Download or read book Effect of Transient Loads on Fatigue Crack Growth in Mill Annealed Ti 62222 at 54 25 and 175 C written by RR. Stephens and published by . This book was released on 2003 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: Transient loads consisting of single tensile overloads and single tensile overloads followed by single compressive underloads were applied to Ti-62222 mill annealed titanium alloy at -54, 25, and 175°C. Tensile overload ratios were 2.0 and 2.5 and the compressive underload ratio was -0.5. Four reference steady-state ?KImp values, using constant ?K testing at R = 0.1, were investigated at each temperature. Cycles of delay, fatigue crack growth during delay, minimum fatigue crack growth rate, and crack extension during a transient load were obtained for all tests. Cycles of delay ranged from zero to crack arrest and mixed results often occurred making it difficult to draw many specific conclusions. Higher tensile overloads caused greater delay cycles and underloads were often detrimental compared to overloads only. Low temperature was mostly beneficial compared to room and high temperature that yielded similar delay. Crack growth delay distance was always greater than reversed plastic zone size. Macro- and microfractography revealed that surface crack closure, mode II displacements, crack tip blunting, branching, and tunneling, local state of stress, and residual compressive stresses contributed to the transient fatigue crack growth behavior.
Download or read book Effects of Transient Loads on Fatigue Crack Growth in Mill Annealed Ti 62222 at 540C 250C and 1750C written by Dwight Alan Schoenefeld and published by . This book was released on 1999 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of Transient Loads on Fatigue Crack Growth in Solution Treated and Aged Ti 62222 at 54 25 and 175 C written by RR. Stephens and published by . This book was released on 2004 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: Transient loads consisting of single tensile overloads and single tensile overloads followed by single compressive underloads were applied to Ti-62222 solution treated and aged titanium alloy at -54, 25, and 175°C. Tensile overload ratios were 2.0 and 2.5, and the compressive underload ratio was -0.5. Four reference steady state ?Kss values, using constant ?K testing at R = 0.1, were investigated at each temperature. Cycles of delay, fatigue crack growth during delay, and minimum fatigue crack growth rate during a transient load were obtained for all tests. Cycles of delay ranged from zero to crack arrest. Higher tensile overloads caused greater delay cycles, and underloads were often detrimental. Low and high temperatures were primarily beneficial to delay cycles relative to those at room temperature. Crack growth delay distance was always greater than the pertinent reversed plastic zone size. Fatigue crack growth life predictions were made using FASTRAN III and AFGROW computer programs and produced both conservative and non-conservative results with more than half the predictions being within ± 2 of the experimental results. Macro- and microfractography revealed surface crack closure, Mode II displacements, crack tip blunting, branching, and tunneling contributed to the transient fatigue crack growth behavior.
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 Fatigue and Fracture Mechanics written by Walter G. Reuter and published by ASTM International. This book was released on 2002-12-31 with total page 778 pages. Available in PDF, EPUB and Kindle. Book excerpt: Covering the whole of Asia and the Pacific region, this text provides both an analytic overview and specific data for each of the 60 countries. Introductory chapters cover regional issues, including: a regional review with the year's trends, developments and key events' analysis of the threat of terrorism in the region; the effects of deflation on the economy; the water crisis and its impact on the poor; and the successes and failures of micro-credit in the region.
Download or read book Fatigue and Fracture Mechanics written by and published by . This book was released on 2001 with total page 796 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Role of Crack Closure Mechanisms on Fatigue Crack Growth of Ti 62222 Under Constant Amplitude and Transient Loading at 54 25 and 175 C written by SG. Berge and published by . This book was released on 1999 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fatigue crack growth behavior of Ti-62222 in sheet form was investigated at three temperatures under various load histories with a specific emphasis on crack opening measurements and mechanisms. Constant-amplitude R = 0.1 near-threshold results showed that based upon applied ?K, fatigue crack growth rates were lower at the two temperature extremes in comparison with those at room temperature. Based upon ?Keff, a moderate temperature effect was observed. The various shifts in the ?Keff curves were a result of different controlling crack closure mechanisms at each temperature. Single tensile overloads at 2.5 x Kmax produced a delay in fatigue crack growth and was most significant at -54°C. Remote crack opening measurements showed no appreciable change during the delay period due to the small region along the crack front that experienced crack closure. Near crack tip opening measured for various combinations of overloads, underloads, and constant ?K at 25°C revealed a general trend for higher near tip opening following a tensile overload. However, a sufficient number of measurements were inconsistent and thus only minimal confidence could be placed with the method. Scanning electron microscopy was used to evaluate surface fatigue crack growth profiles and fatigue crack growth fracture surface morphology.
Download or read book Load Interaction Effects in Ti 62222 at 540C and 1750C for Near threshold and Paris Regime Fatigue Crack Growth written by Shannon Charles Berge and published by . This book was released on 2003 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of Geometry and Load History on Fatigue Crack Growth in Ti 62222 written by RR. Stephens and published by . This book was released on 2000 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fatigue crack growth behavior of Ti-62222 mill-annealed material in sheet form was examined as a function of specimen geometry. The geometries investigated were the eccentrically loaded single edge-notch tension (ESE(T)), the compact tension (C(T)), and the middle tension (M(T)). Tests were conducted at room temperature at two load ratios (R=0.1 and 0.7) and covered a broad range of crack growth rates ranging from 10-7 to 10-2 mm/cycle. The same precracking and threshold test procedures were used for all geometries as each threshold test was started at the same crack length and continuous load shedding was applied at a K-gradient of C=-0.08 mm-1. As a result, the same stress intensity-crack length (K-a) history was maintained throughout all of the threshold tests. Experimental results showed differences in fatigue crack growth behavior at the lowest crack growth rates while higher crack growth rates were similar. Surface roughness differences at lower crack growth rates were observed at the same nominal ?K for the three geometries, suggesting differing crack growth mechanisms. Discrepancies observed in specimen behavior are assessed in terms of the crack tip stress field distribution which include both y-direction and T-stresses. In addition, supplemental fatigue crack growth tests showed a dependence on crack length and load reduction procedure.
Download or read book Load Interaction Effects on Fatigue Crack Growth in Ti 6Al 4V Alloy written by Robert Peh-ying Wei and published by . This book was released on 1973 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: The importance of delay, retardation in the rate of fatigue crack growth, produced by load interactions in variable amplitude loading, on the accurate prediction of fatigue lives of engineering structures is discussed. The effects of a broad range of loading variables on delay in fatigue crack growth at room temperature are examined for a mill annealed Ti-6Al-4V alloy. The results are used to estimate crack growth behavior under programmed loads.
Download or read book Fatigue Crack Growth Under Spectrum Loads written by Ralph Ivan Stephens and published by ASTM International. This book was released on 1976 with total page 345 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Investigation of Fatigue Crack Growth in Ti 8A1 1Mo 1V duplex annealed Specimens Having Various Widths written by C. M. Hudson and published by . This book was released on 1967 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of Load Variables on Fatigue Crack Initiation and Propagation written by D. F. Bryan and published by ASTM International. This book was released on 1980 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fatigue Crack Growth Characteristics of Thin Sheet Titanium Alloy Ti 6 2 2 2 2 written by and published by . This book was released on 2001 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Load and Environment Interactions in Fatigue Crack Growth written by T. T. Shih and published by . This book was released on 1974 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: The influences of environment on delay and on fatigue crack growth under programmed loading were examined for a mill annealed Ti-6Al-4V alloy. Test environments included dehumidified argon, air (with 30-60% relative humidity), distilled water, and 3.5% NaCl solution. The effects of load sequence and block size on fatigue under programmed loads were investigated also. Experimental results show that the mildly aggressive environments (atmospheric moisture and distilled water) have little effect on delay. Salt solution, on the other hand, has a significant effect on delay and on crack growth under programmed loading; the effect on delay being dependent on frequency or hold-time. Both load sequence and block size can significantly alter fatigue life under programmed loading. The need for further fundamental understanding of load and environment interactions in fatigue is discussed. (Modified author abstract).
Download or read book The Effect of Load Excursions on Fatigue Crack Growth in a Titanium Alloy written by David Eugene Lemm and published by . This book was released on 1997 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fatigue Crack Propagation written by and published by . This book was released on 1967 with total page 560 pages. Available in PDF, EPUB and Kindle. Book excerpt:
