Download or read book Micromechanisms of Crack Extension in Alloys written by John A. Blind and published by . This book was released on 1982 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work describes an investigation of the effect of manganese-bearing dispersoid particles on the fracture characteristics of peak aged Al-Mg-Si alloys. Current elastic and elastic-plastic fracture toughness parameters are reviewed. The applicability of these parameters as criteria for the onset of crack extension and their variation with alloy microstructure are examined based on experimental results for a series of alloys containing differing volume fractions of disperoid. High purity alloys were used to isolate the effect of dispersoids from that of coarse constituent particles. Also, for comparison, one alloy of commercial purity containing both disperoids and coarse iron-bearing inclusions was studied. The ductile fracture toughness, JIc, and the resistance to instability as measured by the tearing modulus, T, were found to increase with disperoid content. The values of these parameters were lower in the commercial purity alloy than for the equivalent high purity alloy. The effect of an increasingly triaxial state on fracture strain was measured using a series of notched tensile specimens. The alloy ductility was found to increase with disperoid content and to decrease with increased stress triaxiality. Crack tip plastic zone sizes on the midplane of compact tension specimens were measured using the SEM electron channelling pattern technique. Zone size was found to correlate with the square of the applied stress intensity factor. The constant of proportionality decreased with increasing disperoid content. The calculated work per unit area of new crack surface was found to correspond to the ductile fracture toughness measured for each alloy.
Download or read book Micromechanisms of Crack Extension in Aluminium Alloys written by Agah Uḡuz and published by . This book was released on 1990 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Micromechanism of Cleavage Fracture of Metals written by Jianhong Chen and published by Butterworth-Heinemann. This book was released on 2014-09-15 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this book the authors focus on the description of the physical nature of cleavage fracture to offer scientists, engineers and students a comprehensive physical model which vividly describes the cleavage microcracking processes operating on the local (microscopic) scale ahead of a defect. The descriptions of the critical event and the criteria for cleavage fracture will instruct readers in how to control the cleavage processes and optimize microstructure to improve fracture toughness of metallic materials. - Physical (mechanical) processes of cleavage fracture operating on the local (microscopic) scale, with the focus on the crack nucleation and crack propagation across the particle/grain and grain/grain boundaries - Critical event, i.e., the stage of greatest difficulty in forming the microcrack, which controls the cleavage fracture - Criteria triggering the cleavage microcracking with incorporation of the actions of macroscopic loading environment into the physical model - Effects of microstructure on the cleavage fracture, including the effects of grain size, second phase particles and boundary - Comprehensive description of the brittle fracture emerging in TiAl alloys and TiNi memory alloys
Download or read book Advances in Research on the Strength and Fracture of Materials written by D.M.R. Taplin and published by Elsevier. This book was released on 2013-10-22 with total page 873 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Research on the Strength and Fracture of Materials: Volume 1s—An Overview contains the proceedings of the Fourth International Conference on Fracture held at the University of Waterloo, Canada, in June 1977. The papers review the state of the art with respect to fracture in a wide range of materials such as metals and alloys, polymers, ceramics, and composites. This volume is comprised of 40 chapters and opens with a discussion on progress in the development of elementary fracture mechanism maps and their application to metal deformation processes, along with micro-mechanisms of fracture and the fracture toughness of engineering alloys. The next section is devoted to the fracture of large-scale structures such as steel structures, aircraft, cargo containment systems, nuclear reactors, and pressure vessels. Fracture at high temperatures and in sensitive environments is then explored, paying particular attention to creep failure by cavitation under non-steady conditions; the effects of hydrogen and impurities on brittle fracture in steel; and mechanism of embrittlement and brittle fracture in liquid metal environments. The remaining chapters consider the fracture of non-metallic materials as well as developments and concepts in the application of fracture mechanics. This book will be of interest to metallurgists, materials scientists, and structural and mechanical engineers.
Download or read book Micromechanisms of crack extension written by Conference on Micromechanisms of Crack Extension (1980, Cambridge) and published by . This book was released on 1980 with total page 315 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Micromechanisms of Fracture and Fatigue Crack Growth in Bulk Metallic Glass Alloys written by and published by . This book was released on 1998 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The recent development of metallic alloy systems which can be processed with an amorphous structure over large dimensions, specifically to form metallic glasses at low cooling rates (tilde 10 K/s), has permitted novel measurements of important mechanical properties. These include, fatigue crack growth and fracture toughness behavior, representing the conditions governing the subcritical and critical propagation of cracks. In the present study, bulk plates of a Zr41.2 Ti13.8 Cu12.5 Ni10 Be22.5 alloy, machined into 7 mm thick, 33 mm wide compact tension specimens and fatigue precracked following standard procedures, revealed fracture toughness in the fully amorphous structure of KIc tilde 55 MPa(square root m), i.e., comparable with that of a high strength steel or aluminum alloy. However, annealing to induce partial and full crystallization was found to result in a drastic reduction in fracture toughness to 1 MPa(square root m), i.e., comparable with silica glass. Under cyclic loading, whereas crack propagation behavior of the bulk amorphous metal was similar to that observed in traditional steel and aluminum alloys, the stress-life (S-N) properties of were markedly different. As in more traditional crystalline metallic alloys, the crack propagation mechanism in the metallic glass was associated with alternating blunting and resharpening of the crack tip as evidenced by striations on fatigue fracture surfaces. Alternatively, during S-N tests flaws apparently initiated quite easily due to the lack of microstructural barriers which would normally provide local crack arrest points, thereby giving rise to poor S-N properties.
Download or read book Developments in Fracture Mechanics The mechanics and mechanisms of fracture in metals written by G. G. Chell and published by Elsevier Science & Technology. This book was released on 1981 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Micromechanics of Crack Extension in Aluminium Alloys written by Agah Uguz and published by . This book was released on 1990 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of Fracture Micromechanisms on Crack Growth Resistance Curves of Irradiated Zirconium 2 5 Weight Percent Niobium Alloy written by CK. Chow and published by . This book was released on 1988 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: J-integral resistance curves, determined from curved compact specimens of irradiated Zr-2.5Nb, show an unusual three-stage behavior. Immediately after initiation of stable crack extension, the crack growth resistance increases at a low rate, followed by a second stage in which the J-resistance (JR) curve rises relatively steeply. Finally, the J-resistance curve decreases its slope, eventually reaching an approximately constant (zero slope) value. To explain this behavior, a series of compact specimens were pulled to various stages of crack extension and carefully examined using metallographic techniques and scanning electron fractography. The authors conclude that the decrease in crack growth resistance due to irradiation is a consequence of shear localization behavior, and the three-stage JR curve is attributed to an abrupt transition from plane-strain conditions to the development of very flat shear lips. This peculiar shear-lip formation is shown to be a consequence of strain localization behavior.
Download or read book Micromechanisms of Crack Extension Mechanics and Physics of Fracture 2 written by and published by . This book was released on 1980 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Micromechanisms of Crack Extension written by Metals Society. Science of Metals and Alloys Committee and published by . This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Micromechanisms of Crack Extension written by and published by . This book was released on 1980 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Developments in Fracture Mechanics written by and published by . This book was released on 1981 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Recent Advances in Fracture written by Rao K. Mahidhara and published by Minerals, Metals, & Materials Society. This book was released on 1997 with total page 422 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work focuses on in-depth mechanics and materials aspects pertinent to the phenomena of ductile fracture in engineering materials. The 31 papers present recent advances that provide an increased level of understanding of many aspects of this type of fracture, including micromechanisms of fracture, sources of toughness, the effects of microstructure, hydrostatic pressure, temperature and strain rate.
Download or read book Fracture Mechanics written by Ted L. Anderson and published by CRC Press. This book was released on 2005-06-24 with total page 630 pages. Available in PDF, EPUB and Kindle. Book excerpt: With its combination of practicality, readability, and rigor that is characteristic of any truly authoritative reference and text, Fracture Mechanics: Fundamentals and Applications quickly established itself as the most comprehensive guide to fracture mechanics available. It has been adopted by more than 100 universities and embraced by thousands of professional engineers worldwide. Now in its third edition, the book continues to raise the bar in both scope and coverage. It encompasses theory and applications, linear and nonlinear fracture mechanics, solid mechanics, and materials science with a unified, balanced, and in-depth approach. Reflecting the many advances made in the decade since the previous edition came about, this indispensable Third Edition now includes: A new chapter on environmental cracking Expanded coverage of weight functions New material on toughness test methods New problems at the end of the book New material on the failure assessment diagram (FAD) method Expanded and updated coverage of crack closure and variable-amplitude fatigue Updated solutions manual In addition to these enhancements, Fracture Mechanics: Fundamentals and Applications, Third Edition also includes detailed mathematical derivations in appendices at the end of applicable chapters; recent developments in laboratory testing, application to structures, and computational methods; coverage of micromechanisms of fracture; and more than 400 illustrations. This reference continues to be a necessity on the desk of anyone involved with fracture mechanics.
Download or read book Stress corrosion Cracking in High Strength Steels and in Titanium and Aluminum Alloys written by Benjamin Floyd Brown and published by . This book was released on 1972 with total page 388 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Discovery written by United States Air Force Academy and published by . This book was released on 1984 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt:
