été sélectionnés pour être déposés dans différentes conditions. Des essais de rayure ont été effectués à différentes charges normales et à différentes directions de rayage afin de déterminer si l'anisotropie de frottement pouvait être systématiquement obtenue et comment elle se manifeste. Les résultats indiquent qu'il est non seulement possible d'obtenir une anisotropie de frottement grâce au GLAD, mais aussi que différents types d'anisotropie peuvent être observés. Ce comportement anisotrope semble être principalement régi par la morphologie du film, en particulier par le contrôle de la déformation plastique et des interactions colonne-colonne. En outre, le type de matériau et l'angle de dépôt influencent considérablement l'anisotropie du frottement, les films de Mo présentant des caractéristiques anisotropes plus complexes que les films de W. Bien que l'impact significatif de la morphologie sur le comportement de la plupart des films soit évident, un film de Mo a démontré que d'autres facteurs peuvent également contribuer à des réponses de frottement atypiques
One promising technique for introducing friction anisotropy in a surface is the Glancing Angle Deposition (GLAD). This method has demonstrated a wide range of possibilities for creating films with diverse morphologies and structural characteristics, which may induce anisotropy in various physical properties. However, the study of friction anisotropy in GLAD films remains limited, potentially leading to the underutilization of this technique in tribological applications. In this context, this thesis aims to investigate the potential use of GLAD to induce friction anisotropy, with a particular focus on the influence of morphological and crystallographic factors. Two metals, tungsten (W) and molybdenum (Mo), were selected for deposition under varying conditions. Scratch tests were conducted with different normal loads and scratching directions to determine whether friction anisotropy could be consistently achieved and how it manifests. The results indicate that not only is it possible to obtain friction anisotropy through GLAD, but also that different types of anisotropy can be observed. This anisotropic behavior seems to be primarily governed by the film’s morphology, particularly through the control of plastic deformation and column-column interactions. Furthermore, the type of material and deposition angle were found to significantly influence friction anisotropy, with Mo films exhibiting more complex anisotropic characteristics than W films. Although the significant impact of morphology on the behavior of most films was evident, a Mo film demonstrated that other factors may also contribute to atypical frictional responses

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5

Damarla, Gowrisankar. "Determination of Wear in Polymers Using Multiple Scratch Test". Thesis, University of North Texas, 2004. https://digital.library.unt.edu/ark:/67531/metadc4627/.

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Wear is an important phenomenon that occurs in all the polymer applications in one form or the other. However, important links between materials properties and wear remain illusive. Thus optimization of material properties requires proper understanding of polymer properties. Studies to date have typically lacked systematic approach to all polymers and wear test developed are specific to some polymer classes. In this thesis, different classes of polymers are selected and an attempt is made to use multiple scratch test to define wear and to create a universal test procedure that can be employed to most of the polymers. In each of the materials studied, the scratch penetration depth s reaches a constant value after certain number of scratches depending upon the polymer and its properties. Variations in test parameters like load and speed are also studied in detail to understand the behavior of polymers and under different conditions. Apart from polystyrene, all the other polymers studied under multiple scratch test reached asymptotes at different scratch numbers.

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Browning, Robert Lee. "Quantitative characterization of polymer scratch behavior using a standardized scratch test". Thesis, Texas A&M University, 2003. http://hdl.handle.net/1969.1/5988.

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The lack of a widely-accepted quantitative methodology for evaluating the scratch behavior of polymeric materials has resulted in the development and establishment of a new methodology recently standardized as ASTM D7027-05. Using a custom-built instrumented scratch machine, it is possible to produce controlled, repeatable scratches on polymer surfaces under constant or linearly increasing loading conditions at constant or increasing scratch rates. Software-aided digital image analysis along with material science tools (SEM, OM, FTIR, etc.) allows polymer scratch behavior to be analyzed without the ambiguity inherent in the past. The current work will serve to describe the motivation for the development of this methodology as well as illustrate the effectiveness of the increasing load/constant rate test mode in three case studies. First, it will be shown that an acrylic coating on a steel system exhibits three zones of scratch damage: adhesive delamination, transverse cracking and finally buckling failure. It will be discussed how increases in ductility and thickness serve to improve the scratch resistantance of this coating/substrate system. Improvements in the scratch behavior of thermoplastic olefins (TPOs) through the use of surface-treated talc fillers and the slip agent erucamide will be shown in the second case. It was found that the surface-treatment of the talc likely allows for enhanced migration of the erucamide to the TPO surface, thus lowering the surface friction and greatly increasing scratch resistance. Finally, the effects of processing conditions, namely injection molding, on the scratch behavior of neat i-polypropylene will be represented by the results of scratch tests conducted where the scratch direction was oriented both along and transverse to the polymer melt flow direction. Based on the findings of the study, there appears to be a high degree of surface anisotropy introduced to injection-molded polymers due to complex fluid flow regimes as well as non-uniform cooling properties.

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Wong, Min Hao. "The development of scratch test methodology and characterization of surface damage of polypropylene". Texas A&M University, 2003. http://hdl.handle.net/1969.1/1194.

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A new scratch test methodology is proposed. The new test methodology is developed based on the principles of materials science and solid mechanics, which include the consideration of material parameters, use of microscopy for image analysis and the finite element method (FEM). The consistency and reproducibility of test results are shown using a new scratch test device on two sets of neat and talcfilled polypropylene (PP) systems. Three different test conditions, i.e., linear load increase under constant rate, constant load under constant rate, and linear rate increase under constant load, have been conducted to determine the most effective, informative test conditions for evaluation of scratch resistance of polymers. Experimental observations and FEM results show a good qualitative correlation. The unique advantages of the new scratch test method for evaluating scratch resistance of polymers are discussed. A systematic study of surface damage effected by a progressive scratching load is performed on model polypropylene (PP) systems. Mar-scratch and stress -whitening transitions can be readily observed, and the corresponding critical loads determined. Distinctive scratch hardnesses and surface damage features are found for different material systems. Visibility of scratched surface is quantified using gray level analysis via a flatbed scanner and a commercial image analysis tool. It is found that the onset of scratch visibility can be determined accurately and reproducibly using the custom -built scratcher under progressive loading condition. Talc particles are found to be responsible for the increased light scattering, leading to greatly increased visibility. The observed scratch visibility is also found to be related to the measured frictional force profiles. Approaches for producing scratch resistant PP are discussed.

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Bard, Romain (Romain M. ). "Analysis of the scratch test for cohesive-frictional materials". Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/61521.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2010.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (p. 143-148).
In this thesis we develop analytical solutions for the relations between scratch hardness and strength properties of cohesive-frictional materials of the Mohr-Coulomb and Drucker-Prager type. Based on the lower-bound yield design approach, closed form solutions are derived for frictionless scratch devices, and validated against computational upper bound and elastoplastic Finite Element solutions. The influence of friction at the blade{material interface is also investigated, for which a simple computational optimization is proposed. The model is extended to porous cohesive-frictional materials through the use of a homogenized strength criterion based on the Linear Comparison Composite theory. Relations between scratch hardness, porosity and strength properties are proposed in the form of fitted functions. Illustrated for scratch tests on cement paste, we show that the proposed solutions provide a convenient way to determine estimates of cohesion and friction parameters from scratch data, and may serve as a benchmark to identify the relevance of strength models for scratch test analysis.
by Romain Bard.
S.M.

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9

Atroshenkova, Anastasiia, e Анастасія Олександрівна Атрошенкова. "Strength properties investigation of glass by scratch test method". Thesis, National Aviation University, 2021. https://er.nau.edu.ua/handle/NAU/54160.

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Робота публікується згідно наказу Ректора НАУ від 27.05.2021 р. №311/од "Про розміщення кваліфікаційних робіт здобувачів вищої освіти в репозиторії університету". Керівник роботи: доцент, к.т.н. Закієв Вадим Ісламович
This master thesis is dedicated to the сomparative study of glass strength using scratch test technique. The methods of investigation are scratch tests, nanoindentation and calculation methods for results analysis.
Ця магістерська робота присвячена порівняльному вивченню міцності скла за допомогою методики випробування дряпанням. Методами дослідження є скретч-тести, наноіндентування та розрахункові методи аналізу результатів.

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Dyrda, Katia Marjolaine. "Adhesion characterization of hard ceramic coatings by the scratch test". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ37948.pdf.

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Più fonti

Libri sul tema "Scratch tests"

1

E, Sliney Harold, Deadmore Daniel L e Lewis Research Center, a cura di. Screen cage ion plating (SCIP) and scratch testing of polycrystaline aluminum oxide. [Cleveland, Ohio]: National Aeronautics and Space Administration, Lewis Research Center, 1992.

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2

E, Sliney Harold, Deadmore Daniel L e Lewis Research Center, a cura di. Screen cage ion plating (SCIP) and scratch testing of polycrystaline aluminum oxide. [Cleveland, Ohio]: National Aeronautics and Space Administration, Lewis Research Center, 1992.

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3

Edge, M. D. Statistical Thinking from Scratch. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780198827627.001.0001.

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In virtually every field, researchers find themselves navigating tremendous amounts of new data. Making sense of this flood of information requires much more than the rote application of traditional statistical methods. This book will train researchers to be creative and confident users of statistics by thinking hard about the application of simple methods to a small dataset. In particular, this book focuses on simple linear regression—a method with strong connections to the most important tools in applied statistics—using it as a detailed case study for teaching resampling-based, likelihood-based, and Bayesian approaches to statistical inference. This exercise imparts an idea of how statistical procedures are designed and implemented, a flavor for the philosophical positions one implicitly assumes when applying statistics, and an opportunity to probe the strengths and weaknesses of one’s statistical approach. Key to the book’s novel approach is its mathematical level, which is gentler than most texts for statisticians but more rigorous than most introductory texts for non-statisticians. Statistical Thinking from Scratch is suitable for senior undergraduate and beginning graduate students, professional researchers, and practitioners seeking to improve their understanding of statistical methods across the natural and social sciences, medicine, psychology, public health, business, and other fields.

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Dutch, Jennifer Rachel. Look Who's Cooking. University Press of Mississippi, 2018. http://dx.doi.org/10.14325/mississippi/9781496818751.001.0001.

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In twenty-first century America, Home cooking has transformed from an overwhelming chore to a nearly avoidable pastime. This rapid disappearance of kitchen skills has led critics to lament the death of home cooking. “No one cooks anymore” is a rallying cry to get Americans back to cooking from scratch in order to improve health and increase happiness. However, this mourning for home cooking only serves to underscore its significance as a symbol of the importance of food to family, home, and community, which comes through in the rhetoric found in a variety of texts, including cookbooks, advertising, and YouTube videos. Analysis of these texts reveals that, far from dying, home cooking traditions continue as a powerful form of folklore that American fill with meaning as a representation of both the continuity of the past and the possibilities of the future.

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Wright, Jonathan, e Dawson Barrett. Punks in Peoria. University of Illinois Press, 2021. http://dx.doi.org/10.5622/illinois/9780252043802.001.0001.

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Peoria, Illinois has long been a benchmark for the cautious and the conservative, a popular American test market for ideas, entertainment acts, and products. Beginning in the 1980s, hardcore punk rock bands “played in Peoria,” right alongside Reagan Republicanism and a series of factory closings. Spanning two decades and many waves of youth, this book explores how various misfits and outcasts repurposed elements of their deindustrializing city to promote local and touring bands, build social networks, and grapple with the possibilities and shortcomings of subcultural and countercultural politics. The vast majority of books about subcultures, and punk rock in particular, focus on bands, music scenes, and youth in vibrant, world-class metropolitan areas such as London, New York, and Los Angeles. In contrast, this book examines the efforts of young people to create an alternative music scene, from scratch, in Peoria – a typical, conservative, mid-sized city in the American Midwest.

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Capitoli di libri sul tema "Scratch tests"

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Konin, Jeff G., Denise Lebsack, Alison R. Snyder Valier, Jerome A. “Jai” Isear e Holly Brader Marakovits. "Apley's Scratch Test". In Special Tests for Orthopedic Examination, 36–38. 4^a ed. Boca Raton: CRC Press, 2024. http://dx.doi.org/10.1201/9781003526490-19.

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Lilleaas, August. "Automated Tests with jUnit 5". In Pro Kotlin Web Apps from Scratch, 119–39. Berkeley, CA: Apress, 2023. http://dx.doi.org/10.1007/978-1-4842-9057-6_7.

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Denkena, Berend, Luis de Leon, Marijke van der Meer e Analía Moral. "Scratch Tests on Natural Nacre - Reference for Implant Material". In Friction, Wear and Wear Protection, 227–33. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2011. http://dx.doi.org/10.1002/9783527628513.ch27.

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Karimzadeh, A., e M. R. Ayatollahi. "Mechanical Properties of Biomaterials Determined by Nano-Indentation and Nano-Scratch Tests". In Solid Mechanics and Its Applications, 189–207. Dordrecht: Springer Netherlands, 2013. http://dx.doi.org/10.1007/978-94-007-6919-9_10.

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Gitis, Norm V., Suresh Kuiry, Ilja Hermann e Jun Xiao. "Nano and Micro Indentation and Scratch Tests of Mechanical Properties of Thin Films". In Advanced Tribology, 489–90. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-03653-8_152.

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Kästner, F., e K. M. de Payrebrune. "Physical Modeling of Grinding Forces". In Proceedings of the 3rd Conference on Physical Modeling for Virtual Manufacturing Systems and Processes, 70–89. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-35779-4_5.

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AbstractIn order to address the increasing demands on precision in manufacturing, the prediction of various processes by model-based methods is increasingly becoming a key technology. With respect to this, the grinding process still reveals a lot of potential in terms of reliable predictions. In order to exploit this potential and to improve the understanding of the process itself, a physical force model is developed. Here, process-typical influencing factors, as well as commonly used cooling lubricants, are considered. In addition to the simulative effort for the actual model, basic experimental investigations have to be carried out. In single scratch tests, it has been found that process and deformation mechanisms such as rubbing, ploughing, and cutting of the material and also the pile-up of this material on both sides of the cutting grain are significantly involved in the development of forces. It also turned out that the resulting forces are greater when cooling lubricants are used and that the topographic characteristics of a scratch are also affected by them. For a realistic mapping of these effects within the force model, the deformation model, according to Johnson and Cook, and a discretization, according to Arbitrary Lagrangian-Eulerian, proved most suitable. For integrating the cooling lubricants, the Reynolds equation using a subroutine proves to be a suitable instrument. The challenge to complete the force model is combining the scratch and the Reynolds equation simulation.

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Singh, Jitendra Kumar, U. S. Rao e Ram Pyare. "Study of Traction Forces at Elevated Temperatures During Micro-Scratch Tests on 45S5 Bioglass". In Lecture Notes in Mechanical Engineering, 565–75. Singapore: Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-19-7709-1_57.

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Müller, Tobias, Daisy Nestler, Thomas Lampke e Bernhard Wielage. "Numerical Simulation of Scratch Tests for the Verification of Material Models for Particle-Reinforced Coatings". In Integration of Practice-Oriented Knowledge Technology: Trends and Prospectives, 323–31. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-34471-8_26.

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Gallego, Antolino, Jose F. Gil, J. M. Vico, Enrique Díaz Barriga-Castro, J. E. Ruzzante e Rosa Piotrkowski. "Wavelet Transform and Bispectrum Applied to Acoustic Emission Signals from Adherence Scratch-Tests on Corroded Galvanized Coatings". In Advanced Materials Research, 83–88. Stafa: Trans Tech Publications Ltd., 2006. http://dx.doi.org/10.4028/0-87849-420-0.83.

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Lee, Da-Jeong, Seung-Won Seo, Hyung-JunYoon, Hye-Lee Kim, Jung-Suk Han e Dae-Joon Kim. "Application of Scratch Hardness Tests for Evaluation of Partially-Sintered Zirconia CAD/CAM Blocks for All-Ceramic Prosthesis". In Ceramic Transactions Series, 149–53. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2014. http://dx.doi.org/10.1002/9781118771587.ch14.

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Atti di convegni sul tema "Scratch tests"

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Dutt, Shreya. "Detecting Food Allergies Through Scratch Testing and Blood Tests". In 2024 IEEE Integrated STEM Education Conference (ISEC), 1. IEEE, 2024. http://dx.doi.org/10.1109/isec61299.2024.10665292.

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Mercier, Christian, e Alexandre Gierczynski. "HCE Kerosene Piston Engine Light Helicopter Demonstrator Results". In Vertical Flight Society 73rd Annual Forum & Technology Display, 1–8. The Vertical Flight Society, 2017. http://dx.doi.org/10.4050/f-0073-2017-12143.

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In the frame of GRC4, part of Cleansky's Green Rotorcraft Integrated Technology Demonstrator (ITD), Airbus Helicopters has led the development of a flying demonstrator based on the H120 serial helicopter and fitted with a designed from scratch reciprocating engine running on kerosene and named HCE for High-Compression Engine. On this research project Airbus Helicopters teamed with TEOS Powertrain Engineering, France, and AustroEngine GmbH, Austria, regrouped in the Consortium HIPE 440. Engine bench tests started in March 2013. Ground tests were completed in March 2015. With a Maiden Flight on November 6th 2015, the flight test campaign is to last until the end of 2017. This paper explains the specifics of the High Compression Engine, which triggered the need to build the new engine from scratch. It more particularly presents the achievements of the research project in terms of engine mass-to-power ratio, power output, fuel consumption, torque oscillations, engine displacements, rotor speed control and cooling system, which achievements where revealed during flight tests carried with up to 32°C OAT (ISA+17°C).

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Kus, Adrian, Sascha Schneider, Martin Hollands, Raphael Rammer, Oliver Dieterich e Martijn Priems. "GRC1: An Advanced Five-Bladed Bearingless Main Rotor Dynamics and Acoustics from Draft to Flight Test". In Vertical Flight Society 74th Annual Forum & Technology Display, 1–13. The Vertical Flight Society, 2018. http://dx.doi.org/10.4050/f-0074-2018-12754.

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Funded by the European research program Clean Sky Green Rotorcraft (GRC), a new five-bladed bearingless main rotor demonstrator has been developed and tested between 2014 and 2016 at Airbus Helicopters, hereafter denoted as GRC1 rotor. While inheriting rotor controls, control cuff, flexbeam and lead-lag damper from the Bluecopter™ main rotor, the rotor blade itself was developed from scratch within the research project. Main target was to achieve an ecofriendly design by simultaneously reducing acoustic signature, fuel consumption and vibratory loads while optimizing manufacturing costs. This could be achieved by proper balancing the requirements of the technical disciplines acoustics, aerodynamics, dynamics, loads, performance and handling qualities. While these targets have been achieved, demonstrated by ground and flight tests, excellent agreement between numerical predictions and test results was achieved. This paper provides an overview on the aeromechanics, acoustics and performance aspects after summarizing the evolution of bearingless main rotors at Airbus Helicopters.

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Marple, B. R., H. M. Hawthorne e Y. Xie. "Characterization of Nanostructured and Conventional Cermet Coatings by Controlled Scratch Testing: Correlation with Abrasion and Hardness Tests". In ITSC2004, a cura di Basil R. Marple e Christian Moreau. ASM International, 2004. http://dx.doi.org/10.31399/asm.cp.itsc2004p0846.

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Abstract Controlled scratch testing, dry abrasion tests and hardness measurements were performed on WC-12Co coatings produced by the high velocity oxy-fuel spraying of nanostructured and conventional feedstock powders. The information obtained employing these different evaluation techniques was used to provide insight into coating behaviour and identify the most abrasion-resistant coatings. The results indicated a correlation between scratch hardness and the microhardness determined by Vickers indentation for the coatings. There was good agreement between the scratch test and the abrasion test in identifying the best coatings for use in dry abrasion. Observation of the scratched surfaces and wear scars indicated material removal by splat debonding and fracture. The results demonstrate the usefulness of the scratch test for assessing the abrasion resistance and wear behaviour of coatings.

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Sikora, Janusz, e Daniel Pieniak. "TESTS OF SCRATCH RESISTANCE OF POLYMER MATERIAL SURFACES". In 14th International Conference on Evolutionary and Deterministic Methods for Design, Optimization and Control. Athens: Institute of Structural Analysis and Antiseismic Research National Technical University of Athens, 2021. http://dx.doi.org/10.7712/140121.7966.18360.

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Byon, Eungsun, Soo-Wohn Lee, Junya Kitamura e Kenneth Holmberg. "Adhesion/Cohesion Strength of Plasma Sprayed Ceramic Coatings by Scratch Testing On Cross-Section". In ITSC2013, a cura di R. S. Lima, A. Agarwal, M. M. Hyland, Y. C. Lau, G. Mauer, A. McDonald e F. L. Toma. ASM International, 2013. http://dx.doi.org/10.31399/asm.cp.itsc2013p0516.

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Abstract This work investigates the reliability and reproducibility of scratch testing for YSZ and TiO2 coatings deposited on NiCr bondcoats by plasma spraying. Scratch tests were conducted on cross-sections of the spray coatings. An image of the scratched area was taken after testing using an optical microscope in order to determine failure mode. With a statistical evaluation, the adhesion and cohesion strength were determined. The results show that cross-sectional scratch testing is effective for estimating the adhesion and cohesion strength of plasma spray coatings.

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Ovaert, Timothy C., e B. R. Kim. "Estimation of Polymer Coating Scratch Tensile Strength by Nano-Indentation, Micro-Scratch Testing, and Finite Element Modeling". In World Tribology Congress III. ASMEDC, 2005. http://dx.doi.org/10.1115/wtc2005-63700.

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In a previous paper, polymer coating viscoelastic/plastic properties were determined using nanoindentation and the finite element method. In this work, the individual layers, once characterized, were assembled into a multi-layered structure and subject to micro-scratch tests. These tests determined a critical scratch indentation load for the layered structure, as designated by the first appearance during scratching of visible surface layer tensile cracks. Scratch tests were carried out for three different conical scratch tip radii. The top-layer tensile strength of the layered structures was then estimated, utilizing the individual layer properties, the top layer friction coefficients, the micro-scratch test critical loads, and a finite element scratch model, for each scratch tip radius. The values of the top layer scratch tensile strengths were in good agreement for each of the three tip radii, as anticipated. The top-layer scratch tensile strengths may be utilized for further analysis and comparison of differences in gloss retention after gloss reduction experiments. The method may be used as a basis for coating selection, comparison, and performance testing in scratch-resistant polymer coating applications.

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Mohammadi, Hossein, e John A. Patten. "Scratch Tests on Granite Using Micro-Laser Assisted Machining Technique". In ASME 2015 International Manufacturing Science and Engineering Conference. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/msec2015-9327.

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In this study, micro-laser assisted machining (μ-LAM) technique is used to perform scratch test on a granite sample. Rocks are generally considered as brittle materials with poor machinability and severe fracture can be resulted when trying to cut them due to their low fracture toughness. Due to increasing demand for these materials in industry with many applications, finding a fast and cost effective process with higher product quality seems essential. In past research in our research group, it has been demonstrated that machining of brittle materials such as semiconductors and ceramics in ductile regime is possible due to the high pressure phase transformation (HPPT) occurring in the material caused by the high compressive and shear stresses induced by a single point diamond tool tip. Scratch tests were performed on the granite sample and to further augment the process, traditional cutting is coupled with the laser to soften the material and get the higher depth of cut. In this research, results of scratch tests done on granite, with and without laser heating have been compared. The effect of laser heating was studied by verifying the depths of cuts for scratch tests with varying the laser power during the process. Microscopic images and three-dimensional profiles of cuts taken by using a white light interferometer were investigated. Results show that using laser can increase depth of cut and with 15 W laser power it is increased — for different regions of granite sample — from 25% to 95%.

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Valeeva, Irina, e Ivan Goroshko. "Finite element analysis of scratch test of films on substrate". In IXth INTERNATIONAL SAMSONOV CONFERENCE “MATERIALS SCIENCE OF REFRACTORY COMPOUNDS”. Frantsevich Ukrainian Materials Research Society, 2024. http://dx.doi.org/10.62564/m4-iv1352.

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Scratch test is an important investigation method which is used to evaluate mechanical properties of materials and structures, adhesion of coatings, etc. The stress distribution in the sample is the most important information, which affects its deformation, damage and fracture of the sample material. Simulation of scratch tests of samples with refractory, hard and other coatings or different film-substrate systems allows us to understand which type of load occurs between the substrate and the coating, which type of load affects delamination of coatings [1]. The aim of this study is to implement finite element simulation of the elasto-plastic deformation during scratch test using ANSYS software. The scratch tests were performed to study the adhesive properties of films on substrates. The test was performed with a linearly increasing force of 13 mN/s applied vertically to the indenter. The force was increased until the load reached 500 mN. At the same time, the Rockwell indenter was moved at a speed of 10 μm/s in the horizontal direction. The radius of the Rockwell indenter was 10µm. Finite element analysis of scratch test was applied to film-substrate systems. Large deformation in scratch zone causes essential difficulties during finite element analysis that related to mesh distortion, which leads to an abort of solution process. To overcome these computational difficulties, researchers use special approaches and software. Nonlinear mesh adaptive technology was applied to overcome the distortion of finite elements. The fields of displacement, stress, and strain in the film-substrate systems were obtained as a result of scratch test simulation. Numerical simulation allows us to study the influence of each parameter on the scratch test results. Finite element analysis can explain how the results of scratch test depend on the mechanical properties of the film-substrate systems.

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Menezes, Pradeep L., Kishore e Satish V. Kailas. "Effect of Directionality of Grinding Marks on Friction at Different Surface Roughness Using Inclined Scratch Test". In World Tribology Congress III. ASMEDC, 2005. http://dx.doi.org/10.1115/wtc2005-64000.

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Surface topography of a tool plays an important role as it predominantly controls the frictional behavior at the interface. In the present study, Inclined Scratch Tester was used to understand the effect of directionality of surface grinding marks on coefficient of friction and transfer layer formation. EN8 steel flats were ground to attain different surface roughness with unidirectional grinding marks. Then Al-Mg alloy pins were scratched against the prepared EN8 steel flats. Grinding angle (angle between direction of scratch and grinding marks) was varied between 0° and 90° during the scratch tests. It was observed that the coefficient of friction and transfer layer formation depend primarily on the directionality of grinding marks of the harder mating surface, and independent of surface roughness of harder mating surface. The grinding angle effect on coefficient of friction was attributed to the variation of plowing component of friction with grinding angle.

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Rapporti di organizzazioni sul tema "Scratch tests"

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Alizadeh, Philipp, Kevin Oberle e Rainer Dahlmann. Process transfer of PECVD gas barrier coatings between PE-HD and PP hollow bodies. Universidad de los Andes, dicembre 2024. https://doi.org/10.51573/andes.pps39.gs.nn.2.

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This study investigates the plasma enhanced chemical vapor deposition (PECVD) coating process transfer between PE and PP substrates. An inverse relationship is observed between the barrier improvement factor (BIF) and applied energy density (E), with PE showing a stronger response. The same process gas ratio optimizes both materials, suggesting geometry influences the barrier effect more than material. However, the barrier on PP is limited, indicating poorer compatibility to functionalization. The development of the intermediate layer did not improve the barrier performance. FESEM analyses and scratch tests suggest material damage during coating application. Further research is needed to optimize the coating process.

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Lim, Hannah, John Curry e Michael Dugger. Improved Throughput and Analysis of Scratch Test Results via Automation and Machine Learning. Office of Scientific and Technical Information (OSTI), febbraio 2022. http://dx.doi.org/10.2172/1861003.

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Wongkasemjit, Sujitra. Comparison of titanium dioxide/silicon dioxide/zirconium dioxide synthesized via sol-gel process to be used as lens protection : final report. Chulalongkorn University, 2004. https://doi.org/10.58837/chula.res.2004.97.

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Many hard coating materials have been developed and based on the use of metal alkoxide or organosiloxanes prepared via the sol-gel process. Titanium glycolate, zirconium glycolate and silatrane precursors were processed as hard coating materials for polyurethane lens. These precursors are inexpensive and the preparation reaction is simple and straightforward. The effects of the sol-gel process parameters, viz, the type of precursors, the coupling agent (GPTS), and the curing agent (3-APS) were investigated. The surface property evaluation of ophthalmic lens was conducted with respect to the scratch resistance, the adhesion by the tape test, the immersion in boiling water, the refractive index, the %light transmission. The coating solutions were applied onto the polyurethane substrate to achieve the film thickness of ~5.0 m, at the optimized concentration. Silatrane has a good property using the formula of precursor:HCI:IPA:GPTS:%APS(by volume) equal to 0.05g:600 L:1000 L:5%. The same condition was applied for the zirconium glycolate precursor. On the other hand, the titanium glycolate precursor was found to have the optimal formula of 0.05g:600 L:1000 L:600 L:4%. The scratch line results at the coated polyurethane are superior when compared with that of the uncoated polyurethane. When compared with the commercially hard coating lens, the results are nearly the same.

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Pinkus, Alan R., e Martha A. Hausmann. Interlaboratory Study (ILS) For F 428-83, The Standard Test Method for Intensity of Scratches on Aerospace Glass Enclosures. Fort Belvoir, VA: Defense Technical Information Center, gennaio 2003. http://dx.doi.org/10.21236/ada416229.

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Pinkus, Alan R., e Martha A. Hausmann. Interlaboratory Study (ILS) for F 548-01, The Standard Test Method for Intensity of Scratches on Aerospace Transparent Plastics. Fort Belvoir, VA: Defense Technical Information Center, gennaio 2003. http://dx.doi.org/10.21236/ada416273.

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Turner, Nigel E., Nicolas Trajtenberg, Steve Cook, Olga Sanchez de Ribera, Jing Shi e Henrietta Bowden-Jones. A health inequality examination of problem gambling, substance abuse, mental health, and poverty in the United Kingdom; A secondary analysis and stakeholder interviews. Greo Evidence Insights, 2023. https://doi.org/10.33684/2024.003.

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Purpose: This project is focused on the social determinants of health associated with problem gambling and examined gambling-related disparities and the determinants of negative health outcomes. Social determinants include social class education, ethnic group, age, and sex (Elton-Marshall, et al., 2017). The main aims of the study were as follows: Aim 1: In this study, we used the large data set to determine subpopulations who are experiencing social inequity (e.g., youth, older adults, women, Black people and other minority ethnic groups, and people with low income; see Elton-Marshall, et al., 2017) to determine how much they are impacted by gambling. Aim 2: We tested the data as an interaction model to see if there are disparities in the impact of gambling by sociodemographic variables. The analysis included tests of the factorial structure of the Problem Gambling Severity Index (PGSI) across subpopulations (e.g., young vs. old, low-income vs. higher income, and Scotland vs England). Aim 3: In addition, we conducted interviews with a small number of key stakeholders who were treatment providers or administrators of problem gambling services to discuss the research findings and to help us understand the data and develop a dissemination plan. Methodology: This project consisted of a secondary analysis of the “Gambling in England and Scotland, 2016: Combined Data from the Health Survey for England and the Scottish Health Survey.” We concatenated the data from 2012, 2014, and 2016. This study is a secondary analysis of a large data set. The project incorporated a series of statistical analysis including logistic regression, multinominal regression, cluster analysis and confirmatory factor analysis and to explore the relationship between gambling and social and demographic variables. Results: Based on our analysis combining the DSM and PGSI, about half a percent of the adults in England and Scotland met the threshold for a severe gambling problem. In terms of gambling behaviors, the most common games were national lottery tickets, scratch cards, and other lotteries. As expected, social and demographic variables were both significantly associated with problem gambling. Significant social and demographic risk factors for problem gambling include sex (male), age (being younger, 25 to 34), marital status (being single or never married), social class (manual and routine labour), ethnic /racial group (Black or other), and education (lower levels of education). In addition, being a heavy drinker, a current smoker and having a lower level of Wellbeing were also related to problem gambling. Although the results suggest that people in Scotland gamble somewhat more often especially on lotteries, Country (England vs. Scotland) was not associated with gambling problems. In terms of games played, according to the logistic regression, the largest association was for electronic gambling machines (EGMs), followed by Sports gambling and then online gambling. The interaction of games with sex is interesting suggesting that the male vs. female differences is smaller for EGMs and online gambling, but larger for sports gambling. As Part of Aim 2, we tested the psychometric properties of the PGSI gambling inventory and found that the PGSI was a valid construct for measuring problem gambling in the United Kingdom (UK). Moreover, we found that the PGSI scale operated similarly for respondents from both England and Scotland, suggesting generalisability across the UK. In terms of Aim 3, the key stakeholder interviews, most of the stakeholders felt that the reported frequencies were lower than they expected and questioned the accuracy of the prevalence estimates. Several stakeholders noted that some ethnic communities (Chinese, Muslims) were not adequately represented in the survey, and speculated that this was due to under reporting. Several stakeholders also suggested that the prevalence of gambling problems among women who gamble may be higher than males who gamble, however analysis did not support this view. In terms of directions for future research, the stakeholders suggested the need to better understand the impact of trauma on gambling, the potential side effects of medication(s), and a more comprehensive examination of environmental factors during childhood that increase the risk of problem gambling during adulthood. Overall, the stakeholders felt that the results provide useful information but note that more research is needed to better understand gambling problems. Finally, several stakeholders believed that both government and industry should do more to help reduce problem gambling; however, one stakeholder cautioned that over regulation could backfire and push gamblers to non-regulated gambling sites. Conclusions: The results of this research provide a detailed examination of the association between problem gambling and the social determinants of health in the UK. In summary, the key findings are that social and demographic risk factors for problem gambling include sex (male), age (being younger, 25 to 34), marital status (being single or never married), social class (manual and routine labour), ethnic /racial group (Black or other), education (lower levels of education), are significant factors in determining problem gambling. In addition, being a heavy drinker, a current smoker and having a lower level of Wellbeing, more psychological distress, and a greater rate of mental health problems, were also related to problem gambling. This knowledge will help to inform public health strategies in the UK related to the prevention and treatment of gambling disorders, as well as the prevention of gambling-related harm at the population level and for different groups (e.g., age groups, income groups, ethnic groups). Implications: 1. Problem gamblers are more likely to have lower levels of education, were less likely to be in managerial work, and in terms of ethnic group were Black or other. 2. Problem gamblers are physically healthy, but have an elevated risk of mental health problems, have a poorer sense of well-being and are more likely to smoke or engage in heavy drinking. 3. The results found that country (England vs. Scotland) was not associated with differences in gambling problems, however, people in Scotland gamble somewhat more often especially on Lotteries. 4. In terms of Aim 2, the results suggest that the PGSI is a valid measure of gambling in the Great Britain and that it is equally valid for both England and Scotland. 5. Non-problem gamblers appear to be a relatively healthy population and had the best scores in terms of mental health and well-being, though the contrasts with non-gamblers were trivial. 6. Non-problem gamblers had a somewhat greater rate of smoking, heavy drinking and obesity compared to non-gamblers suggesting they may have more health problems eventually. Effort should be made to encourage more physical activity amongst recreational gamblers.

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