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Alloying effects on mechanical and metallurgical properties of NiAl

Description: Alloying effects were investigated in near-stoichiometric NiAl for improving its mechanical and metallurgical properties. Ternary additions of 19 elements at levels up to 10 at. % were added to NiAl; among them, molybdenum is found to be most effective in improving the room-temperature ductility and high-temperature strength. Alloying with 1.0 {plus_minus} 0.6% molybdenum almost doubles the room-temperature tensile ductility of NiAl and triples its yield strength at 1000C. The creep properties … more
Date: June 1, 1993
Creator: Liu, C. T.; Horton, J. A.; Lee, E. H. & George, E. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Use of trinitrobenzene sulfonate to determine the pK/sub a/ values of two active-site lysines of ribulosebisphosphate carboxylase/oxygenase

Description: An investigation into the active site of ribulosebisphosphate carboxylase using trinitrobenzene sulfonate to determine the pKa of lysine residues. 43 refs., 7 figs., 1 tab.
Date: January 1, 1985
Creator: Hartman, F. C.; Milanez, S. & Lee, E. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A TEM study of amorphization in NiTi irradiated with Ni/sup 2 +/ ions at room temperature

Description: Irradiation of a crystalline solid solution can cause the decomposition of the matrix into enhanced, modified thermal, or irradiation-induced precipitate phases. Irradiation can also transform the matrix into a new crystalline phase. Alternatively, the heavily irradiated matrix can become amorphous. Alloys of NiTi are intermetallic compounds with shape-memory applications whose amorphization is of both technological and basic scientific interest. Purpose of this paper is to observe some details… more
Date: January 1, 1987
Creator: Maziasz, P. J.; Packan, N. H.; Pedraza, D. F. & Lee, E. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effects of rapidly pulsed ion bombardment on microstructure and phase stability in a Ti-modified stainless steel

Description: A low-swelling Ti-modified austenitic stainless steel has been bombarded with pulsed 4 MeV Ni/sup + +/ and in some cases simultaneously with 0.2 to 0.4 MeV He/sup +/ ion beams at 948/sup 0/K over a dose range from 1 to 70 dpa. The interruption periods studied were 60, 1, 10/sup -3/, or 10/sup -5/ s on time with equal off time. At 1 dpa, pulsed irradiation caused interstitial dislocation loops (and subsequent MC precipitates) to be more refined with decreasing pulse periods down to the realm of … more
Date: January 1, 1985
Creator: Lee, E. H.; Packan, N. H.; Lewis, M. B. & Mansur, L. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Multiple sectioning and perforation techniques for TEM sub-surface studies. [4 MeV Ni/sup +2/ ions]

Description: Techniques for preparing multiple electron transparent regions at several depth levels below the surface of a metal disk specimen are described. These techniques are relatively rapid and find application in many areas involving surface studies. Examples are shown of multiple thin areas produced at intervals of approximately 200 nm below the original surface of a stainless steel bombarded with 4 MeV Ni/sup +2/ ions for void swelling studies.
Date: January 1, 1978
Creator: Lee, E.H. & Rowcliffe, A.F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Influence of injected helium on the phase instability of ion-irradiated stainless steel

Description: The influence of helium injection on phase instability under ion irradiation was studied for two modified 316 stainless steel alloys. Helium is required to nucleate voids in both alloys, though both exhibit phase instability without helium. The injected helium promotes associated growth of voids with precipitates. At low simultaneous helium injection rates 0 to 4 appm He/1 dpa), little or no effect on the precipitation process occurs. As the injection rate increases to 20 appm He/dpa, an increa… more
Date: January 1, 1980
Creator: Kenik, E.A. & Lee, E.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Ion bombardment damage in a modified Fe-9Cr-1Mo steel

Description: A normalized-and-tempered Fe-9Cr-1Mo steel, with small Nb and V additions, was bombarded with 4-MeV iron ions to 100 dpa at 400, 450, 500, 550, and 600/sup 0/C. Major damage feature was dislocation tangles which coarsened with increasing bombardment temperature. Sparse cavities were heterogeneously distributed at 500 and 550/sup 0/C. Incorporation of helium and deuterium simultaneously in the bombardments at rates of 10 and 45 appM/dpa, respectively, introduced very high concentrations of small… more
Date: January 1, 1984
Creator: Farrell, K. & Lee, E.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Spatial variation in void volume during charged particle bombardment: the effects of injected interstitials

Description: Experimental observations of the void volume at several depths along the range of 4 MeV Ni ions in 316 stainless steel are reported. The specimens were first preconditioned by neutron irradiation at temperatures of 450 and 584/sup 0/C to fluences of approximately 8 x 10/sup 26/ n/m/sup -2/. The void volume after ion bombardment to 60 dpa at the peak damage depth is significantly lower at the peak damage depth than in the region between that and the free surface. The ratio of the step height to … more
Date: January 1, 1979
Creator: Lee, E.H.; Mansur, L.K. & Yoo, M.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Precipitation and cavity formation in austenitic stainless steels during irradiation

Description: Microstructural evolution in austenitic stainless steels subjected to displacement damage at high temperature is strongly influenced by the interactions between helium atoms and second phase particles. Cavity nucleation occurs by the trapping of helium at partially coherent particle-matrix interfaces. The recent precipitate point defect collector theory describes the more rapid growth of precipitate-attached cavities compared to matrix cavities where the precipitate-matrix interface collects po… more
Date: January 1, 1981
Creator: Lee, E.H.; Rowcliffe, A.F. & Mansur, L.K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effects of thermomechanical treatment on phase stability and swelling in alloy D9

Description: Improvement in the swelling of AISI 316 may be achieved through adjustments to levels of Ni, Cr, Mo, Ti, and Si. Effort is concerned with optimizing the composition range for greater phase stability and improving alloy homogeneity. Irradiation response to variations in thermomechanical treatment (TMT) was studied. Swelling peak is suppressed by TMT which produces a high dislocation density or by increasing the solution treatment temperature to 1200/sup 0/C. (FS)
Date: January 1, 1979
Creator: Lee, E.H. & Rowcliffe, A.F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Mechanisms affecting swelling in alloys with precipitates

Description: In alloys under irradiation many mechanisms exist that couple phase instability to cavity swelling. These are compounded with the more familiar mechanisms associated with point defect behavior and the evolution of microstructure. The mechanisms may be classified according to three modes of operation. Some affect cavity swelling directly by cavity-precipitate particle association, others operate indirectly by precipitate-induced changes in sinks other than cavities and finally there are mechanis… more
Date: January 1, 1980
Creator: Mansur, L.K.; Haynes, M.R. & Lee, E.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Radiation damage and phase instability in irradiated stainless steel

Description: A 316 stainless steel, LS1A, with greater than nominal levels of silicon and titanium has been developed which exhibits high resistance to swelling under ion irradiation. The origin of this swelling resistance and the roles of silicon and titanium have been investigated in the current study.
Date: January 1, 1983
Creator: Kenik, E.A. & Lee, E.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effect of phosphorus on the swelling and precipitation behavior of austenitic stainless steels during irradiation

Description: It has been observed that increasing the volume fraction of the needle-shaped iron phosphide phase in austenitic stainless steels tends to inhibit void swelling during neutron irradiation. An earlier analysis showed that this effect could not be accounted for in terms of enhanced point defect recombination at particle-matrix interfaces. The behavior of the iron phosphide phase has been further examined using dual ion beam irradiations. It was found that the particle-matrix interface serves as a… more
Date: January 1, 1983
Creator: Lee, E.H.; Mansur, L.K. & Rowcliffe, A.F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Structure and composition of phases occurring in austenitic stainless steels in thermal and irradiation environments

Description: Transmission electron diffraction techniques coupled with quantitative x-ray energy dispersive spectroscopy have been used to characterize the phases which develop in austenitic stainless steels during exposure to thermal and to irradiation environments. In AISI 316 and Ti-modified stainless steels some thirteen phases have been identified and characterized in terms of their crystal structure and chemical composition. Irradiation does not produce any completely new phases. However, as a result … more
Date: January 1, 1980
Creator: Lee, E. H.; Maziasz, P. J. & Rowcliffe, A. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Mechanism of swelling suppression in phosphorous-modified Fe-Ni-Cr alloys

Description: Five simple alloys were ion irradiated at 948/sup 0/K in an experiment designed to investigate the mechanism of swelling suppression associated with phosphorous additions. One of the alloys was the simple ternary Fe-15Ni-13Cr, another had 0.05% P added and the other three had further additions of the phosphide precipitate-forming elements Ti and/or Si. Ion irradiations were carried out with heavy ions only (Ni or Fe) or with heavy ions followed by dual heavy ions and helium. The ternary with an… more
Date: January 1, 1986
Creator: Lee, E.H. & Mansur, L.K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effects of pulsed dual-ion irradiation on phase transformations and microstructure in Ti-modified austenitic alloy

Description: The influence of pulsed 4 MeV Ni ion bombardment, with and without simultaneous helium injection, has been explored in a low swelling, Ti-modified austenitic stainless steel. Irradiations were carried out to 70 dpa at 950/sup 0/K; the pulsing frequencies were either 60 s on/off or 1 s on/off. Compared to continuous irradiation, pulsing caused a decrease in the interstitial loop diameter at 1 dpa, although at higher doses the overall dislocation density was not affected. Pulsing and helium both … more
Date: January 5, 1983
Creator: Lee, E. H.; Packan, N. H. & Mansur, L. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Rapidly solidified long-range-ordered alloys. [(Fe, Co, Ni)/sub 3/V]

Description: The influence of rapid solidification processing on the microstructure of long-range-ordered alloys in the (Fe, Co, Ni)/sub 3/ V system has been studied by transmission electron microscopy. The main microstructural feature of the as-quenched alloys was a fine cell structure (approx. 300 nm diameter) decorated with carbide particles. This structure was maintained aftr annealing treatments which develop the ordered crystal structure. Other features of the microstructures both before and after ann… more
Date: January 1, 1981
Creator: Lee, E. H.; Koch, C. C. & Liu, C. T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Control of helium effects in irradiated materials based on theory and experiment

Description: Helium produced in materials by (n,..cap alpha..) transmutation reactions during neutron irradiations or subjected in ion bombardment experiments causes substantial changes in the response to displacement damage. In particular, swelling, phase transformations and embrittlement are strongly affected. Present understanding of the mechanisms underlying these effects is reviewed. Key theoretical relationships describing helium effects on swelling and helium diffusion are described. Experimental dat… more
Date: January 1, 1986
Creator: Mansur, L. K.; Lee, E. H.; Maziasz, P. J. & Rowcliffe, A. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effects of pulsed and/or dual ion irradiation on microstructural evolution in a Ti and Si modified austenitic alloy

Description: The influence of pulsed 4 MeV Ni-ion bombardment, with and without simultaneous helium injection, at 958 K and damage levels from 1 to 50 dpa has been studied in a low swelling, Ti- and Si- modified austenitic stainless steel. Compared to continuous irradiation, pulsing caused an increase in the number density of interstitial loops formed during irradiation. Helium also increased the nucleation of interstitial loops. The main precipitates formed were a large number of small TiC particles unifor… more
Date: January 1, 1983
Creator: Hishinuma, A.; Packan, N. H.; Lee, E. H. & Mansur, L. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effects of Si and Ti on the phase stability and swelling behavior of AISI 316 stainless steel. [Neutron and heavy ion irradiations]

Description: Swelling behavior of neutron irradiated stainless steels is influenced by solute segregation and preciptation phenomena. The extent to which in-reactor swelling behavior may be simulated by heavy ion irradiation depends upon the extent to which in-reactor phase changes are reproduced; this question is addressed by comparing the precipitation behavior under neutron irradiation with behavior during 4 MeV Ni ion irradiation for AISI 316 stainless steel and a related stainless steel containing addi… more
Date: January 1, 1978
Creator: Lee, E.H.; Rowcliffe, A.F. & Kenik, E.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fusion-relevant basic radiation effects: theory and experiment

Description: A summary is given of results of the basic radiation effects program at Oak Ridge National Laboratory, which are relevant to fusion reactor materials applications. The basic radiation effects program at ORNL is a large effort with the dual objectives of understanding the atomic and microstructural defect mechanisms underlying radiation effects and of determining principles for the design of radiation resistant materials. A strength of this effort is the parallel and integrated experimental and … more
Date: January 1, 1983
Creator: Mansur, L. K.; Coghlan, W. A.; Farrell, K.; Horton, L. L.; Lee, E. H.; Lewis, M. B. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Swelling suppression in phosphorous-modified Fe-Cr-Ni alloys during neutron irradiation

Description: Phosphorous-containing austenitic alloys in the solution annealed condition were irradiated at 745--760/degree/K. The alloys were variations on Fe--13Cr--15Ni--0.05P with respective additions of 0.8 Si, 0.2 Ti, or 0.8 Si /plus/ 0.2 Ti; also included were low (0.01) and zero P compositions (all values in wt. %). The reference ternary and the two phosphorous-only variations contained little precipitation and numerous voids and swelled rapidly, while the three variants containing P with Si and/or … more
Date: January 1, 1988
Creator: Lee, E. H. & Packan, N. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Triple Ion-Beam Studies of Radiation Damage in 9Cr2WVTa Ferritic/Martensitic Steel for a High Power Spallation Neutron Source

Description: To simulate radiation damage under a future Spallation Neutron Source (SNS) environment, irradiation experiments were conducted on a candidate 9Cr-2WVTa ferritic/martensitic steel using the Triple Ion Facility (TIF) at ORNL. Irradiation was conducted in single, dual, and triple ion beam modes using 3.5 MeV Fe{sup 2}, 360 keV He{sup +}, and 180 keV H{sup +} at 80, 200, and 350 C. These irradiations produced various defects comprising black dots, dislocation loops, line dislocations, and gas bubb… more
Date: August 1, 2001
Creator: Lee, EH
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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