Download or read book Development of a Multiple Specimen Test Methodology for Fatigue Crack Growth Rate Determination written by Frederic R. Deshayes and published by . This book was released on 1991 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Development of a Fatigue Crack Growth Rate Specimen Suitable for a Multiple Specimen Test Configeration written by FR. Deshayes and published by . This book was released on 1993 with total page 21 pages. Available in PDF, EPUB and Kindle. Book excerpt: A new experimental approach developed by fatigue crack growth rates can be determined for multiple specimens tested in series. This involves a geometry such that the response to cyclic loading in each specimen is mutually independent. Relationships between the stress intensity factor, compliance, and crack length and between direct-current potential drop and crack length have been analytically evaluated for the proposed specimen geometry. An appropriate side-groove depth that avoided crack deviation from the intended plane of extension was determined experimentally, and an analytical expression that accounted for reduced thickness in the crack plane was verified. Calibration curves between crack length and compliance and between crack length and potential drop were experimentally verified as well, and the stress intensity-crack length characteristics for the specimen were confirmed by comparing da/dN-?KI curves with those for conventional C(T) specimens. A customized, five specimen frame was designed and fabricated in conjunction with a 98-kN MTS actuator and interfaced with a commercially available control system, the hardware and software of which were modified to accommodate multiple-specimen control and data acquisition. The utility of the proposed specimen and test procedure is discussed within the context of threshold and near-threshold crack growth rate determinations where long test times are normally required for data development, particularly for low cyclic frequency applications such as nuclear and offshore.

Download or read book Fracture Mechanics written by Ravinder Chona and published by ASTM International. This book was released on 1993 with total page 864 pages. Available in PDF, EPUB and Kindle. Book excerpt: The proceedings of the 23rd National Symposium on Fracture Mechanics, held in College Station, Texas, June 1991, present a broad overview of the current state of the art in fracture mechanics research. Following the Swerdlow Lecture (Structural Problems in Search of Fracture Mechanics Solutions by

Download or read book Fatigue Crack Growth Measurement and Data Analysis written by S. J Hudak and published by ASTM International. This book was released on 1981 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Practical Engineering Approach to Predicting Fatigue Crack Growth in Riveted Lap Joints written by C. E. Harris and published by . This book was released on 2000 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: An extensive experimental database has been assembled from very detailed teardown examinations of fatigue cracks found in rivet holes of fuselage structural components. Based on this experimental database, a comprehensive analysis methodology was developed to predict the onset of widespread fatigue damage in lap joints of fuselage structure. Several computer codes were developed with specialized capabilities to conduct the various analyses that make up the comprehensive methodology. Over the past several years, the authors have interrogated various aspects of the analysis methods to determine the degree of computational rigor required to produce numerical predictions with acceptable engineering accuracy. This study led to the formulation of a practical engineering approach to predicting fatigue crack growth in riveted lap joints. This paper describes the practical engineering approach and compares predictions with the results from several experimental studies.

Download or read book The Measurement of Crack Length and Shape During Fracture and Fatigue written by C. J. Beevers and published by . This book was released on 1980 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Methods and Models for Predicting Fatigue Crack Growth Under Random Loading written by and published by ASTM International. This book was released on with total page 147 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fatigue Damage Crack Growth and Life Prediction written by F. Ellyin and published by Springer Science & Business Media. This book was released on 1996-11-30 with total page 490 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fatigue failure is a multi-stage process. It begins with the initiation of cracks, and with continued cyclic loading the cracks propagate, finally leading to the rupture of a component or specimen. The demarcation between the above stages is not well-defined. Depending upon the scale of interest, the variation may span three orders of magnitude. For example, to a material scientist an initiated crack may be of the order of a micron, whereas for an engineer it can be of the order of a millimetre. It is not surprising therefore to see that investigation of the fatigue process has followed different paths depending upon the scale of phenomenon under investigation. Interest in the study of fatigue failure increased with the advent of industrial ization. Because of the urgent need to design against fatigue failure, early investiga tors focused on prototype testing and proposed failure criteria similar to design formulae. Thus, a methodology developed whereby the fatigue theories were proposed based on experimental observations, albeit at times with limited scope. This type of phenomenological approach progressed rapidly during the past four decades as closed-loop testing machines became available.

Download or read book Variability in Fatigue Crack Growth Rate Testing written by S. J. Hudak and published by . This book was released on 1974 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nano and Microstructural Design of Advanced Materials written by M. A. Meyers and published by Elsevier. This book was released on 2003-12-05 with total page 317 pages. Available in PDF, EPUB and Kindle. Book excerpt: The importance of the nanoscale effects has been recognized in materials research for over fifty years, but it is only recently that advanced characterization and fabrication methods are enabling scientists to build structures atom-by-atom or molecule-by molecule. The understanding and control of the nanostructure has been, to a large extent, made possible by new atomistic analysis and characterization methods pioneered by transmission electron microscopy. Nano and Microstructural Design of Advanced Materials focuses on the effective use of such advanced analysis and characterization techniques in the design of materials. - Teaches effective use of advanced analysis and characterization methods at an atomistic level - Contains many supporting examples of materials in which such design concepts have been successfully applied

Download or read book A Test Procedure for Determining the Influence of Stress Ratio on Fatigue Crack Growth written by JH. FitzGerald and published by . This book was released on 1974 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: A test procedure is outlined by which the rate of fatigue crack growth over a range of stress ratios and stress intensities can be determined expeditiously using a small number of specimens. This procedure was developed to avoid or circumvent the effects of load interactions on fatigue crack growth, and was used to develop data on a mill annealed Ti-6Al-4V alloy plate. Experimental data suggest that the rates of fatigue crack growth among the various stress ratios may be correlated in terms of an effective stress intensity range, ? Keff, at given values of Kmax.

Download or read book Automated Test Methods for Fracture and Fatigue Crack Growth written by W. H. Cullen and published by ASTM International. This book was released on 1985 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fatigue Crack Growth in Rubber Materials written by Gert Heinrich and published by Springer Nature. This book was released on 2021-03-23 with total page 491 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book summarizes recent international research and experimental developments regarding fatigue crack growth investigations of rubber materials. It shows the progress in fundamental as well as advanced research of fracture investigation of rubber material under fatigue loading conditions, especially from the experimental point of view. However, some chapters will describe the progress in numerical modeling and physical description of fracture mechanics and cavitation phenomena in rubbers. Initiation and propagation of cracks in rubber materials are dominant phenomena which determine the lifetime of these soft rubber materials and, as a consequence, the lifetime of the corresponding final rubber parts in various fields of application. Recently, these phenomena became of great scientific interest due to the development of new experimental methods, concepts and models. Furthermore, crack phenomena have an extraordinary impact on rubber wear and abrasion of automotive tires; and understanding of crack initiation and growth in rubbers will help to support the growthing number of activities and worldwide efforts of reduction of tire wear losses and abrasion based emissions.

Download or read book Development of Basic Material s Data for Evaluating Crack Growth Life written by RJ. Bucci and published by . This book was released on 1979 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fracture toughness, fatigue crack growth rate, and sustained load crack growth data comprise a basic package of materials property information used in predicting growth of cracks by fracture mechanics methods. Accurate analysis requires carefully developed laboratory results using various simple specimen configurations to describe these properties. A contributing factor to variability in life prediction is the lack of consistent procedures for obtaining and reporting this information for use in design. Though a standard does exist for direct fracture toughness determinations (ASTM Method E 399), standards for subcritical crack growth measurement are in various stages of development. Accuracy of life prediction is further confounded by judgment required of the analyst in selecting the most appropriate test and interpreting material property data for use in the computational methodology.

Download or read book Advances in Fatigue Crack Closure Measurement and Analysis written by R. Craig McClung and published by ASTM International. This book was released on 1999 with total page 487 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Investigation of Constraint Effect on Fatigue Crack Growth Rate Measurements written by Veronika Hochfellner and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: For the purpose of reliable life prediction the fatigue crack growth behaviour of a material has to be well-known. Therefore standardized fatigue crack growth tests are made with test specimens of the material. The obtained fatigue crack growth data is taken as material specific data and is given without any information of the test conditions and used specimen geometry. However, in several studies a geometry dependency of the test specimen on the fatigue crack growth data is found. Hence in this investigation experiments on fatigue crack growth behaviour are made with two different specimen geometries, the middle tension specimen M(T) and the compact (tension) specimen C(T). The direct current potential drop (DCPD) method is used to determine the crack lengths which is calibrated with the aid of beach marks and crack detection gauges. Two different configurations of the DCPD method are implemented to gain acceptable results. With the obtained data fatigue crack growth curves are established which are analysed regarding the geometry influence of the used test specimens. Discrepancies in the fatigue crack growth curves between the tested specimens are found. With these findings an approach is tested to create a material curve which is independent of the specimen geometry. However, this approach is not leading to satisfactory results. The implementation of the DCPD method in its main configuration on the used experimental setup proves to be applicable for fatigue crack growth tests on different geometries and will be used in further studies at low temperatures.

Download or read book Prediction of Fatigue Crack Growth Under Constant Amplitude and Random Loading Using Specimens with Multiple Cracks written by and published by . This book was released on 1994 with total page 78 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fatigue crack growth under stationary Gaussian random loading is considered. A specially developed computerized testing system and software are used for generation of the random loading and investigation of crack growth. The sliding summation numerical method was used for generation of a random loading history characterized by a given autocorrelation function. As far as the loading history of a sufficient length is generated a sequence of maxima and minima is extracted and arranged with the predetermined frequency. The next Operation is elimination of the small amplitude cycles in accordance with the predetermined threshold value and. determination of the minima and maxima two-dimensional distribution of the edited process. A specially built transition matrix derived from this distribution was used for the real-time generation of the random loading during the test. Experimental investigation of the developed random loading generation procedure and crack growth process was performed using aluminium alloy multicrack panel type specimens providing possibility of observation of an array of simultaneously growing cracks. Dependence of fatigue crack life time on random loading parameters as well as stochastic characteristics of crack growth were studied. (MM).