Author: D.N. BRASKIPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
VANADIUM ALLOYS WITH IMPROVED RESISTANCE TO HELIUM EMBRITTLEMENT.
Author: D.N. BRASKIVanadium Alloys with Improved Resistance to Helium Embrittlement
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 34
Book Description
A series of experimental vanadium alloys have been designed with small MC-type carbides in their microstructures to trap helium produced during neutron irradiation, thereby reducing helium embrittlement. The tensile properties and fabricability of the alloys were strongly influenced by the amounts of MC-forming-elements, especially carbon. Alloys with 0.05 and 0.10 wt % carbon exhibited slightly lower yield strengths at 420 to 600°C than vanadium alloys such as V-5Cr-5Ti, Vanstar-7, V-3Ti-1Si, and V-15Cr-5Ti. However, this characteristic may actually be an asset from the standpoint of resistance to irradiation hardening. After implantation with 300 appm 3He, both the V-Ti-C and V-Ti-Zr-C alloys exhibited less ductility losses at 600°C than the other vanadium alloys tested under comparable conditions. Examination of the experimental alloy microstructures by AEM showed that the small MC-type carbides did, in fact, trap helium and that they were responsible for the increased resistance to helium embrittlement of these alloys. 16 refs., 12 figs., 2 tabs.
Vanadium Alloys with Improved Resistance to Helium Embrittlement
Author: DN. BraskiPublisher:
ISBN:
Category : Helium embrittlement
Languages : en
Pages : 18
Book Description
A series of experimental vanadium alloys have been designed with small MC-type carbides in their microstructures to trap helium produced during neutron irradiation, thereby reducing helium embrittlement. The tensile properties and fabricability of the alloys were strongly influenced by the amounts of metal carbide (MC)-forming elements, especially carbon. Alloys with 0.05 and 0.10 wt% carbon exhibited slightly lower yield strengths at 420 to 600°C than vanadium alloys such as V-5Cr-5Ti, Vanstar-7, V-3Ti-lSi, and V-15Cr-5Ti. However, this characteristic may actually be an asset from the standpoint of resistance to irradiation hardening. After implantation with 300 atomic parts per million (appm) 3He, both the V-Ti-C and V-Ti-Zr-C alloys exhibited less ductility losses at 600°C than the other vanadium alloys tested under comparable conditions. Examination of the experimental alloy microstructures by analytical electron microscopy (AEM) showed that the small MC-type carbides did, in fact, trap helium and that they were responsible for the increased resistance to helium embrittlement of these alloys.
Effects of Radiation on Materials
Author: Roger E. StollerPublisher: ASTM International
ISBN: 080311477X
Category : Materials
Languages : en
Pages : 1315
Book Description
Symposium held in Nashville, Tennessee, June 1990. Almost two-thirds of these 91 papers are authored by researchers outside of the US (including information on research in the former USSR, Japan, and Europe). Topics include: current commercial power reactor systems; microstructural characterization
Scientific and Technical Aerospace Reports
Author: Effect of Neutron Irradiation on Vanadium Alloys
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Neutron-irradiated vanadium alloys were evaluated for their susceptibility to irradiation hardening, helium embrittlement, swelling, and residual radioactivity, and the results were compared with those for the austenitic and ferritic stainless steels. The VANSTAR-7 and V-15Cr-5Ti alloys showed the greatest hardening between 400 and 600°C while V-3Ti-1Si and V-20Ti had lower values that were comparable to those of ferritic steels. The V-15Cr-5Ti and VANSTAR-7 alloys were susceptible to helium embrittlement caused by the combination of weakened grain boundaries and irradiation-hardened grain matrices. Specimen fractures were entirely intergranular in the most severe instances of embrittlement. The V-3Ti-1Si and V-20Ti alloys were more resistant to helium embrittlement. Except for VANSTAR-7 irradiated to 40 dpa at 520°C, all of the vanadium alloys exhibited low swelling that was similar to the ferritic steels. Swelling was greater in specimens that were preimplanted with helium using the tritium trick. The vanadium alloys clearly exhibit lower residual radioactivity after irradiation than the ferrous alloys.
Mechanical Properties of Vanadium Alloys Doped with Helium Using Various Techniques
Author: K. AbePublisher:
ISBN:
Category : Fusion reactor materials
Languages : en
Pages : 13
Book Description
Helium embrittlement of binary vanadium alloys has been studied using three methods of helium doping. Helium doping using the tritium trick method yields severe embrittlement at 800°C for all the alloys studied including unalloyed vanadium. The boron-10 method resulted in slight ductility loss at 800°C. Specimens doped using cyclotron implantation showed virtually no ductility loss, but some effect of helium was observed in the fractured surface. Helium release measured during tension tests has good correlation with the degree of embrittlement. These results are discussed in terms of the different state of helium clusters/ bubbles as a result of different doping methods.
Energy Research Abstracts
Author: Selected Properties of Vanadium Alloys for Reactor Application
Author: K. F. SmithPublisher:
ISBN:
Category : Alloys
Languages : en
Pages : 40
Book Description
Results indicate the preliminary feasibility of these alloys from all viewpoints under examination and suggest the desirability of studying fabrication problems of alloys and improved reduction methods for vanadium metal.
Brittle-ductile Transition in Vanadium
Author: Benny A. LoomisPublisher:
ISBN:
Category : Alloys
Languages : en
Pages : 106
Book Description