Download or read book Deformation and Solid Solution Strengthening of Titanium Aluminum Single Crystals written by N. E. Paton and published by . This book was released on 1976 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: Solid solution strengthening and deformation behavior of titanium-aluminum single crystals has been studied over the range of temperature 77-1100K and from 0 to 6.6 w/o Al. Crystal orientations have been chosen to promote prism slip, basal slip and c+a slip, and the temperature and composition dependence of the critical resolved shear stress (CRSS) for each of these slip systems has been determined. Although prism slip has the lowest CRSS of all the slip systems studied, both increasing temperature and Al concentration make the stresses for prism and basal slip converge. Deformation with a c+a slip vector is always more difficult to activate than either basal or prism slip with an a slip vector, and this resulted in fracture of crystals oriented for c+a slip by unstable shear, under certain conditions. In addition to the work on the deformation of Ti-Al crystals in compression, some studies were conducted on both creep and cyclic deformation (fatigue) of single crystals. The impact of these studies on understanding of deformation texture development and the use of textured titanium alloys in structures is briefly discussed. (Author).
Download or read book Research on Deformation and Possible Strengthening Mechanisms for Solid Solution Phases of Titanium written by Thomas R. Cass and published by . This book was released on 1969 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: The report is a summary of research on the growth, perfection and slip processes in pure titanium and titanium-aluminum single phase alloys. A technique was developed for the growth of titanium and dilute titanium alloy single crystals using an electron-beam zone refiner. A dislocation etchant was discovered, allowing the perfection of these crystals of 10 to the minus 9th power/sq cm. However, annealing the crystals just below the transformation temperature for long times lowers the dislocation density by two to three orders of magnitude. Compression specimens were spark-erosion machined from single crystals, annealed and mecahnically tested. A c-axis compression specimen of high purity titanium deformed by twinning. However, high interstitial content and dilute aluminum alloys both deformed by c+a glide when the load axis was near (0001). This additional deformed system accounts for the polycrystalline ductility of alpha-titanium alloys. An analysis of plastic deformation modes in TiAl was also made. Results on polycrystalline TiAl were in agreement with these predictions. However, single crystals could not be grown for definitive verification of the hypothesized modes. (Author).
Download or read book Deformation and Solid Solution Strengthening of Ti V Alloys written by R. G. Baggerly and published by . This book was released on 1973 with total page 35 pages. Available in PDF, EPUB and Kindle. Book excerpt: The deformation and aging characteristics of Ti-V alloys and Ti-12 1/2 w/o Mo alloy were investigated. Single crystals of Ti-30V, Ti-40V and Ti-12 1/2 Mo were used to study deformation behavior for the solid solution condition and after an aging treatment. The critical resolved shear stress for slip or twinning was determined as a function of temperature for these crystals. Optical trace analysis was used to identify the active slip or twinning plane and thin foil electron microscopy was used to identify aging products. X-ray precession camera techniques were occasionally used to corroborate results. Tests were also conducted to determine the effect of grain size on yield stress and work hardening behavior in Ti-20V, Ti-30V, and Ti-40V alloys.
Download or read book Deformation and Solid Solution Strengthening of BCC Titanium Vanadium Alloys written by N. E. Paton and published by . This book was released on 1974 with total page 31 pages. Available in PDF, EPUB and Kindle. Book excerpt: The influence of oxygen on the strength and deformation behavior of Ti-40V single crystals containing various amounts of oxygen has been examined. The flow stress has been analytically separated into a thermally activated component (tau*) and an athermal component (tau sub mu). It is shown that tau* increases linearly with oxygen concentration (C), whereas tau sub mu increases as C to the 1/2 power. Oxygen also tends to reduce the tendency for planar slip by enhancing cross slip. The implications of these effects on the properties of bcc Ti alloys are discussed. (Author).
Download or read book Deformation and Solid Solution Strengthening of BCC Titanium Molybdenum Alloys written by R. G. Baggerly and published by . This book was released on 1974 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: The deformation and strengthening of bcc Ti-Mo alloys has been investigated by examining single crystals of Ti-12-1/2 wt.% Mo. A change in deformation mode from twinning to slip occurs when single phase crystals are aged to precipitate omega phase. In the single phase solution treated condition, the crystals deform by (332) 113 twinning. When omega phase is present the crystals deform by 111 slip. The occurrence and formation of alpha phase in Ti-Mo-Al alloys has also been investigated. The relationship between Burgers and non-Burgers alpha phase is discussed with regard to mechanisms of formation and kinetics of the transformation. (Author).
Download or read book Proceedings of the 13th World Conference on Titanium written by Vasisht Venkatesh and published by John Wiley & Sons. This book was released on 2016-04-26 with total page 4024 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains the Proceedings of the 13th World Conference on Titanium.
Download or read book Solid solution Strengthening of Dilute Single Crystal Aluminum Alloys Oriented for Multiple Slip written by Jin-Hoon Cho and published by . This book was released on 1993 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1982 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Download or read book An Introductory Guide to EC Competition Law and Practice written by Valentine Korah and published by . This book was released on 1994 with total page 2354 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effects of Slip Character and Crack Closure on the Growth of Small Fatigue Cracks in Titanium aluminium Alloys written by James M. Larsen and published by . This book was released on 1990 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt: An investigation was performed to study the effects of slip character and crack closure on the propagation of small fatigue cracks in titanium- aluminum alloys. The materials examined were solution-treated Ti-4Al and Ti-8Al, as well as aged Ti-8Al. The propagation of naturally initiated surface cracks of depths as small as 25 micrometers was compared with the behavior of large through-thickness cracks. An extensometer was used to monitor crack closure throughout the large crack tests, and the closure behavior of the small cracks was measured using a computerized laser interferometric displacement gage having a displacement resolution of 0.01 micrometer. The measurements of crack closure were used to compute an effective stress intensity factor range. In all three alloys and for all test conditions, which included a range of stress levels and stress ratios, small cracks propagated faster than large cracks subjected to an equivalent Delta K, and the small cracks propagated under conditions that were significantly below the large-crack threshold, Delta K(th). Although the character and distribution of slip in Ti-Al alloys may have a dramatic influence on fatigue crack initiation and on the propagation of large cracks, this effect was minimal for small cracks.
Download or read book Strength Deformation Modes and Fracture in Titanium aluminum Alloys written by M. J. Blackburn and published by . This book was released on 1969 with total page 45 pages. Available in PDF, EPUB and Kindle. Book excerpt: The variation of yield strength, deformation modes and fracture characteristics of titanium:aluminum alloys containing up to 25% aluminum were studied. This composition range includes three phase fields based on hexagonal phases, a solid solution, and ordered phase based on the composition Ti3Al and a two phase region. An attempt is made to account for the factors that control the strength and fracture characteristics of these alloys. (Author).
Download or read book Physics of Solid Solution Strengthening written by E. Collings and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is the proceedings of a Symposium entitled "The Physics of Solid-Solution Strengthening in Alloys" which was held at McCormick Place, Chicago, on October 2, 1973, in association with a joint meeting of the American Society for Metals (ASM) and The Metallurgical Society (TMS) of the American Institute of Mining, Metallurgical, and Petroleum Engineers (AIME). The symposium, which was initiated and organized by the editors of this volume, was sponsored by the Committee on Alloy Phases, Institute of Metals Division, TMS, AIME, and the Flow and Fracture Section of the Materials Science Division, ASM. The discipline of Alloy Design has been very active in recent years, during which considerable stress has been placed on the roles of crystallography and microstructure in the rationalization and prediction of properties. Underestimated as a component of alloy design, however, has been the importance of physical property studies, even though physical property measurements have tradi tionally been employed to augment direct or x-ray observations in the determination of phase equilibrium (and, indeed, metastable equilibrium) boundaries.
Download or read book Aerospace Materials and Material Technologies written by N. Eswara Prasad and published by Springer. This book was released on 2016-11-11 with total page 594 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a comprehensive compilation of chapters on materials (both established and evolving) and material technologies that are important for aerospace systems. It considers aerospace materials in three Parts. Part I covers Metallic Materials (Mg, Al, Al-Li, Ti, aero steels, Ni, intermetallics, bronzes and Nb alloys); Part II deals with Composites (GLARE, PMCs, CMCs and Carbon based CMCs); and Part III considers Special Materials. This compilation has ensured that no important aerospace material system is ignored. Emphasis is laid in each chapter on the underlying scientific principles as well as basic and fundamental mechanisms leading to processing, characterization, property evaluation and applications. This book will be useful to students, researchers and professionals working in the domain of aerospace materials.
Download or read book Investigations to Understand the Deformation and Strengthening Mechanisms of the Solid Solution Phases of Titanium written by R. L. Jones and published by . This book was released on 1968 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mechanical properties data are reported for alpha-titanium of four impurity contents and various grain sizes, tested in the temperature range 4.2K to 800K. Dislocation substructures produced by deformation of commercial purity and high purity alpha-titanium at room temperature were examined by transmission electron microscopy and representative examples are presented and discussed. Work hardening behavior is connected with long-range interactions and is modified by both purity and grain size as well as temperature. The effect of impurity content appears to be related to the degree to which dislocations are restricted to their slip planes. Grain size also influences the yield and flow stresses, the relations observed being approximately of the Hall-Tetch type. The effects of grain size are shown to be athermal in nature and are accounted for in terms of work hardening model. Thermal activation analysis is used to show that the behavior reported is in agreement with the concept that the rate controlling process for low temperature deformation is thermally activated dislocation glide on first order prism planes over barriers associated with individual interstitial impurity atoms. The analysis shows that the nature of barriers is the same in all four materials and that the rate controlling process is unaffected by either grain size or plastic strain. (Author).
Download or read book Tensile Properties to 650 C and Deformation Structures in a Precipitation strengthened Titanium aluminum Alloy written by Madan G. Mendiratta and published by . This book was released on 1973 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: Appreciable strength levels were retained to 650 C in a Ti-10Al-1Si alloy aged in the (alpha alpha sub 2) phase field to yield optimum room temperature strength and ductility. The aging treatment precipitated a uniform distribution of alpha sub 2-particles such that, at room temperature, dislocations bypassed instead of shearing the particles at low strains. Specimens fractured at room temperature exhibited fine uniform dimples even for those aging conditions that imparted no macroscopic ductility. The main crack appeared to propagate through the planar slip bands that had cut through the alpha sub 2-particles. A two-step aging process produced a higher volume fraction of bimodally distributed alpha sub 2-particles that led to higher strength levels at elevated temperatures. Both for the single size and the bimodal alpha sub 2-particle distributions, elevated-temperature deformation structures consisted mainly of planar slip bands that sheared through the alpha sub 2-particles.
Download or read book Solid Solution Strengthening and Dispersion Hardening in Dilute Titanium Alloys written by Takeo Sakai and published by . This book was released on 1973 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of the research was to determine the effect of aluminum on the fundamental mechanical properties of titanium and how such changes are related to the emergence of aluminum as the principal alloying element for titanium. A clearer understanding of the role of aluminum in enhancing the engineering mechanical properties of titanium, it is hoped, would point the way toward development of improved alloys. The report concludes with a discussion of the results from this point of view.
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1975-04 with total page 1082 pages. Available in PDF, EPUB and Kindle. Book excerpt:
