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Development Of A Mechanistic Understanding Of High-Temperature Deformation Of Alloy Ep-823 For Transmutation Applications: Quarterly Progress Report (June 01 – Aug 31, 2003), Ajit K. Roy, Brendan O'Toole

Transmutation Sciences Materials (TRP)

The purpose of this project is to evaluate the elevated temperature tensile properties of Alloy EP-823, a leading target material for accelerator-driven waste transmutation applications. This Alloy has been proven to be an excellent structural material to contain the lead-bismuth-eutectic (LBE) nuclear coolant needed for fast spectrum operations. Very little data exist in the open literature on the tensile properties of this Alloy. The test material will be thermally treated prior to the evaluation of its tensile properties at temperatures relevant to the transmutation applications. The deformation characteristics of tensile specimens, upon completion of testing, will be evaluated by surface …

Use Of Positron Annihilation Spectroscopy For Stress-Strain Measurements: Quarterly Progress Report (June 01 – August 31, 2003), Ajit K. Roy

Transmutation Sciences Materials (TRP)

The purpose of this collaborative research project involving the University of Nevada Las Vegas (UNLV), the Idaho State University (ISU), and the Los Alamos National Laboratory (LANL) is to evaluate the feasibility of determining residual stresses in cold-worked, plastically-deformed (bent), and welded materials using a nondestructive method based on positron annihilation spectroscopy (PAS). This technique uses γ-rays from a small MeV electron Linac to generate positrons inside the sample via pair production. This method is known to have capabilities of characterizing defects in thick specimens that could not be accomplished by conventional positron technique or other nondestructive methods. The generated …

Development Of A Mechanistic Understanding Of High-Temperature Deformation Of Alloy Ep-823 For Transmutation Applications: Annual Progress Report (September 2002 – August 2003), Ajit K. Roy, Brendan O'Toole

Transmutation Sciences Materials (TRP)

The purpose of this project is to evaluate the elevated temperature tensile properties of Alloy EP-823, a leading structural target material for accelerator-driven waste transmutation applications. This alloy has been proven to be an excellent structural material to contain the molten lead-bismuth-eutectic (LBE) nuclear coolant needed for fast spectrum operations. Very little data exist in the open literature on the tensile properties of this martensitic alloy. Three different heats of this material, produced by vacuum induction melting, were thermally treated to produce fully-tempered martensitic microstructure without any retained austenite (Table I). Cylindrical specimens were fabricated from the heat-treated round bars …

Modeling Corrosion In Oxygen Controlled Lbe Systems With Coupling Of Chemical Kinetics And Hydrodynamics-Task V: Annual Report -Phase Ii 09/01/2002-08/30/2003, Samir Moujaes, Yitung Chen

Transmutation Sciences Materials (TRP)

The Lead-Bismuth eutectic (LBE) has been determined from previous experimental studies by the Russians and the European scientific community to be a potential material that can be used as a spallation target and coolant for the TRP proposed application. Properly controlling the oxygen content in LBE can drastically reduce the LBE corrosion to structural steels. However, existing knowledge of material corrosion performance was obtained from point-wise testing with only very sparse experimental data. Scientists have noticed that the concentration of oxygen dissolved in the liquid alloy could control the corrosion rate of steels exposed to Pb or Pb-Bi. At high …

Use Of Positron Annihilation Spectroscopy For Stress-Strain Measurements: Annual Progress Report (May 2002 – May 2003), Ajit K. Roy

Transmutation Sciences Materials (TRP)

The purpose of this collaborative research project involving the University of Nevada Las Vegas (UNLV) and Idaho State University (ISU) to evaluate the feasibility of determining residual stresses of welded, bent (three-point-bend), and cold-worked engineering materials using a new non-destructive technique based on positron annihilation spectroscopy. The proposed technique is the use γ-rays from a small MeV electron Linear accelerator (LINAC) to generate positrons inside the sample via pair production. This method can be used for materials characterization and investigation of defects in thick samples, which could not be accomplished by conventional positron technique or other non-destructive methods. The data …

Development Of A Mechanistic Understanding Of High-Temperature Deformation Of Alloy Ep-823 For Transmutation Applications Trp Task-10: Quarterly Progress Report (March 01 – May 31, 2003), Ajit K. Roy, Brendan O'Toole

Transmutation Sciences Materials (TRP)

The purpose of this project is to evaluate the elevated temperature tensile properties of Alloy EP- 823, a leading target material for accelerator-driven waste transmutation applications. This alloy has been proven to be an excellent structural material to contain the lead-bismuth-eutectic (LBE) nuclear coolant needed for fast spectrum operations. Very little data exist in the open literature on the tensile properties of this alloy. The test material will be thermally treated prior to the evaluation of its tensile properties at temperatures relevant to the transmutation applications. The deformation characteristics of tensile specimens, upon completion of testing, will be evaluated by …

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

Transmutation Sciences Materials (TRP)

The purpose of this project is to evaluate the elevated temperature tensile properties of Alloy EP-823, a leading target material for accelerator-driven waste transmutation applications. This alloy has been proven to be an excellent structural material to contain the lead-bismuth-eutectic (LBE) nuclear coolant needed for fast spectrum operations. However, very little data exist in the open literature on the tensile properties of this alloy. The selection of Alloy EP-823 as the test material in the proposed task is based on the recommendation of our collaborator at the Los Alamos National Laboratory (LANL). The test material will be thermally treated prior …

Use Of Positron Annihilation Spectroscopy For Stress-Strain Measurements, Ajit K. Roy

Transmutation Sciences Materials (TRP)

The purpose of this collaborative research project involving the University of Nevada, Las Vegas (UNLV) and the Idaho State University (ISU) is to evaluate the feasibility of determining residual stresses of welded, bent (three-point-bend), and cold-worked engineering materials using a new nondestructive technique based on positron annihilation spectroscopy. The proposed technique is to use x-rays from a small MeV electron Linac to generate positrons inside the sample via pair production. This method can be used for materials characterization and investigation of defects in thick samples that could not be accomplished by conventional positron technique or other nondestructive methods. The data …

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. …

Modeling Of Corrosion In Oxygen Controlled Lead Bismuth Eutectic Systems With The Coupling Of Chemical Kinetics And Hydrodynamics, Samir Moujaes, Yitung Chen, Kanthi Kiran Dasika, Chao Wu

Transmutation Sciences Materials (TRP)

Objectives:

• To simulate a 2-D model of the Materials Test Loop by approximating it to be a toroid with a pie cross section for the purpose of comparing the simulated results with the analytical results.
• The temperature and concentration profiles on the wall boundaries imposed are similar to the actual test model.
• Geometry effects have great influence on local corrosion rate.
• A 2-D benchmark problem and a sudden expansion case are studied which show good consistency to analytical solution.
• Results from 2-D sudden expansion problem are similar to experimental data obtained by other researchers.

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

Transmutation Sciences Materials (TRP)

The purpose of this task is to evaluate the mechanical properties of Alloy EP-823 at temperatures relevant to the transmutation processes. Testing has been initiated to evaluate the tensile properties of martensitic Alloy EP-823 stainless steel at temperatures ranging from ambient (25 °C) to 600°C. The test materials were thermally treated prior to the evaluation of their tensile properties. The deformation characteristics of these tensile specimens, upon completion of testing, will be evaluated by surface analytical techniques such as scanning electron microscopy (SEM) and transmission electron microscopy (TEM).

Use Of Positron Annihilation Spectroscopy For Stress-Strain Measurements, Ajit K. Roy

Transmutation Sciences Materials (TRP)

One of the greatest challenges in evaluating the performance of materials in the real world is the determination of residual stresses, or the stresses induced in a material. Plastic deformation of metals and alloys produces an increase in the number of lattice imperfections known as dislocations, which by virtue of their interaction results in higher state of internal stress and reduces ductility. These stresses, if not properly annealed (released) can significantly degrade the long-term performance of the materials.

Due to the high temperatures and radiation fields typically encountered in most nuclear systems, such as accelerator-driven transmutation systems (ADS) and nuclear …

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

Transmutation Sciences Materials (TRP)

An innovative research program is proposed to investigate the corrosion of steel by lead alloys, and in particular lead-bismuth eutectic (LBE). In our previous work, some steels were found to be far more resistant to corrosion by LBE than others depending on surface preparation (cold working). This program would allow testing of crucial hypotheses about the causes of the observed increased corrosion resistance. We propose to build a new test facility at UNLV to expose steel samples to LBE as well as facilities to prepare steel samples as indicated by our work.

The unique capabilities of the test system will …