Download or read book The Effect of Phosphate Coatings on Fatigue Crack Initiation in Quenched and Tempered Low Alloy Steel written by R. Farrara and published by . This book was released on 1990 with total page 22 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 1991 with total page 1460 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 The Effect of Manganese Phosphate Coatings on Fatigue Crack Initiation written by Richard Farrara and published by . This book was released on 1990 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effect of a manganese phosphate coating on the fatigue crack initiation life of ASTM A723 high strength steel was determined. The phosphate coating process creates pitting (stress concentrators) on the surface that cause a dramatic reduction in crack initiation life. This deleterious effect on fatigue life increases as the applied stress level decreases. Keywords: Crack Initiation, Fatigue, High strength steel, Manganese phosphate, Shot peening.
Download or read book Government Reports Annual Index written by and published by . This book was released on 1991 with total page 1646 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sections 1-2. Keyword Index.--Section 3. Personal author index.--Section 4. Corporate author index.-- Section 5. Contract/grant number index, NTIS order/report number index 1-E.--Section 6. NTIS order/report number index F-Z.
Download or read book Australian national bibliography written by and published by National Library Australia. This book was released on 1961 with total page 1818 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Announcements Index written by and published by . This book was released on 1991 with total page 618 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book ASM Handbook written by ASM International. Handbook Committee and published by ASM International(OH). This book was released on 2000 with total page 1242 pages. Available in PDF, EPUB and Kindle. Book excerpt: This index eliminates that need to search through multiple back-of-the-book indexes to find where a subject is addressed. The A-to-Z listing will help users find important handbook content in volumes where they may not have thought to look.
Download or read book Annual Report 1989 90 written by New Brunswick. Department of Transportation and published by . This book was released on 1991 with total page 1272 pages. Available in PDF, EPUB and Kindle. Book excerpt: General activity review of associated branches and agencies to the Department which includes corporate securities registrations, a list of tenders received, and general financial data. Branches and agencies reviewed are responsible for motor vehicle activity, highway construction, traffic engineering, telecommunications and public utilities.
Download or read book Fatigue Crack Initiation in Carbon and Low alloy Steels in Light Water Reactor Environments written by and published by . This book was released on 1998 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: Section 111 of the ASME Boiler and Pressure Vessel Code specifies fatigue design curves for structural materials. The effects of reactor coolant environments are not explicitly addressed by the Code design curves. Recent test data illustrate potentially significant effects of light water reactor (LWR) coolant environments on the fatigue resistance of carbon and low-alloy steels. Under certain loading and environmental conditions, fatigue lives of test specimens may be shorter than those in air by a factor of H"0. The crack initiation and crack growth characteristics of carbon and low-alloy steels in LWR environments are presented. Decreases in fatigue life of these steels in high-dissolved-oxygen water are caused primarily by the effect of environment on growth of short cracks
Download or read book Metals Abstracts written by and published by . This book was released on 1990 with total page 1590 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effect of Aqueous Environments Upon the Initiation and Propagation of Fatigue Cracks in Low alloy Steels written by and published by . This book was released on 1996 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effect of elevated temperature aqueous environments upon the initiation and propagation of fatigue cracks in low-alloy steels is discussed in terms of the several parameters which influence such behavior. These parameters include water chemistry, impurities within the steels themselves, as well as factors such as the water flow rate, loading waveform and loading rates. Some of these parameters have similar effects upon both crack initiation and propagation, while others exhibit different effects in the two stages of cracking. In the case of environmentally-assisted crack (EAC) growth, the most important impurities within the steel are metallurgical sulfide inclusions which dissolve upon contact with the water. A ''critical'' concentration of sulfide ions at the crack tip can then induce environmentally-assisted cracking which proceeds at significantly increased crack growth rates over those observed in air. The occurrence, or non-occurrence, of EAC is governed by the mass-transport of sulfide ions to and from the crack-tip region, and the mass-transport is discussed in terms of diffusion, ion migration, and convection induced within the crack enclave. Examples are given of convective mass-transport within the crack enclave resulting from external free stream flow. The initiation of fatigue cracks in elevated temperature aqueous environments, as measured by the S-N fatigue lifetimes, is also strongly influenced by the parameters identified above. The influence of sulfide inclusions does not appear to be as strong on the crack initiation process as it is on crack propagation. The oxygen content of the environment appears to be the dominant factor, although loading frequency (strain rate) and temperature are also important factors.
Download or read book An Investigation of Elevated Temperature Fatigue Crack Initiation in 2 and 1 4 CR 1 MO Low Alloy Steel written by O. P. Keifer and published by . This book was released on 1984 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: Environmental effects in elevated temperature fatigue have been extensively studied and reported in the literature for 2 1/4 Cr-1 Mo steel. The results of cycles to failure (lumped initiation and propagation life) verses strain range have shown drastic reductions in fatigue life with a dwell period at compressive strains in each loading cycle. This thesis has separately examined the crack initiation and propagation stages for several specimens tested in air at 538 deg C without dwell and a single specimen with a five minute compressive dwell. With dwell, the crack initiation stage was severely reduced (by a factor greater than eleven) relative to testing without dwell. The results clearly indicate that oxide cracking is a precursor to crack initiation in the substrate. It is concluded that the fatigue life of this alloy must be estimated based on the crack propagation characteristics alone, since crack initiation can be expected very clearly (i.e., first few cycles) for any practical environment. Originator supplied keywords include: Fatigue, oxide cracking, 2 1/4 Cr - Mo Steel.
Download or read book Corrosion fatigue of high strength low alloy steels in aqueous chloride environments written by R. P. Gangloff and published by . This book was released on 1988 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Investigation of Elevated Temperature Fatigue Crack Initiation in 2 and 1 4 CR 1 MO Low Alloy Steel written by and published by . This book was released on 1984 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Environmental effects in elevated temperature fatigue have been extensively studied and reported in the literature for 2 1/4 Cr-1 Mo steel. The results of cycles to failure (lumped initiation and propagation life) verses strain range have shown drastic reductions in fatigue life with a dwell period at compressive strains in each loading cycle. This thesis has separately examined the crack initiation and propagation stages for several specimens tested in air at 538 deg C without dwell and a single specimen with a five minute compressive dwell. With dwell, the crack initiation stage was severely reduced (by a factor greater than eleven) relative to testing without dwell. The results clearly indicate that oxide cracking is a precursor to crack initiation in the substrate. It is concluded that the fatigue life of this alloy must be estimated based on the crack propagation characteristics alone, since crack initiation can be expected very clearly (i.e., first few cycles) for any practical environment. Originator supplied keywords include: Fatigue, oxide cracking, 2 1/4 Cr - Mo Steel.
Download or read book Corrosion Abstracts written by and published by . This book was released on 1981 with total page 596 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fatigue Fracture in a High strength Low alloy Steel written by K. R. L. Thompson and published by . This book was released on 1968 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effect of strength and stress level upon the mode and rate of fatigue crack growth in A1S14340 steel was studied by electron microfractography. It is shown that the mode of crack growth at high-strength levels is by a combination of transgranular striation formation and intergranular prior austenite grain boundary cracking, whereas in the lower-strength material only transgranular fracture occurs. The effect of stress level is found to alter slightly the proportion of the two fracture modes. At high-strength levels, measurement of striation spacing at various crack lengths indicates that the rate of crack growth is a function of the applied stress and crack length. Using this relationship it is shown that as the applied stress decreases, crack initiation becomes increasingly important in determining fatigue life. (Author).
Download or read book A Fracture Mechanics Approach for Estimating Fatigue Crack Initiation in Carbon and Low alloy Steels in LWR Coolant Environments written by and published by . This book was released on 2000 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: A fracture mechanics approach for elastic-plastic materials has been used to evaluate the effects of light water reactor (LWR) coolant environments on the fatigue lives of carbon and low-alloy steels. The fatigue life of such steel, defined as the number of cycles required to form an engineering-size crack, i.e., 3-mm deep, is considered to be composed of the growth of (a) microstructurally small cracks and (b) mechanically small cracks. The growth of the latter was characterized in terms of [Delta]J and crack growth rate (da/dN) data in air and LWR environments; in water, the growth rates from long crack tests had to be decreased to match the rates from fatigue S-N data. The growth of microstructurally small cracks was expressed by a modified Hobson relationship in air and by a slip dissolution/oxidation model in water. The crack length for transition from a microstructurally small crack to a mechanically small crack was based on studies on small crack growth. The estimated fatigue S-N curves show good agreement with the experimental data for these steels in air and water environments. At low strain amplitudes, the predicted lives in water can be significantly lower than the experimental values.
