Texture Measurement Techniques for Zircaloy Cladding: A Round-Robin Study

2009 ◽  
pp. 39-39-22 ◽  
Author(s):  
JE Lewis ◽  
G Schoenberger ◽  
RB Adamson
Keyword(s):  
Measurement Techniques ◽  
Round Robin ◽  
Texture Measurement

Problems in the Averaging of Neutron Diffraction Stress Data from Round-Robin Campaigns

2008 ◽  
Vol 571-572 ◽  
pp. 283-288 ◽  
Author(s):  
Robert C. Wimpory ◽  
Carsten Ohms ◽  
Michael Hofmann ◽  
Rainer Schneider ◽  
A.G. Youtsos
Keyword(s):  
Residual Stress ◽  
Neutron Diffraction ◽  
Measurement Techniques ◽  
Measurement Data ◽  
Systematic Errors ◽  
Round Robin ◽  
Error Bar ◽  
Data Points ◽  
Outlier Data ◽  
Few Data

In recent years the use of a special Bayesian approach on averaging ‘round-robin’ residual stress data has been implemented. This averaging approach is useful in that it copes with the situation where systematic errors have occurred in one or more of the measurements and thus diminishes the influence of these particular ‘wrong value’ outlier data points. The analyses not only take into account the measurand value, but also the uncertainties associated with each measurand. It should deal with data that may contain individual members with uncertainties larger than the stated error and assumes that the quoted error bar is only a lower bound on the uncertainty. This work shows what could happen when there is a ‘strong mismatch’ in uncertainties when averaging over a limited amount of data. It has been observed that in a case where there are few data points (for example 5 or less), a strong bias can occur towards data points with a relatively small quoted uncertainty compared to other data points with larger quoted uncertainties. A ‘mismatch’ in uncertainty quotation can arise when averaging very good data with poorer data or when averaging with data obtained from other measurement techniques. This effect is demonstrated in this work by using fictitious data and also based on the example of real measurement data obtained by neutron diffraction.

scholarly journals Some Considerations about the Use of Contact and Confocal Microscopy Methods in Surface Texture Measurement

Materials ◽  
2018 ◽  
Vol 11 (8) ◽  
pp. 1484 ◽  
Author(s):  
Jesús Caja García ◽  
Alfredo Sanz Lobera ◽  
Piera Maresca ◽  
Teresa Fernández Pareja ◽  
Chen Wang
Keyword(s):  
Measurement Techniques ◽  
Horizontal Resolution ◽  
Measurement Precision ◽  
Point Of View ◽  
Surface Metrology ◽  
Roughness Parameters ◽  
Reliable Measurement ◽  
Texture Measurement ◽  
Complexity Of Algorithms ◽  
Parameters Calculation

Surface metrology employs various measurement techniques, among which there has been an increase of noteworthy research into non-contact optical and contact stylus methods. However, some deeper considerations about their differentiation and compatibility are still lacking and necessary. This work compares the measurement characteristics of the confocal microscope with the portable stylus profilometer instrumentation, from a metrological point of view (measurement precision and accuracy, and complexity of algorithms for data processing) and an operational view (measuring ranges, measurement speed, environmental and operational requirements, and cost). Mathematical models and algorithms for roughness parameters calculation and their associated uncertainties evaluation are developed and validated. The experimental results demonstrate that the stylus profilometer presents the most reliable measurement with the highest measurement speed and the least complex algorithms, while the image confocal method takes advantage of higher vertical and horizontal resolution when compared with the employed stylus profilometer.

Defect Analysis of Rapid Thermal Processing Round Robin Results

1989 ◽  
Vol 146 ◽  
Author(s):  
C. B. Yarling ◽  
W.A. Keenan
Keyword(s):  
Sheet Resistance ◽  
Measurement System ◽  
Thermal Wave ◽  
Measurement Techniques ◽  
Round Robin ◽  
High Dose ◽  
Wave Measurement ◽  
Thermal Wave Measurement ◽  
Laser Probes ◽  
Flatness Measurement

ABSTRACTThe Greater Silicon Valley Implant Users' Group (GSVIUG) has conducted a round robin to determine the uniformity and repeatability available in wafers processed with modern RTP equipment. High-dose ion implantation (As, 5E15, 80keV) of 150mm wafers was used to monitor temperature distribution through sheet resistance. Sheet resistance maps were then used to compare the uniformity and repeatability of each vendor. As previously reported, the actual uniformity results varied significantly with RTP vendor and implant conditions, ranging from 0.77% (one sigma/mean) to 3.55%. In addition, some contour patterns were quite representative of specific vendors.Subsequently, wafers from each participating vendor were evaluated by three techniques in order to determine what damage or defects might have resulted from the RTP process: laser flatness measurement, optical-imaging inspection, and thermal wave measurement. The flatness measurement system was used to measure the warpage of each sample. The reflective-optical inspection technique is a full-field, non-destructive technique that provides a real-time visual display, evidenced by light and dark field contrast over the entire wafer. The thermal wave measurement system uses two laser probes to measure a difference in modulated reflectance which results from damage or defects within the wafer.This paper describes each of the three techniques and summarizes the measured results of wafer defects and damage due to the processing by various RTP vendors. Comparisons between the three measurement techniques are made.

scholarly journals Die waarneming van luiheid as basis vir die meting van geraassteuring en produktiwiteit: 'n Internasionale ondersoek

1976 ◽  
Author(s):  
A. J. Van Wyk
Keyword(s):  
Cultural Differences ◽  
High Intensity ◽  
Measurement Techniques ◽  
National Level ◽  
Human Perception ◽  
Round Robin ◽  
Noise Measurement ◽  
Calculation Methods ◽  
Research Results ◽  
International Round

Human perception of loudness is considered the basis for noise measurement techniques. Due to the use of 18 different internationally accepted calculation methods which lead to much confusion, an International Round Robin project was organized for the evaluation of these methods under uniform conditions. The Stevens method proved to be the best overall simulation of human perception of loudness while the Zwicker and PNdB methods produced the best results at low and high intensity levels respectively. It was furthermore concluded that cultural differences between various participating groups had no significant effect on the perception of loudness. Research results obtained at national level can therefore be projected on international standards.Opsomming Mensike waarneming van luidheid word as basis van geraasmeetmetodes beskou. As gevolg van die verwarring en - probleme wat by die gebruik van soveel as 18 internasionaal erkende meetmetodes vir geraas bestaan is 'n wêreldwye ondersoek organiseer waarin hierdie meetmetodes onder eenvormige toestande onderling vergelyk is. Die Stevens-metode word bevind die beste algemene simuleerder van menslike waarneming van luidheid te wees terwyl die Zwicker-metode op lae intensiteitspeile en die PNdB-metode op hoë intensiteitspeile goeie resultate lewer. Geen kulturele verskille tussen groepe toetslinge ten opsigte van luidheidswaarneming word identifiseer nie wat dus nasionale navorsing geprojekteer op internasionale standaarde wetenskaplik regverdig.

scholarly journals Recommendations for the measurement of residual stresses in welded joints by means of X-ray diffraction—results of the WG6-RR test

2020 ◽  
Author(s):  
Th. Nitschke-Pagel
Keyword(s):  
Residual Stresses ◽  
Boundary Conditions ◽  
Welded Joints ◽  
High Reliability ◽  
Measurement Techniques ◽  
Round Robin ◽  
X Ray Diffraction ◽  
Round Robin Test ◽  
X Ray

AbstractResidual stresses in welded joints are often of extended interest in order to evaluate unexpected failures or distortions. Since the possibilities to calculate residual stresses in welds are still strongly limited, the measurement techniques are still of great importance. Several measurement techniques with particular possibilities and limitations are available today where especially the different diffraction methods are used mostly. The material, weld type, and the size of the components are important for the quality of the results obtained with different methods as well as the environment where the measurements have to be carried out. The paper shall give an overview of the results of a round robin test on the application of XRD on butt welded joints which has been carried out in cooperation of different experienced laboratories. The results show the high reliability of XRD measurements in welds, if the measurements are performed under well-defined boundary conditions. The experiences can be used as a recommendation about useful measurement conditions the expectable quality of the results.

Analysis of Zirconia Powder for Thermal Spray: Reference Material for Particle Size Distribution Measurement

1996 ◽  
Author(s):  
P. Pei ◽  
J. Kelly ◽  
S. Malghan ◽  
S. Dapkunas
Keyword(s):  
Particle Size ◽  
Light Scattering ◽  
Reference Material ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Thermal Spray ◽  
Measurement Techniques ◽  
Round Robin ◽  
Ease Of Use ◽  
Scattering Method

Abstract The thermal spray industry identified the need for repeatable and reproducible feedstock powder characterization methods, especially particle size distribution (PSD), for cost effective manufacturing of thermal barrier coatings. The PSD measurement by a laser light scattering method was identified as the technique most widely used in the industry. This technique offers high resolution, rapid measurements and ease of use. A round robin study by nine laboratories using different models of a commercial light scattering instrument has been completed as the first step towards the development of a Standard Reference Material (SRM) for the calibration of light scattering instrument. Other measurement techniques were also employed for additional comparison. The PSD measurements employing light scattering techniques evidenced some method dependence, despite the use of identical sample preparation procedures. The round robin results will serve as reference values for the development of the SRM.

Reference Coordinate System Requirements for Geophysics

1975 ◽  
Vol 26 ◽  
pp. 87-92
Author(s):  
P. L. Bender
Keyword(s):  
Coordinate System ◽  
Polar Motion ◽  
Main Part ◽  
Measurement Techniques ◽  
Reference Points ◽  
Angular Motion ◽  
Coordinate Systems ◽  
Axis Of Rotation ◽  
The Earth ◽  
Fixed System

AbstractFive important geodynamical quantities which are closely linked are: 1) motions of points on the Earth’s surface; 2)polar motion; 3) changes in UT1-UTC; 4) nutation; and 5) motion of the geocenter. For each of these we expect to achieve measurements in the near future which have an accuracy of 1 to 3 cm or 0.3 to 1 milliarcsec.From a metrological point of view, one can say simply: “Measure each quantity against whichever coordinate system you can make the most accurate measurements with respect to”. I believe that this statement should serve as a guiding principle for the recommendations of the colloquium. However, it also is important that the coordinate systems help to provide a clear separation between the different phenomena of interest, and correspond closely to the conceptual definitions in terms of which geophysicists think about the phenomena.In any discussion of angular motion in space, both a “body-fixed” system and a “space-fixed” system are used. Some relevant types of coordinate systems, reference directions, or reference points which have been considered are: 1) celestial systems based on optical star catalogs, distant galaxies, radio source catalogs, or the Moon and inner planets; 2) the Earth’s axis of rotation, which defines a line through the Earth as well as a celestial reference direction; 3) the geocenter; and 4) “quasi-Earth-fixed” coordinate systems.When a geophysicists discusses UT1 and polar motion, he usually is thinking of the angular motion of the main part of the mantle with respect to an inertial frame and to the direction of the spin axis. Since the velocities of relative motion in most of the mantle are expectd to be extremely small, even if “substantial” deep convection is occurring, the conceptual “quasi-Earth-fixed” reference frame seems well defined. Methods for realizing a close approximation to this frame fortunately exist. Hopefully, this colloquium will recommend procedures for establishing and maintaining such a system for use in geodynamics. Motion of points on the Earth’s surface and of the geocenter can be measured against such a system with the full accuracy of the new techniques.The situation with respect to celestial reference frames is different. The various measurement techniques give changes in the orientation of the Earth, relative to different systems, so that we would like to know the relative motions of the systems in order to compare the results. However, there does not appear to be a need for defining any new system. Subjective figures of merit for the various system dependon both the accuracy with which measurements can be made against them and the degree to which they can be related to inertial systems.The main coordinate system requirement related to the 5 geodynamic quantities discussed in this talk is thus for the establishment and maintenance of a “quasi-Earth-fixed” coordinate system which closely approximates the motion of the main part of the mantle. Changes in the orientation of this system with respect to the various celestial systems can be determined by both the new and the conventional techniques, provided that some knowledge of changes in the local vertical is available. Changes in the axis of rotation and in the geocenter with respect to this system also can be obtained, as well as measurements of nutation.

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