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Neutron Diffraction Residual Strain Tensor Measurements Within The Phase IA Weld Mock-up Plate P-5

Description: Oak Ridge National Laboratory (ORNL) has worked with NRC and EPRI to apply neutron and X-ray diffraction methods to characterize the residual stresses in a number of dissimilar metal weld mockups and samples. The design of the Phase IA specimens aimed to enable stress measurements by several methods and computational modeling of the weld residual stresses. The partial groove in the 304L stainless steel plate was filled with weld beads of Alloy 82. A summary of the weld conditions for each plate is provided in Table 1. The plates were constrained along the long edges during and after welding by bolts with spring-loaded washers attached to the 1-inch thick Al backing plate. The purpose was to avoid stress relief due to bending of the welded stainless steel plate. The neutron diffraction method was one of the methods selected by EPRI for non-destructive through thickness strain and stress measurement. Four different plates (P-3 to P-6) were studied by neutron diffraction strain mapping, representing four different welding conditions. Through thickness neutron diffraction strain mappings at NRSF2 for the four plates and associated strain-free d-zero specimens involved measurement along seven lines across the weld and at six to seven depths. The mountings of each plate for neutron diffraction measurements were such that the diffraction vector was parallel to each of the three primary orthogonal directions of the plate: two in-plane directions, longitudinal and transverse, and the direction normal to the plate (shown in left figure within Table 1). From the three orthogonal strains for each location, the residual stresses along the three plate directions were calculated. The principal axes of the strain and stress tensors, however, need not necessarily align with the plate coordinate system. To explore this, plate P-5 was selected for examination of the possibility that the principal axes of strain ...
Date: September 1, 2011
Creator: Hubbard, Camden R
Partner: UNT Libraries Government Documents Department

Calibration of NRSF2 Instrument at HFIR

Description: The Neutron Residual Stress Mapping Facility (NRSF2) at HB-2B is a new generation-diffraction instrument, adding many new Second Generation features, such as larger beam tube, large sample XYZ goniometer, and KAPPA orienter for a broad range of materials behavior studies. One key feature is the NRSF2 monochromator, which is a double focusing, double crystal monochromator system consisting of two sets of stacked Si crystal wafers. One set of wafers has Si[400] plane normal to the surface while the other set of wafers has the Si[500] normal to the surface. The monochromator crystal diffracts at a fixed diffraction angle of 88{sup o} selecting a neutron wavelength determined by the monochromator d{sub hkl}-spacing. This 'Missouri' monochromator system has two independent monochromators, which enable diffraction from the following set of six diffraction planes: Si(511), Si(422), Si(331)AF (Anti-Fankuchen geometry), Si(400), Si(311), and Si(220). These diffraction planes can provide 6 different neutron wavelengths: approximately 1.45, 1.54, 1.73, 1.89 {angstrom}, 2.27, and 2.66 also incorporate seven position sensitive detectors located in a detector shield box. To use this advanced instrument for scientific and engineering measurements, careful calibration needs to be performed to accurately calibrate the seven position sensitive detectors, neutron wavelength, and 2{theta}{sub 0}. Just as in the X-ray diffraction technique, neutron diffraction directly measures the diffraction angle (2{theta}) or diffraction peak position, then based on Bragg's law and a strain free lattice spacing, the strain can be calculated. Therefore anything that can affect the diffracting angle measurement can influence the accuracy of the strain measurements. The sources of difficulties in achieving accurate neutron diffraction peak positions can be classified into three categories. (1) Instrument - These difficulties come from alignment of the monochromator, alignment of the incident and detector slits, leveling of the sample table, 2{theta}{sub 0} offset, and response of the position sensitive detector; ...
Date: August 1, 2006
Creator: Tang, Fei & Hubbard, Camden R
Partner: UNT Libraries Government Documents Department

Laboratory Guide for Residual Stress Sample Alignment and Experiment Planning-October 2011 Version

Description: The December 2010 version of the guide, ORNL/TM-2008/159, by Jeff Bunn, Josh Schmidlin, Camden Hubbard, and Paris Cornwell, has been further revised due to a major change in the GeoMagic Studio software for constructing a surface model. The Studio software update also includes a plug-in module to operate the FARO Scan Arm. Other revisions for clarity were also made. The purpose of this revision document is to guide the reader through the process of laser alignment used by NRSF2 at HFIR and VULCAN at SNS. This system was created to increase the spatial accuracy of the measurement points in a sample, reduce the use of neutron time used for alignment, improve experiment planning, and reduce operator error. The need for spatial resolution has been driven by the reduction in gauge volumes to the sub-millimeter level, steep strain gradients in some samples, and requests to mount multiple samples within a few days for relating data from each sample to a common sample coordinate system. The first step in this process involves mounting the sample on an indexer table in a laboratory set up for offline sample mounting and alignment in the same manner it would be mounted at either instrument. In the shared laboratory, a FARO ScanArm is used to measure the coordinates of points on the sample surface ('point cloud'), specific features and fiducial points. A Sample Coordinate System (SCS) needs to be established first. This is an advantage of the technique because the SCS can be defined in such a way to facilitate simple definition of measurement points within the sample. Next, samples are typically mounted to a frame of 80/20 and fiducial points are attached to the sample or frame then measured in the established sample coordinate system. The laser scan probe on the ScanArm can then be ...
Date: April 1, 2012
Creator: Cornwell, Paris A; Bunn, Jeffrey R; Schmidlin, Joshua E & Hubbard, Camden R
Partner: UNT Libraries Government Documents Department

Standard X-ray Diffraction Powder Patterns: Section 12. Data for 57 Substances

Description: From Introduction: "This report presents information for 57 compounds (25 experimental and 32 calculated patterns), and is the two-second of the series of "Standard x-ray Diffraction Powder Patterns."
Date: February 1975
Creator: McMurdie, Howard F.; Morris, Marlene C.; Evans, Eloise H.; Paretzkin, Boris; de Groot, Johan H.; Hubbard, Camden R. et al.
Partner: UNT Libraries Government Documents Department

Standard X-ray Diffraction Powder Patterns: Section 13. Data for 58 substances

Description: From Introduction: "This report presents information for 58 compounds (31 experimental and 27 calculated patterns), and is the twenty-third of the series of "Standard X-ray Diffraction Powder Patterns."
Date: June 1976
Creator: Morris, Marlene C.; McMurdie, Howard F.; Evans, Eloise H.; Paretzkin, Boris; de Groot, Johan H.; Hubbard, Camden R. et al.
Partner: UNT Libraries Government Documents Department

Standard X-ray Diffraction Powder Patterns: Section 17. Data for 54 Substances

Description: From Introduction: "This report presents information for 54 experimental patterns, and is the twenty-seventh of the series of Standard X-ray Diffraction Powder Patterns."
Date: October 1980
Creator: Morris, Marlene C.; McMurdie, Howard F.; Evans, Eloise H.; Paretzkin, Boris; Hubbard, Camden R. & Carmel, Simon J.
Partner: UNT Libraries Government Documents Department

Standard X-ray Diffraction Powder Patterns: Section 18. Data for 58 Substances

Description: From Introduction: "This report presents information for 58 experimental patterns, and is the twenty-eighth of the series of Standard X-ray Diffraction Powder Patterns."
Date: October 1981
Creator: Morris, Marlene C.; McMurdie, Howard F.; Evans, Eloise H.; Paretzkin, Boris; Parker, Harry S.; Panagiotopoulos, Nicolas C. et al.
Partner: UNT Libraries Government Documents Department

Standard X-ray Diffraction Powder Patterns: Section 14. Data for 68 substances

Description: From Introduction: "This report presents information for 68 compounds (27 experimental and 41 calculated patterns), and is the twenty-fourth of the series of "Standard x-ray Diffraction Powder Patterns."
Date: September 1977
Creator: Morris, Marlene C.; McMurdie, Howard F.; Evans, Eloise H.; Paretzkin, Boris; de Groot, Johan H.; Newberry, Rainer et al.
Partner: UNT Libraries Government Documents Department

Standard X-ray Diffraction Powder Patterns : Section 16. Data for 86 Substances

Description: From Introduction: "This report presents information for 86 compounds (58 experimental and 28 calculated patterns), and is the twenty-sixth of the series of "Standard X-ray Diffraction Powder Patterns."
Date: October 1979
Creator: Morris, Marlene C.; McMurdie, Howard F.; Evans, Eloise H.; Paretzkin, Boris; de Groot, Johan H.; Hubbard, Camden R. et al.
Partner: UNT Libraries Government Documents Department

Neutron Radiography and Computed Tomography at Oak Ridge National Laboratory

Description: The capability to perform neutron radiography and computed tomography is being developed at Oak Ridge National Laboratory. The facility will be located at the High Flux Isotope Reactor (HFIR), which has the highest steady state neutron flux of any reactor in the world. The Monte Carlo N-Particle transport code (MCNP), versions 4A and 4B, has been used extensively in the design phase of the facility to predict and optimize the operating characteristics, and to ensure the safety of personnel working in and around the blockhouse. Neutrons are quite penetrating in most engineering materials and can be useful to detect internal flaws and features. Hydrogen atoms, such as in a hydrocarbon fuel, lubricant or a metal hydride, are relatively opaque to neutron transmission. Thus, neutron based tomography or radiography is ideal to image their presence. The source flux also provides unparalleled flexibility for future upgrades, including real time radiography where dynamic processes can be observed. A novel tomography detector has been designed using optical fibers and digital technology to provide a large dynamic range for reconstructions. Film radiography is also available for high resolution imaging applications. This paper summarizes the results of the design phase of this facility and the potential benefits to science and industry.
Date: December 31, 1997
Creator: Raine, Dudley A. III; Hubbard, Camden R.; Whaley, Paul M.; Wright, Michael C. & Hutchinson, Donald P.
Partner: UNT Libraries Government Documents Department

Standard X-ray Diffraction Powder Patterns: Section 15. Data for 112 substances

Description: From Introduction: "This report presents information for 112 compounds (54 experimental and 58 calculated patterns), and is the twenty-fifth of the series of "Standard x-ray Diffraction Powder Patterns."
Date: October 1978
Creator: Morris, Marlene C.; McMurdie, Howard F.; Evans, Eloise H.; Paretzkin, Boris; de Groot, Johan H.; Weeks, Brenda S. et al.
Partner: UNT Libraries Government Documents Department

Cracking and Corrosion of Composite Tubes in Black Liquor Recovery Boiler Primary Air Ports

Description: Black liquor recovery boilers are an essential part of kraft mills. Their design and operating procedures have changed over time with the goal of providing improved boiler performance. These performance improvements are frequently associated with an increase in heat flux and/or operating temperature with a subsequent increase in the demand on structural materials associated with operation at higher temperatures and/or in more corrosive environments. Improvements in structural materials have therefore been required. In most cases the alternate materials have provided acceptable solutions. However, in some cases the alternate materials have solved the original problem but introduced new issues. This report addresses the performance of materials in the tubes forming primary air port openings and, particularly, the problems associated with use of stainless steel clad carbon steel tubes and the solutions that have been identified.
Date: October 1, 2006
Creator: Keiser, James R.; Singbeil, Douglas L.; Sarma, Gorti B.; Kish, Joseph R.; Yuan, Jerry; Frederick, Laurie A. et al.
Partner: UNT Libraries Government Documents Department