Download or read book Fatigue Life of a SG Cast Iron Under Real Loading Spectra written by J-F Vittori and published by . This book was released on 2004 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper deals with the effect on life of the desynchronism between two variable amplitude load sequences in combined bending and torsion. Experiments were carried out on smooth specimens made of the EN-GJS800-2 cast iron. The comparison between experimental lives and predicted ones with the following fatigue life calculation methods is presented: Smith-Watson-Topper, Fatemi and Socie (method proposed by Bannantine), Wang and Brown, Socie's proposal for high cycle fatigue, and Morel. If the scatter of experiments is considered, these experiments show a low effect of the correlation factor on life. All the simulated fatigue life calculation methods give good results for proportional loads, but their predictions are not good for non-proportional loads. Morel's proposal seems to be the best to predict life of the tested material with our non-proportional fatigue test conditions.
Download or read book Fatigue Testing and Analysis Under Variable Amplitude Loading Conditions written by Peter C. McKeighan and published by ASTM International. This book was released on 2005 with total page 588 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Particle and Continuum Aspects of Mesomechanics written by George C. Sih and published by John Wiley & Sons. This book was released on 2010-01-05 with total page 837 pages. Available in PDF, EPUB and Kindle. Book excerpt: This title brings together a variety of papers presented at the 9th annual Meso meeting in 2007. The topics selected for Meso 2007 are designed to illustrate the relation of thresholds to multiscaling: Flow through capillary tubes in contrast to pipes Laminar and turbulent flow transition Heat convection of thin wires in contrast to cylinders Electrical conductance of macro- and nano-circuits Rubbery and glassy polymers Single- and poly-crystal behavior Strength of wires and round cylindrical bars Uni-axial and multi-axial material: linear and non-linear response Thin and thick plate behavior Brittle and ductile fracture Small and large crack growth behavior Low and high temperature effects Local and global material property characteristics Small and large bodies: size and time effects Specimen and structure
Download or read book Residual stresses fatigue and deformation in cast iron written by Mattias Lundberg and published by Linköping University Electronic Press. This book was released on 2018-09-03 with total page 59 pages. Available in PDF, EPUB and Kindle. Book excerpt: The complex geometry of cylinder heads in heavy-duty diesel engines makes grey iron or compact graphite iron a preferred material choice due to its price, castability, thermal conductivity and damping capacity. Today’s strict emission laws have increased the demands on engine performance and engine efficiency. This means that material properties such as fatigue resistance need to be improved. Shot peening is often used to improve the fatigue resistance of components and the benefits of shot peening are associated with the induced compressive surface stresses and surface hardening. How different shot peening parameters can affect fatigue strength of grey and compact graphite iron has been investigated within the project underlying this thesis. To do this, X-ray diffraction (XRD) was utilized for residual stress measurements, scanning electron microscopy (SEM) for microstructural characterizations and mechanical fatigue testing for mechanical quantifications. The ultimate aim of this work has been to increase the fatigue resistance of cast iron by residual stress optimization. XRD measurements and SEM examinations revealed that the shot peening parameters shot size and peening intensity significantly influence residual stresses and surface deformation. Residual stress profiles, similar to the one general considered to improve the fatigue strength in steels, were obtained for both grey and compact graphite iron. Uniaxial push-pull fatigue testing on grey iron with these shot peening parameters reduced the fatigue strength with 15–20 %. The negative effect is likely related to surface damage associated with over peening and relatively high subsurface tensile residual stresses. With very gentle shot peening parameters, the uniaxial fatigue strength were unaltered from the base material but when subjected to bending fatigue an increase in fatigue strength were observed. An alternative way to increase the fatigue strength was to conduct a 30 min annealing heat treatment at 285 XC which increased the fatigue strength by almost 10 % in uniaxial loading. The improvement could be an effect of favourable precipitates forming during the annealing, which could hinder dislocation movement during fatigue. Measuring residual stresses using XRD and the sin2 -method demands accurate X-ray elastic constants (XEC) for meticulous stress analysis. The XEC referred to as 1~2s2 should therefore always be calibrated for the specific material used. The experiments conducted revealed that the XEC value is independent of the testing method used in this work. A small correction from the theoretical value should be applied when the material contains small amounts of residual stresses. The amount of residual stresses has a great impact on the XEC and thus on the stress analysis. Concluding that proper analysis of residual stresses in cast iron is not straight forward.
Download or read book The Influence of Fretting Corrosion on Fatigue Strength of Nodular Cast Iron and Steel Under Constant Amplitude and Load Spectrum Tests written by O. Buxbaum and published by . This book was released on 1992 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: The fatigue life reduction caused by fretting corrosion was determined in comparative fatigue life tests for axially loaded flat specimens made of GGG 40 (cast nodular iron, ASTM A 536-80: 60-40-12) and of St 34-2 (hot rolled structural steel, ASTM A 283-78: Grade C). A special test rig was constructed for superimposing fretting corrosion onto constant amplitude and spectrum loading of the specimen. Various surface conditions and two levels of surface pressure were investigated. Using the results of these tests and the parameters derived, comparative damage calculations were performed aiming at predicting fatigue life in the presence of fretting corrosion. Means to avoid fretting corrosion were also explained.
Download or read book Tests of the Fatigue Strength of Cast Iron written by Edward Charles Schmidt and published by . This book was released on 1927 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Modeling Cyclic Deformation and Fatigue Behavior of Cast Iron Under Uniaxial Loading written by Stephen Douglas Downing and published by . This book was released on 1983 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Mean Stress and Stress Concentration on Fatigue Behavior of Ductile Iron written by Nicholas Meyer and published by . This book was released on 2014 with total page 207 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cast iron tends to be more economical to manufacture than steel, but its microstructure is riddled with internal defects. With improvements in casting technology, cast iron can compete with steel in some applications due to the ability to maintain similar strength. One objective of this study was to analyze data obtained from literature and make predictive correlations between tensile, microstructural, and fatigue properties. Another objective of this study was to evaluate tensile and compressive mean stress effects on smooth and notched fatigue behavior of 120-90-02 ductile cast iron experimentally, as well as analytically by using predictive models. The relationship between these two objectives is such that with successful correlations of fatigue limit with mechanical properties, fewer experiments could be performed to verify analytical results. This grade of cast iron was selected by Eaton Corporation, who helped fund this study. The material, 120-90-02 ductile cast iron, was machined and heat-treated as provided by Eaton Corporation. Neuber's rule, strain energy density, and finite element methods were used to obtain stresses and strains at the notch. Modified Goodman, Smith- iv Watson-Topper, FKM and the Fatemi-Socie mean stress parameters were used to account for mean stress effect on fatigue life of both smooth and notched specimens. Mean stress levels were chosen such that the R-ratios in load-controlled tests were -8, -7, -3, -1, 0, 1/3, 0.5, and 0.75. By understanding the fatigue behavior of material under varying degrees of mean stress, design safety can be improved by properly accounting for the effect of mean stress that a component may be subjected to. The Smith-Watson-Topper mean stress parameter proved to be the best method for life prediction for both smooth and notched specimens, based on the nominal stress approach. Using the local approach, which considers notch root stresses and strains, the Fatemi-Socie fatigue parameter used with the strain energy density rule provided better results compared to the Smith-Watson-Topper mean stress parameter.
Download or read book Fatigue Crack Growth in Gray Cast Iron Under Block Loading Histories written by Gary Burton Marquis and published by . This book was released on 1984 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Endurance Limit Design of Spheroidal Graphite Cast Iron Components Based on Natural Defects written by L. Siivonen and published by . This book was released on 2000 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cast irons are used extensively in the production of large diesel engines for power generation or oceangoing ships. One current trend is to replace grey iron with spheroidal graphite (SG) iron for fatigue critical components. In order to take advantage of the higher fatigue strength of SG iron and ensure the reliability of a design, better understanding of the typical defects for these large castings and the relationship between these defects and the endurance limit fatigue strength have been studied. Testing included uniaxial constant amplitude, constant amplitude torsion, and simple variable amplitude loading sequences in the long-life regime. Defects in several thick wall castings have been statistically evaluated. A fracture mechanics based model involving matrix hardness and ?area successfully related the defect size to the experimentally observed fatigue limit. For ferritic-pearlitic SG iron, the hardness of the tougher pearlite phase was used in the model. The model also correlated the torsion and tension endurance limits. Endurance limit as a function of mean stress is presented in the form of Haigh diagrams.
Download or read book Fatigue Behavior of Gray Cast Iron Under Torsional Loads written by Daniel Joseph Weinacht and published by . This book was released on 1986 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fatigue Crack Growth in Gray Cast Iron Under Step Loading Histories written by Gary B. Marquis and published by . This book was released on 1984 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Strain life Fatigue Properties Database for Cast Iron written by James D. DeLa'O and published by . This book was released on 2003 with total page 39 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fatigue Behavior of Gray Cast Iron Under Axial and Bending Loads written by Peter J. Furman and published by . This book was released on 1985 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book High Cycle Variable Amplitude Fatigue of a Nodular Cast Iron written by GB. Marquis and published by . This book was released on 2004 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper provides a brief summary of life prediction methods for variable amplitude fatigue. Special attention is given to cracks propagating from nominally defect free components in the high cycle regime where a significant portion of the fatigue damage can be attributed to cycles with amplitude less than the fatigue limit observed under constant amplitude loading. Constant and variable amplitude fatigue data for a nodular cast iron are presented. An effective stress method for variable amplitude loaded similar to the Topper model is developed. Most model parameters are derived from constant amplitude S-N curves and the Haigh diagram, but two sets of long life variable amplitude tests are needed to derive the variable amplitude interaction parameters.
Download or read book The Relation Between Load Spectra and Fatigue Life written by Bo K. O. Lundberg and published by . This book was released on 1956 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Modeling of Cyclic Deformation and Fatigue Behavior of Cast Iron Unaxial Loading written by Stephen Douglas Downing and published by . This book was released on 1983 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
