Variable Amplitude Fatigue Crack Growth in Titanium Alloy Ti-4Al-4Mo-2Sn-0.5Si (IMI 550). PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Variable Amplitude Fatigue Crack Growth in Titanium Alloy Ti-4Al-4Mo-2Sn-0.5Si (IMI 550). PDF full book. Access full book title Variable Amplitude Fatigue Crack Growth in Titanium Alloy Ti-4Al-4Mo-2Sn-0.5Si (IMI 550). by C. M. Ward-Close. Download full books in PDF and EPUB format.
Author: C. M. Ward-Close Publisher: ISBN: Category : Metallurgy Languages : en Pages : 9
Book Description
A study has been made of fatigue crack growth behaviour in the titanium alloy (Ti-4Al-4Mo-2Sn-0.5Si) (IMI 550)), subject to single tensile overloads and the FALSTAFF flight simulation loading spectrum. Fatigue overloads were found to produce crack growth rate acceleration, followed by delayed retardation. The transient changes in crack growth rates were associated with large changes in crack closure immediately behind the crack tip. For both single overloads and flight simulation loading, the greatest load-interaction effects were at the lowest load amplitudes. Microstructure had only a slight influence on load-interaction effects associated with single tensile overloads. Great Britain. (jes).
Author: C. M. Ward-Close Publisher: ISBN: Category : Metallurgy Languages : en Pages : 9
Book Description
A study has been made of fatigue crack growth behaviour in the titanium alloy (Ti-4Al-4Mo-2Sn-0.5Si) (IMI 550)), subject to single tensile overloads and the FALSTAFF flight simulation loading spectrum. Fatigue overloads were found to produce crack growth rate acceleration, followed by delayed retardation. The transient changes in crack growth rates were associated with large changes in crack closure immediately behind the crack tip. For both single overloads and flight simulation loading, the greatest load-interaction effects were at the lowest load amplitudes. Microstructure had only a slight influence on load-interaction effects associated with single tensile overloads. Great Britain. (jes).
Author: C. M. Ward-Close Publisher: ISBN: Category : Languages : en Pages : 8
Book Description
A study has been made of fatigue crack growth behaviour in the titanium alloy (Ti-4Al-4Mo-2Sn-0.5Si) (IMI 550)), subject to single tensile overloads and the FALSTAFF flight simulation loading spectrum. Fatigue overloads were found to produce crack growth rate acceleration, followed by delayed retardation. The transient changes in crack growth rates were associated with large changes in crack closure immediately behind the crack tip. For both single overloads and flight simulation loading, the greatest load-interaction effects were at the lowest load amplitudes. Microstructure had only a slight influence on load-interaction effects associated with single tensile overloads. Great Britain. (jes).
Author: Robert Peh-ying Wei Publisher: ISBN: Category : Axial loads Languages : en Pages : 36
Book Description
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.
Author: JM. Larsen Publisher: ISBN: Category : Crack closure Languages : en Pages : 13
Book Description
An experimental investigation of load interaction effects in Ti-6Al-2Sn-4Zn-2Mo is presented. Simple variable amplitude loading spectra were applied to test samples, and the crack propagation stress intensity factor, KPR, was subsequently measured. The data were condensed to two equations ("master curves") that describe the influence of an unloading cycle after constant amplitude loading and a single overload cycle, respectively. The results suggest that load interaction effects are caused by residual compressive stresses ahead of the crack front, whereas the influence of crack closure is minor.
Author: C. J. Beevers Publisher: ISBN: Category : Languages : en Pages : 43
Book Description
Fatigue crack growth at intermediate rates and R 0.1 has been measured in compact tension specimens of the alloys Ti-6Al-4V and Ti-6Al-5Zr-0.5Mo-0.25Si. Crack length was determined from the output of a crack mouth displacement gauge and by using a d.c. potential drop technique. The incidence of crack closure was examined during fatigue by using both of the above methods; COD was found to be more reliable for closure measurement than potential drop. In contrast to the fine microstructured Ti-6Al-4V, the coarse Ti-6Al-5Zr-0.5Mo-0.25Si showed substantial load transfer across the crack faces during fatigue and this was attributed to a 'non-closure' mechanism. Low crack growth rates in the latter alloy were rationalized in terms of an effective delta K. Marked reductions in growth rate produced by variable amplitude loading ot Ti-6Al-4V could not be explained by crack closure. (Author).
Author: Publisher: ISBN: Category : Languages : en Pages :
Book Description
A titanium alloy (Ti-6Al-4V STOA) plate material was provided by the University of Dayton Research Institute from a previous U.S. Air Force high-cycle fatigue study. Fatigue-crack-growth tests on compact, C(T), specimens have been previously performed at Mississippi State University on the same material over a wide range in rates from threshold to near fracture for several load ratios (R = Pmin/Pmax). These tests used the compression pre-cracking method to generate fatigue-crack-growth-rate data in the near-threshold regime. Current load-reduction procedures were found to give elevated thresholds compared to compression pre-cracking methods. A crack-closure model was then used to determine crack-front constraint and a plasticity-corrected effective stress-intensity-factor-range relation over a wide range in rates and load ratios. Some engineering estimates were made for extremely slow rates (small-crack behavior), below the commonly defined threshold rate. Single-edge-notch-bend, SEN(B), fatigue specimens were machined from titanium alloy plates and were fatigue tested at two constant-amplitude load ratios (R = 0.1 and 0.5) and a modified Cold-Turbistan engine spectrum. Calculated fatigue lives from FASTRAN, a fatigue-life-prediction code, using small-crack theory with an equivalent-initial-flaw-size (semi-circular surface flaw) of 9 æm in radius at the center of the semi-circular edge notch fit the constant-amplitude test data fairly well, but underpredicted the spectrum loading results by about a factor of 2 to 3. Life predictions made with linear-cumulative damage (LCD) calculations agreed fairly well with the spectrum tests.
Author: National Aeronautics and Space Adm Nasa Publisher: Independently Published ISBN: 9781723951589 Category : Science Languages : en Pages : 76
Book Description
Fatigue crack growth rates of Ti 6-2-2-2-2 as a function of stress ratio, temperature (24 or 177 C), tensile orientation and environment (laboratory air or ultrahigh vacuum) are presented. Fatigue crack growth rates of Ti 6-2-2-2-2 are also compared with two more widely used titanium alloys (Timetal 21S and Ti 6Al-4V). The fatigue crack growth rate (da/dN) of Ti 6-2-2-2-2 in laboratory air is dependent upon stress ratio (R), particularly in the near-threshold and lower-Paris regimes. For low R (less than approximately 0.5), da/dN is influenced by crack closure behavior. At higher R (> 0.5), a maximum stress-intensity factor (K(sub max)) dependence is observed. Fatigue crack growth behavior is affected by test temperature between 24 and 177 C. For moderate to high applied cyclic-stress-intensity factors (delta-K), the slope of the log da/dN versus log delta-K curve is lower in 177 C laboratory air than 24 C laboratory air. The difference in slope results in lower values of da/dN for exposure to 177 C laboratory air compared to room temperature laboratory air. The onset of this temperature effect is dependent upon the applied R. This temperature effect has not been observed in ultrahigh vacuum. Specimen orientation has been shown to affect the slope of the log da/dN versus log delta-K curve in the Paris regime.Smith, Stephen W. and Piascik, Robert S.Langley Research CenterCRACK PROPAGATION; FATIGUE (MATERIALS); TITANIUM ALLOYS; CORROSION; STRESS RATIO; TEMPERATURE EFFECTS; CRACK CLOSURE; STRESS INTENSITY FACTORS
Author: C. M. Ward-Close
Author: C. M. Ward-Close
Author: C. M. Ward-Close
Author: Andrew Leigh Veit
Author: Robert Peh-ying Wei
Author: JM. Larsen
Author: C. J. Beevers
Author: Christopher J. Cousins
Author: 
Author: 
Author: National Aeronautics and Space Adm Nasa