The Experts below are selected from a list of 291 Experts worldwide ranked by ideXlab platform
Jonas W. Ringsberg - One of the best experts on this subject based on the ideXlab platform.
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Modelling of Rolling Contact fatigue of rails
2002Co-Authors: Jonas W. Ringsberg, Lennart JosefsonAbstract:Railway rails of today are subjected to higher train traffic density, higher train speeds, and heavier axle loads, than some 10 years ago. As a result, Rolling Contact fatigue (RCF) damage (cracking, wear) has accelerated. It has now become a major concern for the community, both with respect to train traffic safety and maintenance costs. The present paper is a summary of work done on the numerical modelling, simulation, and analysis of RCF of railway rails. Fatigue life prediction of surface crack initiation, influence of rail residual stresses on rail life, butt-welding of rails, laser cladding of rails, and short crack propagation are presented. The work has been performed in the EU project ICON (Integrated study of Rolling Contact fatigue), the Swedish National Centre of Excellence CHARMEC (CHAlmers Railway MECHanics), and the EU project INFRASTAR. For the covering abstract see ITRD E122683.
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life prediction of Rolling Contact fatigue crack initiation
International Journal of Fatigue, 2001Co-Authors: Jonas W. RingsbergAbstract:Abstract A strategy developed for fatigue life prediction of Rolling Contact fatigue (RCF) crack initiation is presented. It combines elastic–plastic finite element (FE) analyses, multiaxial fatigue crack initiation models used together with the critical plane concept, fatigue damage summation calculations, and comparison of results from numerical analyses and experiments. The strategy presented is utilised and evaluated for two RCF examples: (i) a twin disc test, and (ii) a railway wheel–rail Rolling Contact. The results from both of the examples verify that the strategy and evaluation methodology presented can be used for fatigue life predictions of RCF crack initiation caused by low-cycle fatigue and ratchetting failure.
A Kadiric - One of the best experts on this subject based on the ideXlab platform.
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propagation of surface initiated Rolling Contact fatigue cracks in bearing steel
International Journal of Fatigue, 2017Co-Authors: Pawel Rycerz, A V Olver, A KadiricAbstract:Abstract Surface initiated Rolling Contact fatigue, leading to a surface failure known as pitting, is a life limiting failure mode in many modern machine elements, particularly Rolling element bearings. Most research on Rolling Contact fatigue considers total life to pitting. Instead, this work studies the growth of Rolling Contact fatigue cracks before they develop into surface pits in an attempt to better understand crack propagation mechanisms. A triple-Contact disc machine was used to perform pitting experiments on bearing steel samples under closely controlled Contact conditions in mixed lubrication regime. Crack growth across the specimen surface was monitored and crack propagation rates extracted. The morphology of the generated cracks was observed by preparing sections of cracked specimens at the end of the test. It was found that crack initiation occurred very early in total life, which was attributed to high asperity stresses due to mixed lubrication regime. Total life to pitting was dominated by crack propagation. Results provide direct evidence of two distinct stages of crack growth in Rolling Contact fatigue: stage 1, within which cracks grow at a slow and relatively steady rate, consumed most of the total life; and stage 2, reached at a critical crack length, within which the propagation rate rapidly increases. Contact pressure and crack size were shown to be the main parameters contRolling the propagation rate. Results show that crack propagation under Rolling Contact fatigue follows similar trends to those known to occur in classical fatigue. A log-log plot of measured crack growth rates against the product of maximum Contact pressure and the square root of crack length, a parameter describing the applied stress intensity, produces a straight line for stage 2 propagation. This provides the first evidence that growth of hereby-identified stage 2 Rolling Contact fatigue cracks can be described by a Paris-type power law, where the rate of crack growth across the surface is proportional to the Contact pressure raised to a power of approximately 7.5.
Pawel Rycerz - One of the best experts on this subject based on the ideXlab platform.
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propagation of surface initiated Rolling Contact fatigue cracks in bearing steel
International Journal of Fatigue, 2017Co-Authors: Pawel Rycerz, A V Olver, A KadiricAbstract:Abstract Surface initiated Rolling Contact fatigue, leading to a surface failure known as pitting, is a life limiting failure mode in many modern machine elements, particularly Rolling element bearings. Most research on Rolling Contact fatigue considers total life to pitting. Instead, this work studies the growth of Rolling Contact fatigue cracks before they develop into surface pits in an attempt to better understand crack propagation mechanisms. A triple-Contact disc machine was used to perform pitting experiments on bearing steel samples under closely controlled Contact conditions in mixed lubrication regime. Crack growth across the specimen surface was monitored and crack propagation rates extracted. The morphology of the generated cracks was observed by preparing sections of cracked specimens at the end of the test. It was found that crack initiation occurred very early in total life, which was attributed to high asperity stresses due to mixed lubrication regime. Total life to pitting was dominated by crack propagation. Results provide direct evidence of two distinct stages of crack growth in Rolling Contact fatigue: stage 1, within which cracks grow at a slow and relatively steady rate, consumed most of the total life; and stage 2, reached at a critical crack length, within which the propagation rate rapidly increases. Contact pressure and crack size were shown to be the main parameters contRolling the propagation rate. Results show that crack propagation under Rolling Contact fatigue follows similar trends to those known to occur in classical fatigue. A log-log plot of measured crack growth rates against the product of maximum Contact pressure and the square root of crack length, a parameter describing the applied stress intensity, produces a straight line for stage 2 propagation. This provides the first evidence that growth of hereby-identified stage 2 Rolling Contact fatigue cracks can be described by a Paris-type power law, where the rate of crack growth across the surface is proportional to the Contact pressure raised to a power of approximately 7.5.
J. J. Kalker - One of the best experts on this subject based on the ideXlab platform.
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Rolling Contact Phenomena - Rolling Contact phenomena
Rolling Contact Phenomena, 2000Co-Authors: Bo O. Jacobson, J. J. KalkerAbstract:In this paper, we treat the Rolling Contact phenomena of linear elasticity, with special emphasis on the elastic half-space.
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Rolling Contact phenomena
2000Co-Authors: Bo O. Jacobson, J. J. KalkerAbstract:In this paper, we treat the Rolling Contact phenomena of linear elasticity, with special emphasis on the elastic half-space.
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Crack Behaviour under Rolling Contact Fatigue
Rail Quality and Maintenance for Modern Railway Operation, 1993Co-Authors: M. C. Dubourg, J. J. KalkerAbstract:A theoretical approach on surface crack influence on Rolling Contact stress field is presented. A steady Rolling Contact model and a fatigue crack model are combined. Connection between the two problems is introduced through surface geometry modification caused by displacements generated by cracks. Split up of Contact area, maximum pressure increases are highlighted. No significant stress intensity factor variations are obtained.
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Three-Dimensional Elastic Bodies in Rolling Contact
1990Co-Authors: J. J. Kalker, K. L. JohnsonAbstract:1 The Rolling Contact Problem.- 2 Review.- 3 The Simplified Theory of Contact.- 4 Variational and Numerical Theory of Contact.- 5 Results.- 6 Conclusion.- Appendix A The basic equations of the linear theory of elasticity.- Appendix B Some notions of mathematical programming.- Appendix C Numerical calculation of the elastic field in a half-space.- Appendix D Three-dimensional viscoelastic bodies in steady state frictional Rolling Contact with generalisation to Contact perturbations.- Appendix E Tables.
A V Olver - One of the best experts on this subject based on the ideXlab platform.
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propagation of surface initiated Rolling Contact fatigue cracks in bearing steel
International Journal of Fatigue, 2017Co-Authors: Pawel Rycerz, A V Olver, A KadiricAbstract:Abstract Surface initiated Rolling Contact fatigue, leading to a surface failure known as pitting, is a life limiting failure mode in many modern machine elements, particularly Rolling element bearings. Most research on Rolling Contact fatigue considers total life to pitting. Instead, this work studies the growth of Rolling Contact fatigue cracks before they develop into surface pits in an attempt to better understand crack propagation mechanisms. A triple-Contact disc machine was used to perform pitting experiments on bearing steel samples under closely controlled Contact conditions in mixed lubrication regime. Crack growth across the specimen surface was monitored and crack propagation rates extracted. The morphology of the generated cracks was observed by preparing sections of cracked specimens at the end of the test. It was found that crack initiation occurred very early in total life, which was attributed to high asperity stresses due to mixed lubrication regime. Total life to pitting was dominated by crack propagation. Results provide direct evidence of two distinct stages of crack growth in Rolling Contact fatigue: stage 1, within which cracks grow at a slow and relatively steady rate, consumed most of the total life; and stage 2, reached at a critical crack length, within which the propagation rate rapidly increases. Contact pressure and crack size were shown to be the main parameters contRolling the propagation rate. Results show that crack propagation under Rolling Contact fatigue follows similar trends to those known to occur in classical fatigue. A log-log plot of measured crack growth rates against the product of maximum Contact pressure and the square root of crack length, a parameter describing the applied stress intensity, produces a straight line for stage 2 propagation. This provides the first evidence that growth of hereby-identified stage 2 Rolling Contact fatigue cracks can be described by a Paris-type power law, where the rate of crack growth across the surface is proportional to the Contact pressure raised to a power of approximately 7.5.
