Download or read book Observations on the effect of temperature rise at fracture in two titanium alloys written by Heinz G. F. Wilsdorf and published by . This book was released on 1986 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1974 with total page 938 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Investigation of Titanium Alloy Fracture Upon Rolling written by I. M. Pavlov and published by . This book was released on 1969 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: Titanium alloys (single-phase alpha-alloy VT1, complex-alloyed alpha-alloy ST1, two-phase alloys OT4, VT6S, VT14, and single-phase beta alloy VT15) always fracture on rolling at 500-800C. Bands, similar to macrolocalized strain bands in steel, and cracks are formed by the rolling. The microhardness of these bands, exceeding that of the basic metal, cannot be explained by single strain hardening. The formation of these bands in titanium alloys is attributed to phase transformations in the local heating sites under action of the heat effect. The local overheating causes low heat conductivity in the titanium alloys and more rapid deformation upon rolling. This belief is supported, for instance, by the increased heat effect and increased microhardness observed in VT14 on rolling at the lower temperatures. The structure of the bands, which are arranged diagonally to the cross section of the macrosections, differs from that of the base metal. In addition there are fine bands, also arranged at about 45 degrees to the sample surface. The use of fractional deformations instead of the large deformations usually encountered in thermomechanical treatment is recommended to reduce the probability of forming these bands and microcracks. (Author).
Download or read book The investigation of the fracture of titanium alloys by in situ and analytical microstructural techniques written by Heinz G. F. Wilsdorf and published by . This book was released on 1988 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt: To study the effects of microstructures on crack propagation in titanium and titanium alloys was the prime objective of this project. The initial phase consisted of producing and characterizing microstructures in Ti-8Mn and in Ti-10V-2Fe-3Al. Other preliminary work was concerned with a determination of void initiation sites in C.P. titanium. The discovery that fracture surfaces exhibited limited areas with unusual dimple features, interpreted to have been caused by high temperatures, led to research on the temperature rise of moving crack tips. Experimentally, this entailed mechanical measurements using strain rates, the determination of stress intensity rates, straining in vacuum, measurement of fracture topographies by stereophotogrammetry, and the recording of light emission during fracture. Keywords: Polycrystalline titanium, Titanium alloys, Manganese alloys, Iron, Aluminum. (jes).
Download or read book Fracture Toughness Behavior of Unaged Beta III Titanium written by HJ. Rack and published by . This book was released on 1978 with total page 21 pages. Available in PDF, EPUB and Kindle. Book excerpt: The dynamic fracture toughness behavior of unaged Beta-III (Ti-10.2 Mo-6Zr-4.5Mo) titanium has been investigated. Both solution treatment practice and subsequent test temperature have been found to affect the fracture toughness. Decreasing the solution treatment temperature from 1255 to 1005 K generally led to a decrease in the fracture toughness over the entire range of test temperatures investigated. In addition, decreasing the test temperature from 473 to 77 K also resulted in lower fracture toughness. These reductions in fracture toughness have been shown to be related to the introduction of increasing amounts of a localized shear fracture mode with both decreasing solution and test temperature. Based on these observations, a model has been proposed which describes the stress/strain conditions at the tip of a propagating crack that appear to enhance shear fracture. Finally, it has been suggested that the principal metallurgical variable controlling the choice of fracture mode transition from either dimple to cleavage or dimple to shear dimple in unaged metastable ? titanium alloys is the primary deformation mechanism. Twinning tends to promote shear instability while slip may be associated with low temperature cleavage crack propagation.
Download or read book Correlation of Two Fracture Toughness Tests for Titanium and Ferrous Alloys written by Charles N. Freed and published by . This book was released on 1969 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: High-strength ferrous and titanium alloys are of interest for use in complex structures; a knowledge of the notch fracture toughness of these alloys is necessary to preclude catastrophic failure. A previously established relationship between the dynamic tear test energy and the explosion tear test performance provides reliable fracture-toughness information of those alloys characterized by a toughness level requiring plastic deformation to propagate fracture. This analysis has not been extended to the ultrahigh-strength alloys in which fracture can propagate castastrophically at elastic stress levels. For these alloys, the analytical methods of linear elastic fracture mechanics provide the required elastic stress level and flaw-size relationship for fracture. This report deals with a 'marriage' of the two approaches-the engineering and the analytical-by correlative techniques. (Author).
Download or read book Metallurgical Applications of Shock Wave and High Strain Rate Phenomena written by Murr and published by CRC Press. This book was released on 1986-06-06 with total page 1134 pages. Available in PDF, EPUB and Kindle. Book excerpt: Emphasizing metallurgical and materials applications of shock-wave and high-strain-rate phenomena, this superb volume presents the work of the leading international authorities who examine the state of the art of explosive and related technologies in the context of metallurgical and materials processing and fabrication.
Download or read book Deformation of Dual Phase Titanium Alloys written by Jikang Zhong and published by . This book was released on 2012 with total page 458 pages. Available in PDF, EPUB and Kindle. Book excerpt: The deformation behaviour of dual phase titanium alloys has been investigated using experimental and modelling methods. The motivation for conducting this investigation was to improve understanding of the deformation behaviour of dual phase titanium alloys in order to contribute to the long term goal of reducing manufacturing cost and improving production efficiency. Dual phase titanium alloys have been studied under two deformation conditions: high speed machining and uniaxial compression, which represent respectively high rate and low rate deformation. The microstructure and texture of the serrated chips obtained during high speed cutting of the dual phase Ti-6Al-4V alloy have been studied. The cutting speed, depth of cut and the orientation of the sample were found to have a significant influence on the deformation of serrated chips. Adiabatic shear bands were found in the serrated chips due to non-uniform deformation of Ti-6Al-4V alloy and deformation heating. In addition, there is reasonable agreement between the predicted texture using the visco-plastic self-consistent (VPSC) model and the measured texture using the electron backscatter diffraction (EBSD) technique indicating that the deformation in an adiabatic shear band is due to shear.The deformation behaviour of dual phase Ti-Mn alloys has been characterised with uniaxial compression at different temperatures and strain rates. The flow stress plateau phenomenon was observed in all the Ti-Mn alloys in the low to medium temperature range (27~500°C), which is attributed to the occurrence of dynamic strain aging (DSA). The flow softening behaviour was observed in dual phase Ti-Mn alloys in the high to sub-transus temperature range (600~800°C), which is attributed to the change in volume fraction of [beta] phase during deformation due to the rise in temperature caused by deformation heating. The yield point phenomenon was observed when the Ti-Mn alloys are above their [beta] transus temperatures. This phenomenon has been attributed to the multiplication of dislocations at the beginning of plastic deformation and dynamic recovery in the following plastic deformation. The strain rate sensitivity of Ti-Mn alloys was low in the low to medium temperature range and thus the effect of strain rate on deformation is not obvious. However, it was high in the high to sub-transus temperature range and thus the effect of strain rate on the deformation is significant. The 0.2% proof stress was found to increase with the volume fraction of [beta] phase. The strain rate sensitivity was found to decrease with the volume fraction of [beta] phase in the low to medium temperature range because the strain rate sensitivity of the [alpha] phase is higher than the [beta] phase. However, the strain rate sensitivity was found to increase with the volume fraction of [beta] phase at high temperatures because the strain rate sensitivity of the [beta] phase becomes larger than the [alpha] phase. A considerable temperature rise was observed during compression of the Ti-Mn alloys and this indicates that the effect of deformation heating on deformation is not negligible. A composite model has been constructed to predict the plastic stress-strain curves of the dual phase Ti-Mn alloys using the in-situ behaviour of the component phases. The partition of stress and strain between the component phases has been accounted for by using three partitioning assumptions: iso-strain, iso-stress and iso-work. There was good agreement between the predicted curves and the experimental curves. It was found that the in-situ behaviour of the [alpha] phase is different in different dual phase Ti-Mn alloys and it exhibits a linear relationship with the volume fraction of [beta] phase when the dominant matrix is the same. The modelling results in the low to medium temperature range indicate that most of the plastic deformation occurs in the localised shear band, which is consistent with the experimental observation that the dual phase Ti-Mn alloys were more susceptible to the formation of localised shear bands. In addition, it was found that a change in the dominant matrix in dual phase Ti-Mn alloys significantly influences the in-situ behaviour of the [alpha] phase. The modelling results in the high to sub-transus temperature range indicate that the flow softening behaviour observed in dual phase Ti-Mn alloys is related to the change in volume fraction of the [beta] phase and the diffusion of Mn during the deformation.
Download or read book Physics Briefs written by and published by . This book was released on 1994 with total page 916 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 1995 with total page 602 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 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:
Download or read book ERDA Energy Research Abstracts written by United States. Energy Research and Development Administration and published by . This book was released on 1977 with total page 776 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book ERDA Energy Research Abstracts written by United States. Energy Research and Development Administration. Technical Information Center and published by . This book was released on 1977 with total page 1680 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Titanium Alloys written by Jan Sieniawski and published by BoD – Books on Demand. This book was released on 2013-05-15 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book contains six chapters and covers topics dealing with biomedical applications of titanium alloys, surface treatment, relationships between microstructure and mechanical and technological properties, and the effect of radiation on the structure of the titanium alloys.
Download or read book Handbook of Workability and Process Design written by George E. Dieter and published by ASM International. This book was released on 2003-01-01 with total page 410 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of Hydrogen on Flow and Fracture in a titanium Alloy written by Kumar V. Jatavallabhula and published by . This book was released on 1981 with total page 388 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 2004 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains the Proceedings of the 13th World Conference on Titanium.
