Download or read book Effect of Nickel on Irradiation Hardening and Microstructure Evolution of Proton Irradiated Fe Cu Alloys written by S. Yamaguchi and published by . This book was released on 2001 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hardness measurements and microstructure examinations of Fe(-C)-Cu-Ni model alloys were performed following 1 MeV proton irradiation below 80°C. Microstructural examinations by transmission electron microscope (TEM) were carried out by means of a cross section method. A band of damage structures, parallel to the irradiated surface, was observed at a depth of 6.5 ? m in agreement with calculation based on the TRIM code. TEM observation revealed that the band consisted of high density of small black spots, which were considered to be interstitial-type dislocation loops. The amount of irradiation hardening increased with increase in copper concentration. An addition of 0.6wt%Ni to Fe-Cu alloys further increased the hardening, although the effect was reduced with increasing copper concentration. Irradiation hardening of pure iron was also significantly increased by the addition of nickel. The size and number density of the spot-like structures in Fe-Cu alloys decreased and increased, respectively, with addition of nickel. Three recovery stages were found in Fe-Cu-Ni alloys during post-irradiation isochronal annealing to 675°C: the stages are at around 150°C, 400°C and 600°C. The first stage was only observed in nickel-containing alloys, while the third stage was only observed in copper-containing alloys. After annealing to 375°C, the density of spot-like structures decreased in Fe-Cu-Ni alloy but increased in Fe-Cu alloy, while for both the size of spots increased.
Download or read book Microstructure Evolution in Proton irradiated Austenitic Fe Cr Ni Alloys Under LWR Core Conditions written by Jian Gan and published by . This book was released on 1999 with total page 710 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Radiation on Materials written by Stan T. Rosinski and published by ASTM International. This book was released on 2001 with total page 879 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Copper Concentration and Neutron Flux on Irradiation Hardening and Microstructure Evolution in Fe Cu Model Alloys written by K. Morishita and published by . This book was released on 2001 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: Irradiation hardening and microstructure evolution under neutron irradiation have been investigated for pure Fe, Fe-0.15Cu, Fe-0.28Cu and Fe-0.46Cu alloys. All the alloys were annealed at 780°C for 20 min and quenched in iced water. Neutron irradiations were performed in the Japan Material Test Reactor (JMTR) up to a fluence of about 1 x 1022n/m2 at different fluxes (3.0 x 1016 and 1.5 x 1015 n/m2s) at 290°C utilizing a so-called "multi-division temperature control irradiation rig" to investigate flux effects under controlled irradiation temperature and flux. The irradiation hardening increased with increasing copper concentration. Positron annihilation lifetime spectrometry (PAS) revealed that the second lifetime component (?2) was observed only in pure iron and Fe-0.15Cu alloy irradiated at the low flux condition. As for the flux effect, the irradiation hardening was larger at the lower flux condition in all the model alloys and A533B steel. Post-irradiation annealing experiments indicated that there were two recovery stages: the first was above 350°C and the second was around 550°C. The amount of hardening recovery in the first stage decreased with increasing copper concentration and depended on the flux; a larger recovery was observed at the lower flux condition. In contrast, the amount of recovery in the second stage increased with increasing copper concentration and was independent of the flux. It is considered that the first recovery is related to the annealing out-of-matrix defects and the second one is due to dissolution of copper precipitates. The ?2 of PAS disappeared after the annealing at 350°C, indicating that microvoids decomposed during the annealing.
Download or read book The Influence of Nickel Content on Microstructures of Fe Cr Ni Austenitic Alloys Irradiated with Nickel Ions written by and published by . This book was released on 1990 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objectives of this effort is to identify the mechanisms involved in the radiation-induced evolution of microstructure in materials intended for fusion applications. The results of this study are useful in interpreting the results of several other ongoing experiments involving either spectral or isotopic tailoring to study the effects of helium on microstructure evolution. Ion-irradiated Fe-15Cr-XNi (X = 20, 35, 45, 60, 75) ternary alloys and a 15Cr-85Ni binary alloy were examined after bombardment at 675°C and compared to earlier observations made on these same alloys after irradiation in EBR-II at 510 or 538°C. The response of the ion-irradiated microstructures to nickel content appears to be very consistent with that of neutron irradiation even though there are four orders of magnitude difference in displacement rate and over 200°C difference in temperature. It appears that the transition to higher rates of swelling during both types of irradiation is related to the operation of some mechanisms that is not directly associated with void nucleation. 6 refs., 8 figs.
Download or read book Radiation induced Changes in Microstructure written by F. A. Garner and published by ASTM International. This book was released on 1987 with total page 919 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Damage Structures of Proton Irradiated Fe 0 3wt Cu Alloy written by M. Hasegawa and published by . This book was released on 1996 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: Microstructural observation was performed on an Fe-0.3wt.%Cu alloy using a cross-sectional method. The specimens were solution treated and aged at 893K for 22.5h, followed by proton irradiation up to a fluence of 3x1021H+/m2(0.2 dpa at a peak position) at 353K. A band of structure, 0.8?m wide, was observed in a region 6.5 ?m beneath the irradiated surface. The band consisted of a high density of black spot damage, which average size and number density at the center of the band was determined to be 2.3nm and 2.2x1026/m3, respectively. Besides the black spot damage, a number of small structures (3nm) were observed in the defect band at strong two beam condition, while precipitates having F.C.C structure with a lattice constant of 10.16A and large precipitates (6nm) causing halo rings corresponding to F.C.C. copper were observed at the region in and around both sides of the band. Taking in account results of micro vickers hardness and positron life-time measurements in Fe-Cu alloys, radiation hardening observed in Fe-0.3wt.%Cu alloy is attributed mainly to the radiation damage structures, such as dislocation loops and microvoids. However, It is pointed out that interaction between copper and carbon plays an important role on the microstructural evolution under irradiation and the resultant hardening in Fe-C-Cu alloys.
Download or read book Microstructural Characterization of Irradiated Fe Cu Ni P Model Steels written by and published by . This book was released on 1987 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: The microstructure of Fe-Cu-Ni-P model pressure vessel steels after neutron irradiation and thermal aging has been characterized by atom probe field-ion microscopy and augmented by transmission electron microscopy. High densities of small, roughly spherical or disc shaped copper clusters/precipitates were observed in the neutron irradiated alloys that contained copper. Small spherical phosphorus clusters were observed in the irradiated copper-free alloys, and copper phosphides were observed in a high phosphorus Fe-Cu-Ni-P alloy. None of these clusters/precipitates were observed in the thermally aged materials. The increases in the tensile and yield strengths that were observed after neutron irradiation resulted from these clusters and other lattice defects.
Download or read book Energy Research Abstracts written by and published by . This book was released on 1993 with total page 762 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiannual, with semiannual and annual indexes. References to all scientific and technical literature coming from DOE, its laboratories, energy centers, and contractors. Includes all works deriving from DOE, other related government-sponsored information, and foreign nonnuclear information. Arranged under 39 categories, e.g., Biomedical sciences, basic studies; Biomedical sciences, applied studies; Health and safety; and Fusion energy. Entry gives bibliographical information and abstract. Corporate, author, subject, report number indexes.
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1974 with total page 852 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fusion Energy Update written by and published by . This book was released on 1979 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Hardness and Microstructure Changes with Thermal Annealing of Neutron Irradiated Fe Cu Alloys written by S. Suzuki and published by . This book was released on 2001 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: In order to investigate mechanisms in recovery of irradiation-induced hardness by thermal annealing for pressure vessel steels containing copper, Fe-0.6 wt.% Cu model alloys irradiated to a dose of 0.0055 dpa at 290°C in JMTR were isochronally annealed at temperatures ranging from 250 to 600°C (?T = 50°C, ?t =15 min). Vickers hardness measurements showed that 70% of the irradiation-induced hardness was eliminated by the annealing. TEM examinations revealed that three kinds of precipitates were formed in the specimens; those are small copper precipitates (disk-shaped, 3-8 nm in diameter), ordered structures of possibly Cu3Fe (L12-type, a0 = ~0.343 nm) and Fe3O4 particles (structure of spinel-type). Copper precipitates slightly increased the number density and size with the post-irradiation annealing below 400 °C, indicating clearly that copper precipitates contributed to hardening, though the degree may be small. The ordered structure was proven by the occurrence of superlattice reflections in selected area diffraction patterns. The post-irradiation annealing reduced the intensities of the superlattice reflections and the zone of Cu3Fe-structure. The ordered structure of Cu3Fe was observed to be destroyed by thermal annealing, resulting in a remarkable decrease in hardness. The hardness during thermal annealing was concluded to be governed by two competitive processes of hardening by the growth of copper precipitates and softening by the order-disorder transformation of Cu3Fe.
Download or read book The Effects of Nickel on Microstructural Development and Microchemical Changes in Neutron Irradiated Fe Cr Mn Based Steels written by H. Takahashi and published by . This book was released on 1992 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: Microstructural changes and solute segregation in austenitic Fe-Cr-Mn-Ni alloys have been studied after neutron irradiation to 25 dpa (maximum) in FFTF/MOTA. Voids were nucleated in all of the specimens in the temperature range of 420 to 650°C, and a swelling peak was observed to form at 550°C. The void suppression effect of nickel additions did not occur in these alloys. Precipitates were formed in the matrix and/or on grain boundaries and were mostly identified as M23C6. The composition in the grain boundary area changed, and the chromium (Cr) concentration near the precipitates became higher. On the other hand, manganese and chromium were depleted, and nickel was enriched in the grain boundary area, but without precipitation. Other phases such as ferrite and sigma could not be recognized. Thus, it was revealed that the addition of nickel to Fe-Cr-Mn alloy stabilizes the austenite even in the grain boundary area where segregation is marked.
Download or read book Irradiation Hardening and Microstructural Evolution in Fe Cu Model Alloys written by M. Narui and published by . This book was released on 2004 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: Irradiation hardening and microstructural evolution und neutron and electron irradiation have been investigated for pure-Fe and Fe-Cu model alloys. Neutron and electron irradiations were performed in the Japan Material Test Reactor (JMTR) and with using Phodtron electron accelerator at about 290°C and 270±30°C, respectively. Irradiation hardening of pure-Fe and Fe-Cu model alloys is saturated at about 1 x 10-3 dpa in both the neutron and electron irradiation. Irradiation hardening recovered in two temperature ranges. The recovery in the lower temperature range depends on copper concentration and electron irradiation dose, while the recovery at a higher temperature range does not. Recovery behavior of the irradiation hardening suggests indirectly that copper atoms suppress the growth of interstitial clusters. The recovery behavior of positron lifetime does not coincide with that of the hardness, suggesting that the vacancy clusters are not the direct main factor controlling the hardening by matrix damages.
Download or read book ERDA Energy Research Abstracts written by and published by . This book was released on 1989 with total page 848 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Hardening Characteristics of Ion Irradiated Iron Based Model Alloys written by Y. Arai and published by . This book was released on 1993 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fe-C-Cu, Fe-C-Ni, and Fe-C-Cu-Ni model alloys were prepared in order to investigate the effects of copper and nickel on radiation embrittlement. They were irradiated with 4 MeV Ni3+ ions at 563 K to introduce displacement damage, followed by a micro-Vickers hardness test employing low load (0.5 g). It was observed that greater hardening occurred for samples of larger copper content, and that hardening of the samples containing both copper and nickel was greater than hardening of the ones containing copper or nickel solely for samples irradiated to 10-2 and 10-1 dpa. Increased hardness after annealing occurred for Fe-0.1C-0.2Cu and Fe-0.lC-0.4Cu. Small defect clusters of approximately 3 nm in diameter were observed by transmission electron microscopy (TEM) of the irradiated Fe-0.1C and Fe-0.1C-0.4Cu samples, which cause hardening.
Download or read book Microstructure Evolution During Irradiation Volume 439 written by Ian M. Robertson and published by . This book was released on 1997-06-25 with total page 770 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book from MRS discusses the evolution of a material's microstructure as a result of its interaction with energetic particles such as ions, neutrons or electrons. The book is inter-disciplinary and emphasizes all classes of materials including metals, intermetallic compounds, ceramics, polymers, superconductors, semiconductors and insulators. A strong focus is placed on experimental techniques for measuring and quantifying damage and microstructure changes, and on computer simulation techniques for predicting and understanding this phenomena. Topics include: ion-implantation damage in semiconductors; radiation damage in metals; radiation damage in ceramics; radiation effects in polymers and beam-induced effects.
