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Repair Welding of Fusion Reactor Components

Description: Recent experimental investigations indicate that the repair welding of irradiated materials containing greater than 1 to 2.5 appm helium leads to catastrophic cracking in the heat affected zone of the weld. The high temperatures and cooling tensile stresses which occur during the welding process lead to enhanced helium bubble growth in the heat affected zone region, resulting in catastrophic cracking upon cooling. An investigation is proposed which seeks to determine the effect of stress state … more
Date: May 20, 1992
Creator: Chin, Bryan A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Comprehensive neutron cross-section and secondary energy distribution uncertainty analysis for a fusion reactor

Description: On the example of General Atomic's well-documented Power Generating Fusion Reactor (PGFR) design, this report exercises a comprehensive neutron cross-section and secondary energy distribution (SED) uncertainty analysis. The LASL sensitivity and uncertainty analysis code SENSIT is used to calculate reaction cross-section sensitivity profiles and integral SED sensitivity coefficients. These are then folded with covariance matrices and integral SED uncertainties to obtain the resulting uncertainti… more
Date: May 1, 1980
Creator: Gerstl, S.A.W.; LaBauve, R.J. & Young, P.G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Frank loop unfaulting mechanism in fcc metals during neutron irradiation

Description: The unfaulting mechanism whereby sessile Frank dislocation loops evolve into a complex tangle of glissile dislocations during irradiation of face centered cubic metals is not well understood. It is presumed that such loops grow by absorption of point defects until interactions develop which provide sufficient impetus for nucleation of an unfaulting event. The loops then become glissile, interact and form a dislocation network. An alternate mechanism which has been observed to occur in an austen… more
Date: May 1980
Creator: Gelles, D. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Review of recent irradiation-creep results

Description: Materials deform faster under stress in the presence of irradiation by a process known as irradiation creep. This phenomenon is important to reactor design and has been the subject of a large number of experimental and theoretical investigations. The purpose of this work is to review the recent experimental results to obtain a summary of these results and to determine those research areas that require additional information. The investigations have been classified into four subgroups based on t… more
Date: May 1, 1982
Creator: Coghlan, W.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Postirradiation Examinations of Fuel Pins from the GCFR F-1 Series of Mixed-Oxide Fuel Pins at 5. 5 at. % Burnup

Description: Postirradiation examinations were performed on five fuel pins from the Gas-Cooled Fast-Breeder Reactor F-1 experiment irradiated in EBR-II to a peak burnup of approximately 5.5 at. %. These encapsulated fuel pins were irradiated at peak-power linear ratings from approximately 13 to 15 kW/ft and peak cladding inside diameter temperatures from approximately 625 to 760°C. The maximum diametral change that occurred during irradiation was 0.2% .delta.D/D₀. The maximum fuel-cladding chemical interact… more
Date: May 1978
Creator: Johnson, C. E. & Strain, R. V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Ion implantation of boron in germanium

Description: Ion implantation of /sup 11/B/sup +/ into room temperature Ge samples leads to a p-type layer prior to any post implant annealing steps. Variable temperature Hall measurements and deep level transient spectroscopy experiments indicate that room temperature implantation of /sup 11/B/sup +/ into Ge results in 100% of the boron ions being electrically active as shallow acceptor, over the entire dose range (5 x 10/sup 11//cm/sup 2/ to 1 x 10/sup 14//cm/sup 2/) and energy range (25 keV to 100 keV) i… more
Date: May 1, 1985
Creator: Jones, K. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Radiation shielding issues on the FMIT

Description: The Fusion Materials Irradiation Test Facility (FMIT) is being built to study neutron radiation effects in candidate fusion reactor materials. The FMIT will yield high fluence data in a fusion-like neutron radiation environment produced by the interaction of a 0.1A, 35 MeV deuteron beam with a flowing lithium target. The design of the facility as a whole is driven by a high availability requirement. The variety of radiation environments in the facility requires the use of diverse and extensive … more
Date: May 1, 1981
Creator: Burke, R.J.; Davis, A.A.; Huang, S. & Morford, R.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Evolution of defect cluster distributions during irradiation

Description: Defects produced by irradiation are often strongly spatially correlated. Energetic primary recoil atoms produce cascades with vacant lattice sites predominantly in the central regions, and interstitial atoms at the periphery. A fraction of the defects produced form clusters during cascade events. Because of their spatial distribution more mobile interstitial atoms than vacancies are released into the matrix following the cascade events. Populations of vacancy and interstitial clusters evolve to… more
Date: May 1, 1991
Creator: Wiedersich, H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Radiation-effects limits on copper in superconducting magnets

Description: The determination of the response of copper stabilizers to neutron irradiation in fusion-reactor superconducting magnets requires information in four areas: (1) neutron flux and spectrum determination, (2) resistivity changes at zero field, (3) resistivity changes at field, and (4) the cyclic irradiation and annealing. Applications of our current understanding of the limits of copper stabilizers in fusion-reactor designs are explored in two examples. Recommendations for future additions to the … more
Date: May 25, 1983
Creator: Guinan, M.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Analytic method for calculating the time--temperature history of metal foils under pulsed irradiation and a Gaussian beam profile

Description: Utilization of a pulsed radiation source such as the Clinton P. Anderson Meson Physics Facility (LAMPF) for materials science studies requires knowledge of the time--temperature history of a subject metal foil. An analytic solution was derived to a two-dimensional heat flow equation, incorporating the LAMPF time structure and the LAMPF Gaussian beam spot profile. This calculational method is useful in designing experimental systems for materials science studies and can be done on a Hewlett--Pac… more
Date: May 1, 1979
Creator: Kmetyk, L. N. & Sommer, W. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Failure experience in refractory alloy-clad fuel pins applicable to space nuclear power

Description: Numerous in-reactor tests were conducted in the 1960's and early 1970's to develop fuel elements for space nuclear reactors. Most of the tests emphasized refractory metal-clad UN, UC, and UO/sub 2/. Previous reviews were provided by Weaver and Scott and by Gluyas and Watson. More recently, these data were reviewed for supporting information concerning the technical feasibility issues as they relate to the current reactor designs. This paper will focus on the fuel pin failure experience to obtai… more
Date: May 1, 1984
Creator: Dutt, D.S. & Cox, C.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The influence of N-ion irradiation on superconducting TiN

Description: The influence of disorder on the properties of the B1 phase superconductive compound titanium nitride has been investigated. Following synthesis and characterization of thin films of TiN, the materials were disordered progressively and uniformly by irradiation with nitrogen ions. The superconducting transition temperature T/sub c/ decreased and the low temperature electrical resistivity rho increased as lattice damage was introduced. The dependence of both T/sub c/ and rho on N-ion fluence phi … more
Date: May 1, 1987
Creator: Thompson, J. R.; Ellis, J. T.; Christen, D. K.; Sekula, S. T.; Lewis, J. D. & Williams, J. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effect of environmental stress on Sylgard 170 silicone elastomer

Description: Dow Corning Sylgard 170 Silicone Elastomer has been investigated to characterize its response to accelerated thermal aging, radiation exposure, and its behavior under applied compressive forces. Sylgard 170 response to accelerated thermal aging suggests the material properties are not particularly age dependent. Radiation exposures, however, produce significant, monotonic changes in both elongation and hardness with increasing absorbed radiation dose. Elastomer response to an applied compressiv… more
Date: May 1, 1985
Creator: Buckalew, W.H. & Wyant, F.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Gamma-ray induced displacement in D20 reactors

Description: Gamma-ray damage to tank walls is typically more severe in D{sub 2}O than in H{sub 2}O moderated lattices because of the much higher ratios of slow-to-fast neutron flux. To estimate this effect it was first necessary to develop energy dependent gamma-ray displacement cross sections for iron. These, along with coupled neutron-gamma-ray transport computations, provided a measure of displacement damage from this source in SRS reactor tank walls. Gamma-ray displacements originating from high energy… more
Date: May 1, 1990
Creator: Baumann, N.P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effects of tensile and compressive stresses on irradiation-induced swelling in AISI 316. [LMFBR]

Description: The results of two recent experiments indicate that the current perception of stress-affected swelling needs revision. It appears that compressive stresses do not delay swelling as previously modeled but actually accelerate swelling at a rate comparable to that induced by tensile stresses.
Date: May 1, 1985
Creator: Lauritzen, T.; Bell, W. L.; Konze, G. M.; Rosa, J. M.; Vaidyanathan, S. & Garner, F. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Microstructural comparison of HT-9 irradiated in HFIR and EBR-II

Description: A series of specimens of HT-9 heat 91354 have been examined following irradiation in HFIR to 39 dpa at 300, 400, 500 and 600/sup 0/C and following irradiation in EBR-II to 29 dpa at 390 and 500/sup 0/C. HFIR irradiation was found to have promoted helium bubble formation at all temperatures and voids at 400/sup 0/C. Cavitation had not been observed at lower fluence, nor was it found in EBR-II irradiated specimens. The onset of void swelling in HFIR is attributed to helium generation. The observa… more
Date: May 1, 1985
Creator: Gelles, D. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Assessment of the performance potential of the martensitic alloy HT-9 for liquid-metal fast-breeder-reactor applications

Description: Martensitic stainless steels appear to provide attractive alternatives to austenitic stainless steels for liquid metal fast breeder reactors (LMFBR). The United States National Cladding/Duct (NCD) Materials Development Program has selected Sandvik alloy HT-9 (12CrMoW) as one of six prime candidate alloys for advanced in-core structural materials having very high peak burnup capabilities. The NCD program, since 1974, has been accumulating engineering data for HT-9. Properties include swelling, i… more
Date: May 1, 1983
Creator: Straalsund, J. L. & Gelles, D. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Develop of the climb induced glide concept to describee in-reactor creep of FCC materials

Description: The Climb Induced Glide model (CIG) for irradiation creep is developed using a plastic flow law which has been successfully applied in the correlation of Type 316 stainless steel rupture data. This model is used to predict the stress and temperature dependence of irradiation creep and the transition from irradiation to thermal creep. The predictions of this model are compared and found to be qualitatively consistent with experimental data and microstructural information. This model allows predi… more
Date: May 1, 1979
Creator: Chin, B. A.; Straalsund, J. L. & Gilbert, E. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Correlation of mechanical property changes in neutron irradiated pressure vessel steels on the basis of spectral effects

Description: Defect production functions derived from atomistic modeling were evaluated for use in correlating yield stress changes of A212B and A302B pressure vessel steels irradiated in a wide variety of neutron spectra at low temperatures (40--90{degree}C) and low doses (<0.1 dpa). The irradiations were performed in RTNS-II, OWR, ORR and the HFIR pressure vessel surveillance positions. The data from RTNS-II, OWR and ORR are correlated fairly well on the basis of dpa, but the data from HFIR show that only… more
Date: May 1, 1989
Creator: Heinisch, H.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Environmental test program for superconducting materials and devices: Preliminary results of testing program at Savannah River Site

Description: The properties of YBa{sub 2}Cu{sub 3}O{sub 7-x} superconducting tapes designed and fabricated into SAFIRE-type, encapsulated, grounding links by the Ceramic Engineering Department at Clemson University are under investigation. Testing at the Savannah River Site will include gamma irradiation, vibration, and long-term evaluation. The gamma irradiation portion of testing has been completed. The long-term testing began in January and will continue. The vibration test has yet to be started.
Date: May 30, 1991
Creator: Randolph, H. (Westinghouse Savannah River Co., Aiken, SC (United States)) & Verebelyi, D. (Westinghouse Savannah River Co., Aiken, SC (United States) Clemson Univ., SC (United States))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Comparative gamma radiation and temperature effects on SiO/sub 2/, MgO and Al/sub 2/O/sub 3/ insulated nuclear instrument cable

Description: The relative merits of SiO/sub 2/, MgO and Al/sub 2/O/sub 3/ as insulation for nuclear instrument cables are investigated. Insulation resistance, voltage breakdown phenomena, capacitance, dissipation factors, and spurious voltage and current signals have been investigated on nuclear instrument cables under the combined effects of gamma irradiation (10/sup 5/ R/h) and temperature (to 450/sup 0/C). The SiO/sub 2/, MgO and Al/sub 2/O/sub 3/ cables tested were all fabricated to procedures that cont… more
Date: May 1, 1981
Creator: Cannon, C. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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DT fusion neutron irradiation of BNL--LASL superconductor wires, LASL YAG, Al/sub 2/O/sub 3/ and Spinel, LASL-IIT MgO, YAG, Al/sub 2/O/sub 3/ and Spinel, and NRL GeO/sub 2/ crystals, December 28, 1977

Description: The DT fusion neutron irradiation of eleven BNL-LAST superconductor wires, six NRL GeO/sub 2/ crystals, two YAG, two Spinel and two Al/sub 2/O/sub 3/ crystals for LASL and four LASL high purity single crystals of MgO, YAG, Spinel and Al/sub 2/O/sub 3/ is described. The sample position, beam-on time, and neutron dose record are given. The maximum fluence on any sample was 1.51 x 10/sup 16/ neutrons/cm/sup 2/.
Date: May 3, 1978
Creator: MacLean, S.C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Behavior of Type 316 stainless steel under simulated fusion reactor irradiation

Description: Fusion reactor irradiation response in alloys containing nickel can be simulated in thermal-spectrum fission reactors, where displacement damage is produced by the high-energy neutrons and helium is produced by the capture of two thermal neutrons in the reactions: /sup 58/Ni + n ..--&gt;.. /sup 59/Ni + ..gamma..; /sup 59/Ni + n ..--&gt;.. /sup 56/Fe + ..cap alpha... Examination of type 316 stainless steel specimens irradiated in HFIR has shown that swelling due to cavity formation and degradati… more
Date: May 1, 1978
Creator: Wiffen, F. W.; Maziasz, P. J.; Bloom, E. E.; Stiegler, J. O. & Grossbeck, M. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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