Download or read book Fatigue Crack Growth Characteristics of Thin Sheet Titanium Alloy Ti 6 2 2 2 2 written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-05-31 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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

Download or read book Simulator Study of Stall post stall Characteristics of a Fighter Airplane with Relaxed Longitudinal Static Stability written by and published by . This book was released on 1979 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Parametric Study of the Aerodynamic Characteristics of Nose cylinder flare Bodies at a Mach Number of 6 0 written by George C. Ashby and published by . This book was released on 1965 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Summary of Flight test Results of the VZ 2 Tilt wing Aircraft written by Robert J. Pegg and published by . This book was released on 1962 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Effect of O2 H2o and N2 on the Fatigue Crack Growth Behavior of an Alpha Beta Titanium Alloy at 24 C and 177 C written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-09-17 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: To study the effects of atmospheric species on the fatigue crack growth behavior of an a+B titanium alloy (Ti 6-2-2-2-2) at room temperature and 177 C, fatigue tests were performed in laboratory air, ultrahigh vacuum, and high purity water vapor, oxygen, nitrogen and helium at various partial pressures. Accelerated fatigue crack growth rates in laboratory air compared to ultrahigh vacuum are linked to the damaging effects of both water vapor and oxygen. Observations of the fatigue crack growth behavior in ultrahigh purity environments, along with surface film analysis using X-ray photoelectron spectroscopy (XPS), suggest that multiple crack-tip processes govern the damaging effects of air. Three possible mechanisms are proposed: 1) at low pressure (less than 10(exp -1) Pa), accelerated da/dN is likely due to monolayer adsorption on crack-tip surfaces presumably resulting in decreased bond strengths at the fatigue crack tip, 2) for pressures greater than 10(exp -1) Pa, accelerated da/dN in oxygen may result from oxidation at the crack tip limiting reversible slip, and 3) in water vapor, absorption of atomic hydrogen at the reactive crack tip resulting in process zone embrittlement.Smith, Stephen W. and Piascik, Robert S.Langley Research CenterFATIGUE TESTS; FATIGUE (MATERIALS); CRACK PROPAGATION; TITANIUM ALLOYS; EMBRITTLEMENT; ATMOSPHERIC COMPOSITION; X RAY SPECTROSCOPY; WATER VAPOR; ULTRAHIGH VACUUM; PHOTOELECTRON SPECTROSCOPY

Download or read book Buckling of a Pressurized Toroidal Ring Under Uniform External Loading written by George E. Weeks 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 Investigation of Engine exhaust airframe Interference on a Cruise Vehicle at Mach 6 written by James M. Cubbage and published by . This book was released on 1971 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: Results from an investigation of the effects of underexpanded engine exhaust flow on the aerodynamic performance and stability of a cruise airplane at Mach 6 are presented. The influence of wing reflex angle and nozzle geometry on exhaust flow interference effects was investigated on a flat-plate model. The experiments were conducted at a free-stream Reynolds number of 17.05 X 10 (to the 6 power) based on the length of the airplane model over a model angle-of-attack range of 0(degrees) to 10(degrees) and at nozzle static-pressure ratios from 1 to approximately 4.

Download or read book Analysis of Partly Wrinkled Membranes written by Manuel Stein and published by . This book was released on 1961 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Theory for Inflated Thin wall Cylindrical Beams written by W. B. Fichter and published by . This book was released on 1966 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Loads and Deformations of Buckled Rectangular Plates written by Manuel Stein and published by . This book was released on 1960 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Manned machine Space Station Construction Concept written by Martin M. Mikulas and published by . This book was released on 1984 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Control Integration Concept for Hypersonic Cruise turn Maneuvers written by David L. Raney and published by . This book was released on 1992 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Stagnation point Heat transfer Rate Predictions at Aeroassist Flight Conditions written by Roop N. Gupta and published by . This book was released on 1992 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Transport Methods and Interactions for Space Radiations written by and published by . This book was released on 1991 with total page 624 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Wind Tunnel Investigation of the Interaction and Breakdown Characteristics of Slender wing Vortices at Subsonic Transonic and Supersonic Speeds written by Gary E. Erickson and published by . This book was released on 1991 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Special Course on Aircraft Dynamics at High Angles of Attack Experiments and Modelling written by North Atlantic Treaty Organization. Advisory Group for Aerospace Research and Development. Fluid Dynamics Panel. Special Course and published by . This book was released on 1991 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This report consists of lecture notes of an AGARD Fluid Dynamics Panel Special Course. These notes provide the latest information on the development and use of dynamic experiments in wind tunnels from several of the NATO nations. They address current oscillatory and rotary test techniques, experimental results for typical configurations, and the use of these data for flight mechanics applications. Subject included are: dynamic lift, wing rock, fluid dynamics of rotary flows, mathematical modelling, non-linear data representation, vortex manipulation for control enhancement, and correlations of predictions based on rotary and oscillatory wind-tunnel and flight-test results. The complete course notes are contained in two volumes. The main part of the notes is contained in AGARD Advisory Report 265 (ADA235179). The present volume includes papers on: Unsteady aerodynamics of slender wings; Dynamic stall effects and applications to high performance aircraft; Oscillatory test techniques; Large amplitude oscillations; Oscillatory data for typical configurations; and Forebody vortex control."--Stinet.

Download or read book Extended Study of Flaw Growth at Fastener Holes written by T. M. Hsu and published by . This book was released on 1978 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: An analytical and experimental investigation was conducted to characterize the fracture and cyclic-growth behavior of cracks emanating from various types of fastener holes, such as open, close-tolerance, interference- fit, and cold-worked fastener holes. An analytical approach was developed for estimating stress intensity factors for through cracks emanating from these types of fastener holes. Approximate stress intensity factors for quarter- elliptical cracks emanating from a corner of the same types of fastener holes were derived from corresponding through-crack solutions. Two alloy plates (2219- T851 aluminum and 6Al-4V (ELI) beta annealed titanium) with and without intentional initial flaws were tested under constant amplitude cyclic load and flight-by-flight fighter and bomber spectrum loads. Two initial flaw shapes corresponding to a quarter-circular corner crack and a through-the-thickness crack and three initial crack lengths (small, intermediate and large) were used in the test program. Three levels of cold working and interference and one level of fastener load transfer were included for each alloy. The amount of load transferred through the loaded fastener was maintained uniformly at the level which produced a bearing stress equal to the far-field stress. Correlations between calculated stress intensities and those reduced from fatigue crack growth data were good, except for very small cracks growing from the cold-worked holes. Also, the natural cracks initiated in the fatigue tests were most commonly corner and embedded types whose shapes corresponded quite closely to the quarter- and semi-elliptical shapes used in the analyses.