Download or read book Thermal Mechanical Fatigue Crack Growth in Titanium Alloys written by J. Dai and published by . This book was released on 1996 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: Strain controlled thermal-mechanical fatigue crack growth (TMFCG) tests were conducted on two titanium alloys, namely Ti-6A1-4V and Ti-6Al-2Sn-4Zr-6Mo, to evaluate the effect of phase angle between strain and temperature on the TMFCG rates. Three fracture mechanics parameters were used to correlate the data: the ?K, ?Ke and ?Keff. A fractographic study of the specimens tested under TMF was carried-out to identify the mechanisms responsible for cracking in these two titanium alloys. Hence, specimens tested under in-phase (?max at Tmax), out-of-phase (?min at Tmax) and counter-clockwise diamond (90° out-of-phase) conditions were compared to specimens tested under isothermal conditions (Tmin and Tmax) for different ?Keff levels. The dominant TMF cracking mechanisms were mechanical fatigue (crack tip plasticity) and oxygen-induced embrittlement. The ?Keff was found to be the only parameter to properly correlate all the data obtained under various testing conditions. A model is developed to predict the TMFCG rates based solely on isothermal data. The model uses a linear summation of the contributions to crack growth of the two dominant mechanisms which are active at the minimum and maximum temperature of the cycle. A discussion on the applicability of the model to predict the fatigue lives of actual components is discussed.
Download or read book Crack Growth of a Titanium Aluminide Alloy Under Thermal Mechanical Fatigue written by David G. Burgess and published by . This book was released on 1988 with total page 111 pages. Available in PDF, EPUB and Kindle. Book excerpt: New materials must be developed in order to increase the operating temperature of Air Force gas turbines. One of the materials under consideration is a titanium-aluminide alloy, Ti3Al1. Before this material can be used, its behavior under combined thermal-mechanical fatigue (TMF) conditions must be understood. To understand this behavior, three 315-649 C TMF test and one 649 C isothermal fatigue test with load hold time were conducted. Crack growth data from these tests were compared with each other as well as with crack growth data from four previous TMF and isothermal fatigue tests of the same material. Keywords: Metal fatigue; Crack propagation; Fracture mechanics; Physical metallurgy. (kt/jes).
Download or read book Thermomechanical fatigue behavior of materials written by Michael J. Verrilli and published by ASTM International. This book was released on 1996 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Crack Growth of a Titanium Aluminide Alloy Under Thermal Mechanical Fatigue written by David G. Burgess (CAPT, USAF.) and published by . This book was released on 1988 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fatigue Crack Growth Measurements in TMF Testing of Titanium Alloys Using an ACPD Technique written by Y. Dai and published by . This book was released on 1995 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: A thermal-mechanical fatigue (TMF) testing system has been developed which is capable of studying the fatigue behaviors of gas turbine materials under simultaneous changes of temperatures and strains (or stresses). Furthermore, an advanced alternating current potential difference (ACPD) measurement technique has been developed successfully to perform on-line monitoring of fatigue crack initiation and growth in specimens tested under isothermal and TMF conditions. In this paper, the basic principles of the ACPD technique as well as all the relevant experimental procedures for performing ACPD measurements, including probe setup, choice of alternating currents (AC) and frequencies, noise rejection, data acquisition, and signal processing, are described. The linear relationship between ACPD signals and crack lengths, as well as the effects of thermal cycling on the ACPD signal, are presented and discussed. The capabilities of the TMF and ACPD systems are well illustrated by fatigue crack initiation and growth test results under isothermal and TMF conditions. These tests were performed on two titanium forgings, Ti-6Al-4V (Ti64) and Ti-6Al-2Sn-6Mo (Ti6246), respectively. Alloy Ti64 was TMF cycled between 150 and 400°C, while Ti6246 was cycled between 200 and 482°C. The resolution for detecting crack initiation at the root of notches was found to be 50 ?m with 95% confidence while the resolution for crack growth was 2 ?m per mV change of ACPD. An environmental assisted cracking model applied to TMF crack growth is proposed for rationalizing the data.
Download or read book Fatigue of Beta Processed and Beta Heat treated Titanium Alloys written by Russell Wanhill and published by Springer Science & Business Media. This book was released on 2011-10-28 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt: This publication reviews most of the available literature on the fatigue properties of β annealed Ti-6Al-4V and titanium alloys with similar microstructures. The focus is on β processed and β heat-treated alloys because β annealed Ti-6Al-4V has been selected for highly loaded and fatigue-critical structures, including the main wing-carry-through bulkheads and vertical tail stubs, of advanced high-performance military aircraft. An important aspect of the review is a concise survey of fatigue life assessment methods and the required types of fatigue data. This survey provides the background to recommendations for further research, especially on the fatigue behaviour of β annealed Ti-6Al-4V under realistic fatigue load histories, including the essential topic of short/small fatigue crack growth. Such research is required for independent fatigue life assessments that conform to the aircraft manufacturer’s design requirements, and also for life reassessments that most probably will have to be made during the service life of the aircraft.
Download or read book Crack Growth Rate Modeling of a Titanium aluminide Alloy Under Thermal mechanical Cycling written by John J. Pernot and published by . This book was released on 1991 with total page 606 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fatigue crack Propagation in Several Titanium and Stainless steel Alloys and One Superalloy written by C. M. Hudson and published by . This book was released on 1964 with total page 40 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 Thermo mechanical Fatigue Behavior of Materials written by Huseyin Sehitoglu and published by ASTM International. This book was released on 2000 with total page 339 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Titanium written by Matthew J. Donachie and published by ASM International. This book was released on 2000 with total page 381 pages. Available in PDF, EPUB and Kindle. Book excerpt: Designed to support the need of engineering, management, and other professionals for information on titanium by providing an overview of the major topics, this book provides a concise summary of the most useful information required to understand titanium and its alloys. The author provides a review of the significant features of the metallurgy and application of titanium and its alloys. All technical aspects of the use of titanium are covered, with sufficient metals property data for most users. Because of its unique density, corrosion resistance, and relative strength advantages over competing materials such as aluminum, steels, and superalloys, titanium has found a niche in many industries. Much of this use has occurred through military research, and subsequent applications in aircraft, of gas turbine engines, although more recent use features replacement joints, golf clubs, and bicycles.Contents include: A primer on titanium and its alloys, Introduction to selection of titanium alloys, Understanding titanium's metallurgy and mill products, Forging and forming, Castings, Powder metallurgy, Heat treating, Joining technology and practice, Machining, Cleaning and finishing, Structure/processing/property relationships, Corrosion resistance, Advanced alloys and future directions, Appendices: Summary table of titanium alloys, Titanium alloy datasheets, Cross-reference to titanium alloys, Listing of selected specification and standardization organizations, Selected manufacturers, suppliers, services, Corrosion data, Machining data.
Download or read book Toughness and Fracture Behavior of Titanium written by R. G. Broadwell and published by ASTM International. This book was released on 1978 with total page 306 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 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 Fatigue Crack Growth Behavior of Two Titanium Alloys at Room and Elevated Temperature written by Todd P. Albertson and published by . This book was released on 1996 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Thermomechanical Fatigue Behavior of Materials written by Michael A. McGaw and published by ASTM International. This book was released on 2003 with total page 330 pages. Available in PDF, EPUB and Kindle. Book excerpt: "ASTM Stock Number: STP1428. - "Fourth Symposium on Thermomechanical Fatigue Behavior of Materials, held in Dallas, Texas on November 7-8, 2001. The Symposium was sponsored by ASTM Committee E08 on Fatigue and Fracture and its Subcommittee E08.05 on Cyclic Deformation and Fat. - Includes bibliographical references and indexes. ASTM International; 2011.
Download or read book Accelerated Crack Propagation of Titanium by Methanol Halogenated Hydrocarbons and Other Solutions written by and published by . This book was released on 1967 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fatigue Crack Propagation in Metastable Titanium Alloys written by A. Raith and published by . This book was released on 1984 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt: The fatigue crack growth rate tests of water quenched Corona-5 (Ti-4.5Al-1.5Cr-5Mo) and Ti-6Al-4V alloy were conducted in air at room temperature. The effect of the presence of the metastable retained beta phase on the fatigue crack growth rate was examined in this research. The specimens were heat treated and water quenched to have unstable beta phase that could be transformed to martensite during the fatigue crack growth testing. As quenched specimens were compared with specimens in the mill annealed condition. The fatigue crack growth rates of all the specimens were in the same order of magnitude regardless of the heat treatment. From this research it was shown that in Corona-5 and Ti-6Al-4V alloys the fatigue crack growth rates were not affected by the strain induced martensitic transformation.
