Download or read book Influence of Microstructure and Environment on the Fatigue Crack Growth Fracture Topography of Ti 6Al 2Sn 4Zr 2Mo 0 1Si written by AJ. McEvily and published by . This book was released on 1981 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: An examination of fatigue fracture surfaces as influenced by microstructure (? processed versus ? + ? processed) and environment (air versus vacuum at 298 and 811 K) for a high-temperature creep-resistant near-? titanium alloy, Ti-6Al-2Sn-4Zr-2Mo-0.1Si, has been undertaken utilizing scanning electron microscopy. Results show that fracture topography is very sensitive to microstructural and environmental causes. Beta processing leads to a more irregular fracture surface than ? + ? processing. At low growth rates (10-6 mm/cycle) in air, shear mode growth predominates, resulting in large transgranular facets, whereas at growth rates of 10-5 in./cycle, striated and dimpled fracture features were present. At elevated temperatures, where oxidation effects were quite pronounced, particularly at low growth rates, the fracture surface was smoother than at room temperature, but faceting persisted to higher growth rates. In vacuum, however, the degree of faceting and striation formation was markedly reduced. Finally, the observed fractographic features influenced by microstructure and environment are discussed in terms of the mechanism of crack growth.
Download or read book The Effect of Microstructure on Fatigue Crack Propagation in Ti 6Al 6V 2Sn Alloy written by Maurice F. Amateau and published by . This book was released on 1971 with total page 43 pages. Available in PDF, EPUB and Kindle. Book excerpt: The fatigue crack growth behavior of Ti-6Al-6V-2Sn was investigated for five different microstructures, using contoured double-cantilever beam specimens. The fatigue crack growth behavior was compared with the mechanical strength, toughness, and ductility properties for each microstructure. The fatigue fracture suffaces were examined with a scanning electron microscope. Annealed structures consisting of equiaxed primary alpha have the lowest crack growth resistance, while the acicular alpha microstructure resulting from beta annealing has a growth resistance four times greater in the intermediate growth regime. No simple model of crack growth rate using gross mechanical properties describes the relative magnitude nor the ralative order of crack resistance among the different microstructures. (Author).
Download or read book Fracture and the Role of Microstructure Fatigue written by K. L. Maurer and published by . This book was released on 1982 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Microstructure and the Fracture Mechanics of Fatigue Crack Propagation written by EA. Starke and published by . This book was released on 1989 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: Microstructure is the principal independent variable which can be used to control the fatigue crack growth rate (FCGR) once loading conditions and environment are established. Microstructure affects the FCGR through its influence on strain distribution (slip character), slip length, plastic zone size, and crack path. These factors, in turn, can influence both crack closure and the materials sensitivity to aggressive environments. This paper reviews the authors' perception of the current understanding of the effect of microstructure on FCGRs.
Download or read book Some Effects of Microstructure and Environment on Fatigue Crack Propagation written by RB. Scarlin and published by . This book was released on 1979 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fatigue crack growth rates have been determined in nickel-base alloys both after a normal heat treatment and after heating for a further 10 000 h. The latter treatment causes coarsening of the ?`-particles so that they are no longer sheared by dislocations when the material is deformed. Differences in cracking rates at both ambient and elevated temperatures may be understood in terms of slip reversibility and oxide penetration when deformation occurs by shearing of precipitates.
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 Stephen W. Smith and published by . This book was released on 2001 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Influence of Microstructure and Moist Environment on Fatigue Crack Propagation in Metallic Alloys written by J. Petit and published by . This book was released on 1999 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fatigue Crack Growth in Ti 6Al 4V from Threshold to Unstable Fracture written by Maurice F. Amateau and published by . This book was released on 1973 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt: The fatigue crack growth of Ti-6Al-4V in the diffusion bond annealed condition was examined in the range of growth rates from 10 to the minus 12th power to 10 to the minus 4th power m/cycle with the use of compact tension and part-through-crack specimens. The effects of cyclic frequency and maximum stress were investigated. Fractured surfaces were examined by scanning electron microscopy over the entire range of crack growth. The fatigue data were fit empirically to a number of crack propagation laws, none of which was able to predict the entire range of crack growth from threshold to unstable fracture. When the fatigue crack growth rates were compared with those of Ti-6Al-4V of other microstructures, it was found that the diffusion bond annealed was among the most fatigue crack resistant of any microstructure examined. (Author).
Download or read book Microstructure Fracture Toughness and Fatigue Crack Growth Rate in Titanium Alloys written by Alok K. Chakrabarti and published by . This book was released on 1987-01-01 with total page 273 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of Microstructure Strength and Oxygen Content on Fatigue Crack Growth Rate of Ti 4 5Al 5 0Mo 1 5Cr CORONA 5 written by G. R. Yoder and published by . This book was released on 1983 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fatigue crack growth rate behavior in CORONA 5, an alloy developed for applications requiring high fracture toughness, has been examined for eight material conditions. These conditions were designed to give differences in microstructure, strength level, and oxygen content, in such a manner that the separate effects of these variables could be defined. For all eight conditions, fatigue crack growth rates (da/dN) are virtually indistinquishable over the full all spectrum of stress-intensity range (Delta K) examined. Concomitantly, it is noted that over the sizeable solution annealing range studied, the primary alpha-phase morphology was substantially invariant. A change in microfractographic appearance occurs at delta KT, as extensive secondary cracking along Alpha/Beta interfaces is observed at all hypertransitional levels of Delta K, but not for Delta K
Download or read book Effects of Microstructure and Frequency on Corrosion Fatigue Crack Growth in Ti 8Al 1Mo 1V and Ti 6Al 4V written by LA. Cooley and published by . This book was released on 1983 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fatigue crack growth studies were conducted on Ti-8Al-1Mo-1V and Ti-6Al-4V alloys in 3.5% NaCl aqueous solution. Each alloy was studied in two microstructural conditions and at two cyclic frequencies. Ti-8Al-1Mo-1V was heat-treated to produce a fine-grained duplex anneal microstructure and a coarse-grained Widmanstätten microstructure resulting from a beta anneal. The two microstructural conditions for the Ti-6Al-4V were an as-received mill anneal and a beta anneal. The two cyclic frequencies were 0.1 and 5.0 Hz. Each of the four alloy/microstructure combinations studied has been the subject of prior investigation regarding fatigue crack growth rate/microstructure interactions in ambient air environments. For both alloys, crack growth rates in air were found to be significantly reduced as a result of microstructural modifications associated with the beta anneal heat treatment. Although the salt water environment significantly accelerated crack growth rates for both alloys, this same ranking of fatigue crack growth resistance persisted in the present study. Both microstructures of the Ti-6Al-4V alloy exhibited a frequency crossover effect; in contrast, no significant frequency effects were observed in Ti-8Al-1Mo-1V in either microstructure. Similar frequency effects were seen in separate specimens cycled at a single constant frequency or in single specimens cycled at two alternating frequencies. Out-of-plane cracking was observed in both alloys in the beta-annealed condition. The effects of varying degrees of out-of-plane cracking on apparent crack growth rates are noted.
Download or read book Effects of Microstructure and Environment on Fatigue Crack Propagation in AISI 4340 Steel written by Dennis W. Stephens and published by . This book was released on 1976 with total page 510 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Microstructure and Frequency on Corrosion Fatigue Crack Growth in Ti 8Al 1Mo 1V and Ti 6Al 4V written by G. R. Yoder and published by . This book was released on 1981 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fatigue crack growth studies were conducted on Ti-8Al-1Mo-1V and Ti-6Al-4V alloys in 3.5% NaCl aqueous solution. Each alloy was studied in two microstructural conditions and at two cyclic frequencies. The Ti-8Al-1Mo-1V was heat treated to produce a fine-grained duplex anneal microstructure and a coarse-grained Widmanstatten microstructure resulting from a beta anneal. The two microstructural conditions for the Ti-6Al-4V were an as-received mill anneal and a beta anneal. The two cyclic frequencies were 01. and 5.0 Hz. Each of the four alloy/microstructure combinations studied has been the subject of prior investigation regarding fatigue crack growth rate/microstructure interactions in ambient air environments. For both alloys, crack growth rates in air were found to be significantly reduced as a result of microstructural modifications associated with the beta anneal heat treatment. Although the salt water environment significantly accelerated crack growth rates for both alloys, this same ranking of fatigue crack growth resistance persisted in the present study. Both microstructures of the Ti-6Al-4V alloy exhibited a frequency crossover effect; in contrast, no significant frequency effects were observed in the Ti-8Al-1Mo-1V, in either microstructure. Similar frequency effects were seen in separate specimens cycled at a single constant frequency or in single specimens cycled at two alternating frequencies. Out-of-plane cracking was observed in both alloys in the beta annealed condition. The effects of varying degrees of out-of-plane cracking on apparent crack growth rates are noted. (Author).
Download or read book Modeling Environmental Effects on Crack Growth Processes written by Metallurgical Society of AIME. Corrosion and Environmental Effects Committee and published by Society for Mining Metallurgy & Exploration. This book was released on 1986 with total page 410 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effects of Microstructure on Fatigue Crack Growth written by N. Knee and published by Parthenon Publishing Group. This book was released on 1986-01-01 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fracture Toughness and Crack Growth of Zerodur written by Michael J. Viens and published by . This book was released on 1990 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Environment Enhanced Fatigue Crack Propagation in Metals Inputs to Fracture Mechanics Life Prediction Models written by Richard P. Gangloff and published by . This book was released on 1993 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt:
