Influencia de las condiciones de esmerilado sobre la aparición de capa blanca en rieles tipo R400HT para uso en el Metro de Medellín
ilustraciones, fotografías
- Autores:
-
Hernández Álvarez, Luis Guillermo
- Tipo de recurso:
- Fecha de publicación:
- 2023
- Institución:
- Universidad Nacional de Colombia
- Repositorio:
- Universidad Nacional de Colombia
- Idioma:
- spa
- OAI Identifier:
- oai:repositorio.unal.edu.co:unal/86016
- Palabra clave:
- 380 - Comercio , comunicaciones, transporte::385 - Transporte ferroviario
620 - Ingeniería y operaciones afines::625 - Ingeniería de ferrocarriles y de carretera
Metro (Sistema de transporte) - Medellín (Colombia)
Transporte ferroviario - Medellín (Colombia)
Rieles - Esmerilado
Metro (Sistema de transporte) - Mantenimiento y reparación
Fatiga de materiales
Resistencia de materiales
Esmerilado de rieles
Capa blanca
Fatiga por contacto de rodadura
Ensayos disco-disco
Agrietamiento
Rail grinding
Twin-disc tests
White Etching Layer (WEL)
Rolling contact fatigue
cracking
- Rights
- openAccess
- License
- Atribución-NoComercial-SinDerivadas 4.0 Internacional
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| dc.title.spa.fl_str_mv |
Influencia de las condiciones de esmerilado sobre la aparición de capa blanca en rieles tipo R400HT para uso en el Metro de Medellín |
| dc.title.translated.eng.fl_str_mv |
Influence of grinding conditions on the formation of the white layer in R400HT rails for use in the Metro de Medellín |
| title |
Influencia de las condiciones de esmerilado sobre la aparición de capa blanca en rieles tipo R400HT para uso en el Metro de Medellín |
| spellingShingle |
Influencia de las condiciones de esmerilado sobre la aparición de capa blanca en rieles tipo R400HT para uso en el Metro de Medellín 380 - Comercio , comunicaciones, transporte::385 - Transporte ferroviario 620 - Ingeniería y operaciones afines::625 - Ingeniería de ferrocarriles y de carretera Metro (Sistema de transporte) - Medellín (Colombia) Transporte ferroviario - Medellín (Colombia) Rieles - Esmerilado Metro (Sistema de transporte) - Mantenimiento y reparación Fatiga de materiales Resistencia de materiales Esmerilado de rieles Capa blanca Fatiga por contacto de rodadura Ensayos disco-disco Agrietamiento Rail grinding Twin-disc tests White Etching Layer (WEL) Rolling contact fatigue cracking |
| title_short |
Influencia de las condiciones de esmerilado sobre la aparición de capa blanca en rieles tipo R400HT para uso en el Metro de Medellín |
| title_full |
Influencia de las condiciones de esmerilado sobre la aparición de capa blanca en rieles tipo R400HT para uso en el Metro de Medellín |
| title_fullStr |
Influencia de las condiciones de esmerilado sobre la aparición de capa blanca en rieles tipo R400HT para uso en el Metro de Medellín |
| title_full_unstemmed |
Influencia de las condiciones de esmerilado sobre la aparición de capa blanca en rieles tipo R400HT para uso en el Metro de Medellín |
| title_sort |
Influencia de las condiciones de esmerilado sobre la aparición de capa blanca en rieles tipo R400HT para uso en el Metro de Medellín |
| dc.creator.fl_str_mv |
Hernández Álvarez, Luis Guillermo |
| dc.contributor.advisor.none.fl_str_mv |
Toro, Alejandro Santa Marín, Juan Felipe |
| dc.contributor.author.none.fl_str_mv |
Hernández Álvarez, Luis Guillermo |
| dc.contributor.researchgroup.spa.fl_str_mv |
Grupo de Tribología y Superficies |
| dc.subject.ddc.spa.fl_str_mv |
380 - Comercio , comunicaciones, transporte::385 - Transporte ferroviario 620 - Ingeniería y operaciones afines::625 - Ingeniería de ferrocarriles y de carretera |
| topic |
380 - Comercio , comunicaciones, transporte::385 - Transporte ferroviario 620 - Ingeniería y operaciones afines::625 - Ingeniería de ferrocarriles y de carretera Metro (Sistema de transporte) - Medellín (Colombia) Transporte ferroviario - Medellín (Colombia) Rieles - Esmerilado Metro (Sistema de transporte) - Mantenimiento y reparación Fatiga de materiales Resistencia de materiales Esmerilado de rieles Capa blanca Fatiga por contacto de rodadura Ensayos disco-disco Agrietamiento Rail grinding Twin-disc tests White Etching Layer (WEL) Rolling contact fatigue cracking |
| dc.subject.lemb.none.fl_str_mv |
Metro (Sistema de transporte) - Medellín (Colombia) Transporte ferroviario - Medellín (Colombia) Rieles - Esmerilado Metro (Sistema de transporte) - Mantenimiento y reparación Fatiga de materiales Resistencia de materiales |
| dc.subject.proposal.spa.fl_str_mv |
Esmerilado de rieles Capa blanca Fatiga por contacto de rodadura Ensayos disco-disco Agrietamiento |
| dc.subject.proposal.fra.fl_str_mv |
Rail grinding Twin-disc tests |
| dc.subject.proposal.eng.fl_str_mv |
White Etching Layer (WEL) Rolling contact fatigue cracking |
| description |
ilustraciones, fotografías |
| publishDate |
2023 |
| dc.date.issued.none.fl_str_mv |
2023-12-08 |
| dc.date.accessioned.none.fl_str_mv |
2024-05-02T19:07:32Z |
| dc.date.available.none.fl_str_mv |
2024-05-02T19:07:32Z |
| dc.type.spa.fl_str_mv |
Trabajo de grado - Maestría |
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info:eu-repo/semantics/masterThesis |
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info:eu-repo/semantics/acceptedVersion |
| dc.type.content.spa.fl_str_mv |
Text |
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http://purl.org/redcol/resource_type/TM |
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acceptedVersion |
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https://repositorio.unal.edu.co/handle/unal/86016 |
| dc.identifier.instname.spa.fl_str_mv |
Universidad Nacional de Colombia |
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Repositorio Institucional Universidad Nacional de Colombia |
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https://repositorio.unal.edu.co/ |
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Universidad Nacional de Colombia Repositorio Institucional Universidad Nacional de Colombia |
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spa |
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LaReferencia |
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C.R Ferguson, A.T Kirkpatrick, Motores de combustión interna (2 ª ed.) John Wiley, Nueva York (2001). W. Jamison, Wear of steel in combined rolling and sliding, ASLE Trans., 25 (1) (1980), pp 71-78. W.K. Chen, Linear Networks and Systems (Book style). Belmont, CA: Wadsworth, 1993, pp. 123–135. V. Reddy, G. Chattopadhyay, P.O. Larsson, D. J. Hargreaves, Modelling and analysis of Rail mantenance cost. Production Economics, 105 (2007), pp 475-482. A. Valencia, J.L. Rendón, El problema del desgaste ondulatorio en las vías férreas: la metalurgia de un caso real, Dyna 144 (2004) 29-38. F.J. Franklin, G.J. Weeda, A. Kapoor, E.J.M. Hiensch, Rolling contact fatigue and wear behaviour of the infrastar two-material rail, Wear vol 258, pag 10481054, 2005. V. Reddy, G. Chattopadhyay, P.O. Larsson-Kraik, and T. Allahmanli, Evaluation of technical vs economic decisions in rail grinding. 2008 IEEE International Conference on Industrial Engineering and Engineering Management, 2008, pp. 496–500. A. Zarembski. The art and science of rail grinding. Simmons-Boardman Bokks, Inc. 2005. P. A. Cuervo. Análisis experimental del efecto del proceso de reperfilado sobre el desgaste y fatiga por contacto de rodadura de riel en el sistema rueda-riel en el Metro de Medellín, Trabajo de Grado. Universidad Nacional de Colombia, Medellín 2014. D. Zapata, J.F. Santa, J. Sanchez, J. Gonzalez, A .Toro, Effect of Rail Grinding Conditions on Sub-Surface. Microstructure and Surface Roughness of Fatigued Rails. 1st. International Brazilian Conference on TribologyTriboBr-2010, Rio de Janeiro, Brasil. November 2010. M. Steenbergen. Rolling contacts fatigue in relation to rail grinding, Wear 356-357, 2016, pp. 110-121. http://dx.doi.org/10.1016/j.wear.2016.03.015. A. Al-Juboori, H. Zhu, D. Wexler, H. Li, C. Lu, A. McCusker, J. McLeod, S. Pannila. Characterization of White Etching Layers formed on rails subjected to different traffic conditions, Wear 436-437, 2019. S. Zakharov. Wheel/Rail Performance. En Guidelines to Best Practice for Heavy Haul Railway Operations: Wheel and Rail Interface Issues (págs. 1-86). Virginia Beach, Virginia, USA: International Heavy Haul Association, 2001. Venzario (2009), Mantenimiento ferroviario. Amolado de carriles, https://venzario.wordpress.com/2009/11/13/mantenimiento-ferroviario-amolado-de-carriles/ (Revisado Diceimbre 8, 2023) W. J. Harris Jr, W. Ebersöhn, J. Lundgren, H. Tournay, y S. Zakharov, Guidelines to Best Practices for Heavy Haul Railway Operations: Wheel and Rail Interface Issues, First Edition. International Heavy Haul Association (IHHA), 2001. The Railway Educational Bureau. The Basics of Railroad Wheels and Wheel Inspection (3rd Edition ed.). Omaha, Nebraska, United States of America, 2013. A. Kapoor, F.J. Franklin. Tribological layers and the wear of ductile materials. Wear 245. 204–215, 2000 M. Schargott, V.L. Popov, A.I. Dmitriev, S.G. Psakhie. Development of surface topography for the rail–wheel contact. Wear, 2008. J.W. Ringsberg, M. Loo-Morrey, B.L. Josefson, A. Kapoor, J.H. Beynon. Prediction of fatigue crack initiation for rolling contact fatigue. International Journal of Fatigue, Ed.22, p.205-215, 2000. R. Lewis y U. Olofsson. Wheel-rail interface handbook, 1.a ed. Boca Raton; Oxford: CRC Press ; Woodhead Pub, 2009. X.S. Jin, W.H. Zhang, J. Zeng, Z.R. Zhou, Q.Y. Liu, Z.F. Wen. Adhesion experiment on a wheel/rail system and its numerical analysis. Proc Inst Mech Eng Part J J Eng Tribol;218:293–303, 2004. Y. Areiza. Efecto de la fuerza de fricción en el contacto rueda-riel sobre el consumo medio de energía en operación del Metro de Medellín, Tesis de Maestría en ingeniería – materiales y procesos, Facultad de Minas, Universidad Nacional de Colombia, 2014. H. Harrison. The development of a low creep regime, hand-operated tribometer. Wear; 265:1526–31, 2008. E. Magel, Y. Liu. Study of friction—measurement, analysis and practical implications for the wheel/rail contact. In: Proceedings of the eighth international conference on contact mechanics and wear of rail/wheel systems (CM2009), Firenze, Italy; September 15–18, 2009. S.R. Lewis, R. Lewis, G. Evans, Buckley-Johnstone LE. Assessment of railway grease performance using a twin-disc tester. Wear;314:205–12, 2014. D. Zapata, J. Jaramillo, H. Sierra, A. Toro. Desgaste de aceros bainíticos y perlíticos en el sistema rueda-riel. Memorias Tercer Congreso Internacional de Ingeniería Mecánica y Primero de Ingeniería Mecatrónica. Bogotá, Colombia, 2006. A. Kapoor, F.J. Franklin a, S.K. Wong a, M. Ishida. Surface roughness and plastic flow in rail wheel contact. Wear.Ed.253. p. 257-264, 2002. The U.K.’s Rail Safety & Standards Board, http://www.rssb.co.uk/, Project T355: Management and understanding of Rolling Contact Fatigue B. Bushan, Modern Tribology Handbook, V1, ISBN 0-8403-6, P 274-275,2001 F.A. Suárez. Análisis del Modelo de Archard para Desgaste por Deslizamiento en Seco. Trabajo de Grado. Universidad Nacional de Colombia, Medellín. p. 64. 2002. J.A.Williams. Engineering Tribology, Oxford University Press, Capitulo 11, 1994. R. Rabinowicz. Friction & Wear of Materials. John Wiley & Sons.Ed.1.p. 125- 233,1965. K.H. Zum Gahr.Microstructure and Wear of Materials. Elsevier. p. 351-524. 1987. M. Soler, M. Gentile. Tecnicatura superior en material rodante ferroviario, Universidad tecnológica nacional, 2005. G. Girsch, N. Frank, P. Pointner, New Rail Grades – a Technical Performance Overview, 8th IHHA Conference, Rio de Janeiro, Brazil, 2005. Y. Wang, T. Lei. Wear behavior of steel 1080 with different microstructures during dry sliding. Wear, 194, 44-53, 1996. D. Zapata. Efecto de la microestructura sobre la resistencia al desgaste por rodadura - deslizamiento de aceros ferroviarios. Trabajo de Grado. Universidad Nacional de Colombia, Medellín, 2011. M. Hillert. The Formation Of Pearlite, Descomposition Of Austenite by Diffusional Process eds. H.I. Aaronson & V.F. Zackay, interscience, pp. 197-247, 1962. F. P. García, R. W. Lewis, A. M. Tobias, and C. Roberts. Life cycle costs for railway condition monitoring. Transportation Research Part E: Logistics and Transportation Review, vol. 44, no. 6, pp. 1175–1187, Nov. 2008. Metro de Medellín, Reporte interno: Actividades de mantenimiento de vía permanente y vehículos de pasajeros relevantes para implementar la norma uic-518 en el metro de Medellín ltda, 2005 A. Toro, J.F. Santa, G. Idárraga y J. Sánchez. Identificación de mecanismos de desgaste en rieles de vía comercial del Metro de Medellín, Revista Colombiana de Materiales N. 5 pp. 72-77, 2013. U. Olofsson and R. Lewis. Basic tribology of the wheel-rail contact. Wheel-rail interface handbook, First Edition. ISBN 978-1-84569-412-8, Cap 2, 2006. D.I. Fletcher, F.J. Franklin, A. Kapoor. Rail surface fatigue and wear. Wheel-rail interface handbook, First Edition. ISBN 978-1-84569-412-8, Cap 9, 2006. Z.Y. Zhang, W. Shang, H.H. Ding, J. Guo, H.Y. Wang, Q.Y. Liu, W.J. Wang, Thermal model and temperature field in rail grinding process based on a moving heat source, Appl. Therm. Eng. 106 (2016) 855–864, http://dx.doi.org/10.1016/j. applthermaleng.2016.06.071. J. Ahlström, B. Karlsson. Analytical 1D model for analysis of the thermally affected zone formed during railway wheel skid, Wear 232 (1999) 15–24, http://dx.doi.org/ 10.1016/S0043-1648(99)00167-2. J. Kalousek, E. Magel, The “magic” wear rate, Railw. Track Struct. 50–52,1997. R.I. Carroll, J.H. Beynon. Rolling contact fatigue of white etching layer Part 1 Crack morphology, Wear 262 (2007) 1253–1266, http://dx.doi.org/10.1016/j.wear. 2007.01.002. G. Baumann, H.J. Fecht, S. Liebelt. Formation of white-etching layers on rail treads, Wear 191 (1996) 133–140, http://dx.doi.org/10.1016/0043-1648(95)06733-7. C.J. Rasmussen, X. Zhang, H.K. Danielsen, S. Fæster. Grinding induced martensite on the surface of rails, Risoe International Symposium on Materials Science. Proceedings 35439-446, 2014. C. J. Rasmussen, S. Fæsterb, S. Dharb, J. V. Quaadeb, M. Binib, H. K. Danielsenb. Surface crack formation on rails at grinding induced martensite white etching layers, Wear 384–385 8-14, 2017. R. Stock, W. Kubin, W. Daves, K. Six. Advanced maintenance strategies for improved squat mitigation. Wear 436-437, 2019. A. Al-Juboori, D. Wexler, H. Li, H. Zhu, C. Lu, A. McCusker, J. McLeod, S. Pannil, Z. Wang. Squat formation and the occurrence of two distinct classes of white etching layer on the surface of rail steel. International Journal of Fatigue 104, pp. 52-60, 2017. S. L. Grassie, D. I. Fletcher, E. A. Gallardo, P. Summers. Studs: a squat type defect in rails. Journal of Rail and Rapid Transit, pp. 243-256, 2012. S. L. Grassie. Studs and squats; The evolving story. Wear 366-367, pp. 194-199, 2016. Robel (2019). Maquinas Herramientas. https://www.robel.com/es/maquinas-herramientas/esmerilar/ (Revisado Diciembre 8, 2023) Klipartz (2019). Rieles ferroviarios. https://www.klipartz.com/es/search?q=riel (Revisado noviembre 18, 2023) Ghh-bonatrans (2019). Ejes montados. https://www.ghh-bonatrans.com/es/productos/ejes-montados/ (Revisado noviembre 18, 2023) K. Hono, M. Ohnuma, M. Murayama, S. Nishida, A. Yoshie, and T. Takahashi. Cementite decomposition in heavily drawn pearlite steel wire. Scr. Mater., vol. 44, pp. 977–983, 2001. M. Masoumi, N. B. De Lima, G. Tressia, A. Sinatora, and H. Goldenstein. Microstructure and crystallographic orientation evolutions below the superficial white layer of a used pearlitic rail. J. Mater. Res. Technol., vol. 8, no. 6, pp. 6275–6288, 2019, doi: 10.1016/j.jmrt.2019.10.021. J. Seo, S. Kwon, H. Jun, and D. Lee. Numerical stress analysis and rolling contact fatigue of White Etching Layer on rail steel. Int. J. Fatigue, vol. 33, no. 2, pp. 203–211, 2011, doi: 10.1016/j.ijfatigue.2010.08.007. D. T. Eadie et al. The effects of top of rail friction modifier on wear and rolling contact fatigue: Full-scale rail-wheel test rig evaluation, analysis and modelling. Wear, vol. 265, no. 9–10, pp. 1222–1230, 2008, doi: 10.1016/j.wear.2008.02.029. S. Li, J. Wu, R. H. Petrov, Z. Li, R. Dollevoet, and J. Sietsma. Brown etching layer: A possible ne insight into the crack initiation of rolling contact fatigue in rail steels. Eng. Fail. Anal., vol. 66, pp. 8–18, 2016, doi: 10.1016/j.engfailanal.2016.03.019. A. K. Saxena, A. Kumar, M. Herbig, S. Brinckmann, G. Dehm, and C. Kirchlechner. Micro fracture investigations of white etching layers. Mater. Des., vol. 180, p. 107892, 2019, doi: 10.1016/j.matdes.2019.107892. I. Marinescu, M. Hitchiner, E. Uhlmann, W. Brian, R. Ichiro. Handbook of Machining with Grinding Wheels. Taylor & Francis Group, 2007. W. Koenig, and F. Klocke. Fertigungsverfahren Band 2. Schleifen, Honen, Läppen. 3. Auflage, VDI Verlag GmbH, Düsseldorf, 1996.j J. Jaramillo. Efecto del acabado superficial inicial y la lubricación en el desgaste aceros de perlíticos bajo condiciones rodante deslizantes. Tesis de Maestría en ingeniería – materiales y procesos, Facultad de Minas, Universidad Nacional de Colombia, 2014. AENOR, Norma UNE – EN 13674. Aplicaciones ferroviarias. Vías y carriles. AENOR, Norma UNE – EN 13362. Aplicaciones ferroviarias. Ejes montados y Bogies. Ruedas. Requisitos de producto W.J. Wang, K. Zhou, Q.Y. Liu et al. Influence of granularity of grinding Stone on grinding force and material removal in the rail grinding process. Journal of Engineering Tribology 1994-1996 (vols 208-210) · June 2018 K. Zhou, H. Ding, R. Wang, J. Yang, J. Guo, Q. Liu, W. Wang W. Experimental investigation on material removal mechanism during rail grinding at different forward speeds. Tribology International (2019), doi: https://doi.org/10.1016/j.triboint.2019.106040. J.F. Santa, P. Cuervo, P. Christoforou, M. Harmon, A. Beagles, A. Toro, R. Twin disc assessment of wear regime transitions and rolling contact fatigue in R400HT – E8 pairs. Wear 432–433,102916, 2019. R. Stock, R. Pippan. Rail grade dependent damage behaviour–Characteristics and damage formation hypothesis, Wear 314 (1–2), 44–50, 2014. A. Kumar, G. Agarwal, R. Petrov, S.Goto, J. Sietsma, M. Herbig. Microstructural evolution of white and brown etching layers in pearlitic rail steels, Acta Materialia 171 (2019) 48 – 64, 2019. H. Ding, J. Yang, W. Wang, Q. Liu, J. Guo, Z. Zhou. Wear mechanisms of abrasive wheel for rail facing grinding, Wear 504-505, 204421, 2022. K. Zhou, H Ding, M, Steenbergen, W. Wang, J Guo, Q. Liu.Temperature field and material response as a function of rail grinding parameters, International Journal of Heat and Mass Transfer 175, 121366, 2021. P. Merino, S. Bouvier, S. Cazottes, J. Marteau, V. Lafil´, Y. Berthier. How to reproduce a mechanical white etching layer (WEL) on rail surface thanks to a new experimental wheel-rail contact test bench, Wear 482–483, 203945, 2021. B. Hieu, A. Al-Juboori, H. Zhu, Q. Zhu, H. Li, K. Tieu. Formation mechanism and evolution of white etching layers on different rail grades, International Journal of Fatigue 163, 107100, 2022. L. Wilches, L. Wang, B. Mellor, A. Schwedt, J. Mayer, W. Holweger. Characterisation of white etching structures formed in annealed AISI 52100 through High Pressure Torsion (HPT), Tribology International 184, 108432, 2023. L. Wilches, L Wang, B. Mellor, Y Huang. White etching structures in annealed 52100 bearing steel arising from high-pressure torsion tests, Tribology International 164, 10718 , 2022. |
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Universidad Nacional de Colombia - Nivel Nacional |
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Atribución-NoComercial-SinDerivadas 4.0 Internacionalhttp://creativecommons.org/licenses/by-nc-nd/4.0/info:eu-repo/semantics/openAccesshttp://purl.org/coar/access_right/c_abf2Toro, Alejandrocaada36313e95f5bd4f0bac9cc17128aSanta Marín, Juan Felipe30f321423032a600a1187f1d8ce07534Hernández Álvarez, Luis Guillermo4262b724f1a63a7ac035d1a5894aa7f3Grupo de Tribología y Superficies2024-05-02T19:07:32Z2024-05-02T19:07:32Z2023-12-08https://repositorio.unal.edu.co/handle/unal/86016Universidad Nacional de ColombiaRepositorio Institucional Universidad Nacional de Colombiahttps://repositorio.unal.edu.co/ilustraciones, fotografíasRail grinding is a maintenance operation carried out to remove surface and subsurface defects in rails, mainly those associated with rolling contact fatigue (RCF) and corrugation. However, rail grinding could promote the formation of a hard and fragile layer at the surface known as White Etching Layer (WEL). The presence of this layer has been associated with the early onset of RCF cracks. In this study, R400HT rail samples were ground in laboratory under controlled conditions that promote the formation of the WEL. The samples were submitted to accelerated contact fatigue tests at 20,000 cycles (8,000 cycles dry + 12,000 cycles with water) in a twin-disc tribometer, in which the wear rate and the coefficient of friction were determined. The results showed that under different grinding conditions, all tested samples developed the WEL at the surface. The samples with WEL presented higher wear and density of cracks compared to WEL-free samples for the same number of cycles. The onset of cracking was influenced by the presence of the WEL since as the WEL-perlite interface was a preferential site for crack initiation.Rail grinding is a maintenance operation carried out to remove surface and subsurface defects in rails, mainly those associated with rolling contact fatigue (RCF) and corrugation. However, rail grinding could promote the formation of a hard and fragile layer at the surface known as White Etching Layer (WEL). The presence of this layer has been associated with the early onset of RCF cracks. In this study, R400HT rail samples were ground in laboratory under controlled conditions that promote the formation of the WEL. The samples were submitted to accelerated contact fatigue tests at 20,000 cycles (8,000 cycles dry + 12,000 cycles with water) in a twin-disc tribometer, in which the wear rate and the coefficient of friction were determined. The results showed that under different grinding conditions, all tested samples developed the WEL at the surface. The samples with WEL presented higher wear and density of cracks compared to WEL-free samples for the same number of cycles. The onset of cracking was influenced by the presence of the WEL since as the WEL-perlite interface was a preferential site for crack initiation.El esmerilado de rieles constituye una operación de mantenimiento destinada a corregir defectos superficiales y subsuperficiales presentes en los mismos, especialmente aquellos derivados de la fatiga por contacto con rodadura (RCF) y a la formación de corrugaciones. Sin embargo, el esmerilado de rieles puede inducir la formación de una capa dura y frágil en la superficie conocida como capa blanca. La presencia de esa capa se ha asociado con una aparición temprana de grietas por RCF. En este trabajo, se esmerilaron muestras de rieles R400HT en laboratorio bajo condiciones controladas que promueven la formación de capa blanca. Se sometieron tanto muestras esmeriladas como no esmeriladas a pruebas de fatiga de contacto aceleradas a 20K ciclos (8K ciclos en seco + 12K ciclos con agua) en un tribómetro tipo disco-disco, con el objetivo de determinar la tasa de desgaste y el coeficiente de fricción. Los resultados revelaron que todas las muestras probadas, bajo diferentes condiciones de esmerilado, desarrollaron una capa blanca en sus superficies. Aquellas muestras con esta capa blanca exhibieron un mayor desgaste y una mayor densidad de grietas en comparación con las muestras sin esmerilar, para el mismo número de ciclos de fatiga. Además, se observó que el inicio del agrietamiento fue influenciado por la presencia de la capa blanca, dado que la interfaz entre la capa blanca y la perlita se convirtió en un sitio preferencial para el inicio de las grietas. (Tomado de la fuente)MaestríaMagíster en Ingeniería - Materiales y ProcesosTribología y superficiesMateriales Y Nanotecnología.Sede Medellín134 páginasapplication/pdfspaUniversidad Nacional de ColombiaMedellín - Minas - Maestría en Ingeniería - Materiales y ProcesosFacultad de MinasMedellín, ColombiaUniversidad Nacional de Colombia - Nivel Nacional380 - Comercio , comunicaciones, transporte::385 - Transporte ferroviario620 - Ingeniería y operaciones afines::625 - Ingeniería de ferrocarriles y de carreteraMetro (Sistema de transporte) - Medellín (Colombia)Transporte ferroviario - Medellín (Colombia)Rieles - EsmeriladoMetro (Sistema de transporte) - Mantenimiento y reparaciónFatiga de materialesResistencia de materialesEsmerilado de rielesCapa blancaFatiga por contacto de rodaduraEnsayos disco-discoAgrietamientoRail grindingTwin-disc testsWhite Etching Layer (WEL)Rolling contact fatiguecrackingInfluencia de las condiciones de esmerilado sobre la aparición de capa blanca en rieles tipo R400HT para uso en el Metro de MedellínInfluence of grinding conditions on the formation of the white layer in R400HT rails for use in the Metro de MedellínTrabajo de grado - Maestríainfo:eu-repo/semantics/masterThesisinfo:eu-repo/semantics/acceptedVersionTexthttp://purl.org/redcol/resource_type/TMMedellín (Antioquia, Colombia)LaReferenciaC.R Ferguson, A.T Kirkpatrick, Motores de combustión interna (2 ª ed.) 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White etching structures in annealed 52100 bearing steel arising from high-pressure torsion tests, Tribology International 164, 10718 , 2022.EstudiantesInvestigadoresMaestrosPúblico generalLICENSElicense.txtlicense.txttext/plain; charset=utf-85879https://repositorio.unal.edu.co/bitstream/unal/86016/1/license.txteb34b1cf90b7e1103fc9dfd26be24b4aMD51ORIGINAL71316155.2023.pdf71316155.2023.pdfTesis de Maestría en Ingeniería - Materiales y Procesosapplication/pdf5515882https://repositorio.unal.edu.co/bitstream/unal/86016/2/71316155.2023.pdfb7c978fa9c9af99891356576a0e5218cMD52unal/86016oai:repositorio.unal.edu.co:unal/860162024-05-02 14:10:04.663Repositorio Institucional Universidad Nacional de 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