Nuclear Engineering Commons^™

Effect Of Silicon Content On The Corrosion Resistance And Radiation-Induced Embrittlement Of Materials For Advanced Heavy Liquid Metal Nuclear Systems: Quarterly Progress Report (February – April 2005), Ajit K. Roy

Transmutation Sciences Materials (TRP)

This proposal is intended to study the effect of Si content not only on the corrosion resistance but also on the radiation-induced embrittlement of martensitic stainless steels. The susceptibility of these alloys with different Si content to stress corrosion cracking, general corrosion and localized corrosion will be evaluated in the molten LBE and aqueous environments of different pH values using state-of-the-art testing techniques. Testing in the aqueous media is intended to develop baseline data for comparison purpose. Radiation-induced embrittlement of these alloys will initially be studied by irradiating the test specimens with bremmstrahlung gamma radiation from 20-40 MeV electron beams …

Effect Of Silicon Content On The Corrosion Resistance And Radiation-Induced Embrittlement Of Materials For Advanced Heavy Liquid Metal Nuclear Systems: Quarterly Progress Report (November 2004 – January 2005), Ajit K. Roy

Transmutation Sciences Materials (TRP)

This proposal is intended to study the effect of Si content not only on the corrosion resistance but also on the radiation-induced embrittlement of martensitic stainless steels. The susceptibility of these alloys with different Si content to stress corrosion cracking, general corrosion and localized corrosion will be evaluated in the molten LBE and aqueous environments of different pH values using state-of-the-art testing techniques. Testing in the aqueous media is intended to develop baseline data for comparison purpose. Radiation-induced embrittlement of these alloys will initially be studied by irradiating the test specimens with bremmstrahlung gamma radiation from 20-40 MeV electron beams …

Fundamental And Applied Experimental Investigations Of Corrosion Of Steel By Lbe Under Controlled Conditions: Kinetics, Chemistry, Morphology, And Surface Preparation: Quarterly Report (January 2005-April 2005), Allen L. Johnson, John Farley, Dale L. Perry

Transmutation Sciences Materials (TRP)

This project has four components:

• The fabrication of a materials test apparatus with unique capabilities,
• Comparative studies of steel corrosion under gas phase conditions comparable to the Lead Bismuth Eutectic (LBE) oxygen control conditions,
• Isotope labeling studies, and
• Collaborative efforts with other workers in the field.

Summary of accomplishments:

• Started occupation of the High Temperature Materials Experimental Facility.
• Presented a paper at the meeting of the American Chemical Society in San Diego in March 13-17.
• Currently reviving the ion beam for implantation experiments.
• Currently analyzing 38 steel samples from the DELTA loop from LANL.

Developing A Sensing System For The Measurement Of Oxygen Concentration In Liquid Pb-Bi Eutectic: Quarterly Progress Report (Jan. 01 – March. 31, 2005), Yingtao Jiang, Bingmei Fu

Transmutation Sciences Materials (TRP)

We performed data analysis on the data collected from LANL test loop. One student was been hired to perform the data analysis. A new proposal is submitted to TRP program. We have one paper accepted for publication in International Journal of Heat and Mass Transfer, and another paper accepted for oral presentation by IEEE International Symposium of Circuits and Systems for the track Chemical Sensors. A manuscript regarding to the RGA analysis for the calibration of oxygen sensor is on the way.

Theoretical Modeling Of Protective Oxide Layer Growth In Non-Isothermal Lead-Alloys Coolant Systems: Quarterly Progress Report (01/01/05- 03/31/05), Yitung Chen

Transmutation Sciences Materials (TRP)

The goal of the proposed research project is to provide basic understanding of the protective oxide layer behaviors and to develop oxide layer growth models of steels in non-isothermal lead-alloys (lead or lead-bismuth eutectic) coolant systems. It is widely recognized that the corrosiveness of the lead-alloys is a critical obstacle and challenge for which it can be safely used or applied in the nuclear coolant systems. Active oxygen control technique can promote the formation of the “self-healing” oxide films on the structural material surface, drastically reducing steel corrosion and coolant contamination. Many experiments of steels exposed to flowing lead-alloys have …

Effect Of Silicon Content On The Corrosion Resistance And Radiation-Induced Embrittlement Of Materials For Advanced Heavy Liquid Metal Nuclear Systems: Quarterly Progress Report (August 2004 – October 2004), Ajit K. Roy

Transmutation Sciences Materials (TRP)

The purpose of this collaborative research project involving the University of Nevada Las Vegas (UNLV), Los Alamos National Laboratory (LANL) and Idaho State University (ISU) is to evaluate the effect of silicon (Si) content on the corrosion behavior and radiation-induced embrittlement of martensitic stainless steels having chemical compositions similar to that of the modified 9Cr-1Mo steel. Recent studies at LANL involving Alloy EP-823 of different Si content have demonstrated that increased Si content in this alloy may enhance the corrosion resistance in molten lead-bismutheutectic (LBE). Since very little data exists in the open literature on the beneficial effect of Si …

Corrosion Of Steel By Lead Bismuth Eutectic, John Farley, Allen L. Johnson, Dale L. Perry

Transmutation Sciences Materials (TRP)

There is an active international interest in lead-bismuth eutectic and similar liquid lead systems because of the relevance to the transmutation of nuclear waste, fast reactors, and spallation neutron sources.

Materials in these systems must be able to tolerate high neutron fluxes, high temperatures, and chemical corrosion. For lead bismuth eutectic (LBE) systems, there is an additional challenge because the corrosive behaviors of materials in LBE are not well understood. Most of the available information on LBE systems has come from the Russians, who have over 80 reactor-years experience with LBE coolant in their Alpha-class submarine reactors. The Russians found …

Environment-Induced Degradation And Crack-Growth Studies Of Candidate Target Materials, Ajit K. Roy

Transmutation Sciences Materials (TRP)

The primary objective of this task was to evaluate the effects of environmental and mechanical parameters on environment induced degradations of candidate target structural materials for applications in spallation-neutron-target systems. The materials selected for evaluation and characterization were martensitic stainless steels including Alloys HT-9, EP-823, and 422.

Accelerator-driven transmutation systems involve bombarding a target material such as molten lead-bismuth-eutectic (LBE) by a proton beam, thereby producing neutrons. The molten LBE target will be contained in a subsystem structural container made of a suitable material such as Alloys HT-9, EP-823, and 422. During the transmutation process, the target structural material may …

Modeling Corrosion In Oxygen Controlled Lbe Systems With Coupling Of Chemical Kinetics And Hydrodynamics, Samir Moujaes, Yitung Chen

Transmutation Sciences Materials (TRP)

The corrosion of structural materials is a major concern for the use of lead-bismuth eutectic (LBE) systems for nuclear applications such as in transmuter targets or fast reactors. Corrosion in liquid metal systems can occur through various processes, including, for example, dissolution, formation of inter-metallic compounds at the interface, and penetration of liquid metal along grain boundaries. Predicting the rate of these processes depends on numerous system operational factors: temperature, system geometry, thermal gradients, solid and liquid compositions, and velocity of the liquid metal, to name a few. Corrosion, along with mechanical and/or hydraulic factors, often contributes to component failure. …

Development Of A Mechanistic Understanding Of High-Temperature Deformation Of Alloy Ep-823, Ajit K. Roy, Brendan O'Toole

Transmutation Sciences Materials (TRP)

During the transmutation process, a significant amount of heat can be generated in a molten lead-bismuth-eutectic (LBE) target, which will be contained in a subsystem structural container made of a suitable martensitic iron-chromium-molbdenum (Fe-Cr-Mo) stainless steel such as Alloys EP-823, HT-9 and 422. These materials will be subjected to high tensile stresses while they are in contact with the molten LBE at temperatures ranging between 400 and 600^oC. Therefore, a research program was conducted to evaluate the deformation characteristics of all three alloys in properly heat-treated conditions at temperatures relevant to the operating conditions.

Developing A Sensing System For The Measurement Of Oxygen Concentration In Liquid Pb-Bi Eutectic, Yingtao Jiang, Bingmei Fu

Transmutation Sciences Materials (TRP)

Although liquid lead-bismuth eutectic (LBE) is a good candidate for the coolant that can be employed in a subcritical transmutation blanket, it is known to be very corrosive to stainless steel, the material used in the containment structure. To mitigate this problem, trace levels of oxygen can be introduced into the system, causing the formation of a protective oxide layer at the interface between the LBE and steel. The proper formation of this oxide layer largely depends on the accurate measurement and subsequent control of the oxygen concentration in liquid LBE.

Yttria Stabilized Zirconia (YSZ) oxygen sensors, using molten bismuth …

Fundamental And Applied Experimental Investigations Of Corrosion Of Steel By Lbe Under Controlled Conditions: Kinetics, Chemistry Morphology, And Surface Preparation, John Farley, Allen L. Johnson, Dale L. Perry

Transmutation Sciences Materials (TRP)

Advanced nuclear processes such the transmutation of nuclear waste, fast reactors, and spallation neutron sources require advanced materials systems to contain them. In particular, a successful program in nuclear waste processing that includes transmutation in accelerator-driven systems and fast reactors requires structural materials that are stable in the presence of non-moderating coolants. A prime candidate for such a coolant is Lead Bismuth Eutectic (LBE).

Materials in these systems must be able to tolerate high neutron fluxes, high temperatures, and chemical corrosion. For LBE systems, there is an additional challenge because the corrosive behaviors of materials in lead bismuth are not …

Effect Of Silicon Content On The Corrosion Resistance And Radiation- Induced Embrittlement Of Materials For Advanced Heavy Liquid Metal Nuclear Systems, Ajit K. Roy

Transmutation Sciences Materials (TRP)

This task is focused on the evaluation of the effect of Si content on the corrosion behavior and radiation-induced embrittlement of martensitic steels having chemical compositions similar to that of modified 9Cr-1Mo steel. Numerous state-of-the-art experimental techniques are currently being planned to be employed to achieve the desired research goal.

Theoretical Modeling Of Protective Oxide Layer Growth In Non-Isothermal Lead Alloy Coolant Systems, Yitung Chen, Jinsuo Zhang, Huajun Chen, Jichun Li

Transmutation Sciences Materials (TRP)

In advanced nuclear energy systems, lead-alloys (e.g., lead, lead bismuth eutectic) emerge as strong candidates for transmutation and advanced reactor systems as nuclear coolants and high-power spallation neutron targets. However, it is widely recognized that corrosion of materials caused by lead-alloys presents a critical barrier to their industrial use. A few experimental research and development projects have been set up by different groups such as LANL to study the corrosion phenomena in their test facilities and to develop mitigation techniques and materials.

The goal of the proposed research project is to provide basic understanding of the protective oxide layer behaviors …

Corrosion Barrier Development For Lbe Corrosion Resistance, Biswajit Das

Transmutation Sciences Materials (TRP)

In the last quarter, a specialized sample holder was developed for the anodization of alumina on steel. In addition, it was determined that oxalic acid was the most appropriate acid for the anodization of these structures. The steel samples obtained from LANL were first cut into a number of pieces, each measuring 11mm x 8mm x 1.6mm, to allow multiple experiments. Special care was taken to ensure that the cutting process did not damage the samples. After investigation of several techniques, including laser cutting, the samples were cut using EDM wires. The cut steel pieces did not show any damage …

Corrosion Barrier Development For Lbe Corrosion Resistance: Quaterly Report, Biswajit Das

Transmutation Sciences Materials (TRP)

With the demonstration of formation of nanoporous alumina on steel and its good adhesion to substrate under thermal cycling, the next project task was to synthesize Chromium nanowires inside the alumina pores. During the previous quarter, a specialized sample holder was developed towards this goal. Various techniques for the deposition of Chromium were investigated and electro-deposition was determined to be the most suitable approach due to the large aspect ratio of the pores. A challenge in using electro-deposition for porous alumina is the potential sealing of the pores in aqueous solutions at higher temperatures. To avoid this problem, a search …

Development Of Nanostructure Based Corrosion-Barrier Coatings On Steel For Transmutation Applications, Biswajit Das

Transmutation Sciences Materials (TRP)

Advanced transmutation systems require structural materials that are able to withstand high neutron fluxes, high thermal cycling, and high resistance to chemical corrosion. The current candidate materials for such structures are ferritic and ferritic-martensitic steels due to their strong resistance to swelling, good microstructural stability under irradiation, and the retention of adequate ductility at typical reactor operating temperatures.

In parallel, lead bismuth eutectic (LBE) has emerged as a potential spallation target material for efficient production of neutrons, as well as a coolant in the accelerator system. While LBE has excellent properties as a nuclear coolant, it is also highly corrosive …