Determination of Residual Stresses due to Girth-Butt Welds in Pipes

1985 ◽  
Vol 107 (2) ◽  
pp. 178-184 ◽  
Author(s):  
U. Chandra
Keyword(s):  
Residual Stresses ◽  
Experimental Studies ◽  
Thermal Processes ◽  
X Ray Diffraction ◽  
Butt Welds ◽  
Numerical Finite Element ◽  
Primary Focus ◽  
Analytical Category ◽  
Considerable Detail

A state-of-the-art review of analytical and experimental determination of residual stresses due to girth-butt welds in pipes is presented. In the analytical category, closed-form as well as numerical (finite element) solutions are discussed in considerable detail. The results of the experimental studies, with primary focus on the X-ray diffraction (XRD) technique, are highlighted. The effects of process and geometric parameters and of various thermal processes in controlling the tensile residual stress on the pipe inner surface are also reviewed.

X-Ray Diffraction Analysis of Steel with Oxidised Surface Layer

2016 ◽  
Vol 368 ◽  
pp. 99-102
Author(s):  
Lukáš Zuzánek ◽  
Ondřej Řidký ◽  
Nikolaj Ganev ◽  
Kamil Kolařík
Keyword(s):  
Residual Stress ◽  
Surface Layer ◽  
Residual Stresses ◽  
Diffraction Analysis ◽  
Oxide Surface ◽  
X Ray Diffraction ◽  
X Ray ◽  
Electrolytic Polishing ◽  
Small Depth

The basic principle of the X-ray diffraction analysis is based on the determination of components of residual stresses. They are determined on the basis of the change in the distance between atomic planes. The method is limited by a relatively small depth in which the X-ray beam penetrates into the analysed materials. For determination of residual stresses in the surface layer the X-ray diffraction and electrolytic polishing has to be combined. The article is deals with the determination of residual stress and real material structure of a laser-welded steel sample with an oxide surface layer. This surface layer is created during the rolling and it prevents the material from its corrosion. Before the X-ray diffraction analysis can be performed, this surface layer has to be removed. This surface layer cannot be removed with the help of electrolytic polishing and, therefore, it has to be removed mechanically. This mechanical procedure creates “technological” residual stress in the surface layer. This additional residual stress is removed by the electrolytic polishing in the depth between 20 and 80 μm. Finally, the real structure and residual stresses can be determined by using the X-ray diffraction techniques.

Determination of the Residual Stress Field around Scratches Using Synchrotron X-Rays and Nanoindentation

2010 ◽  
Vol 652 ◽  
pp. 25-30
Author(s):  
M.K. Khan ◽  
Michael E. Fitzpatrick ◽  
L.E. Edwards ◽  
S.V. Hainsworth
Keyword(s):  
Residual Stress ◽  
Stress Field ◽  
Residual Stresses ◽  
Small Scale ◽  
X Rays ◽  
X Ray Diffraction ◽  
Residual Stress Field ◽  
Fine Grained ◽  
Load Displacement

The residual strain field around the scratches of 125µm depth and 5µm root radius have been measured from the Synchrotron X-ray diffraction. Scratches were produced using different tools in fine-grained aluminium alloy AA 5091. Residual stresses up to +1700 micro-strains were measured at the scratch tip for one tool but remained up to only +1000 micro-strains for the other tool scratch. The load-displacement curves obtained from nanoindentation were used to determine the residual stresses around the scratches. It was found that the load-displacement curves are sensitive to any local residual stress field present and behave according to the type of residual stresses. This combination of nanoindentation and synchrotron X-rays has been proved highly effective for the study of small-scale residual stresses around the features such as scratches.

Residual Stress Analysis in Containers for Transport of Radioactive Materials

2015 ◽  
Vol 732 ◽  
pp. 28-31 ◽  
Author(s):  
František Trebuňa ◽  
František Šimčák ◽  
Miroslav Pástor ◽  
Patrik Šarga
Keyword(s):  
Residual Stresses ◽  
Experimental Methods ◽  
Hole Drilling ◽  
Thermal Processes ◽  
Safe Operation ◽  
Radioactive Materials ◽  
Hole Drilling Method ◽  
Drilling Method ◽  
Residual Stress Analysis

During verification of safe operation of containers for radioactive waste is possible to use analytical, numerical and experimental methods of mechanics. Determination of residual stresses was one part of analysis. The residual stresses in container body can be induced during their production, overloading during operation, radiation or by thermal processes. In the paper are presented results from analysis of residual stresses in containers by using strain-gage hole-drilling method.

scholarly journals Generalised Least-squares Determination of Triaxial Stress States by X-ray Diffraction and the Associated Errors

1988 ◽  
Vol 41 (2) ◽  
pp. 189 ◽  
Author(s):  
RA Winholtz ◽  
JB Cohen
Keyword(s):  
Stress State ◽  
Residual Stresses ◽  
Least Squares ◽  
Triaxial Stress ◽  
X Ray Diffraction ◽  
Triaxial Stress State ◽  
X Ray ◽  
Stress States ◽  
Counting Statistics

The determination of residual stresses via X-ray diffraction is briefly reviewed, with particular emphasis on the triaxial stress state. A new method is proposed for determining the general stress tensor, which considerably reduces the variances of the stresses due to counting statistics and gradients. The procedure involves a generalised least-squares solution of strains measured at various tilts of the X-ray beam to the sample, and a new set of tilts is recommended to minimise these errors.

scholarly journals Precision X-Ray Stress Analysis of Uranium and Zirconium

1959 ◽  
Vol 3 ◽  
pp. 331-336
Author(s):  
B. J. Wooden ◽  
Lt. E. C. House ◽  
R. E. Ogilvie
Keyword(s):  
Residual Stresses ◽  
Stress Analysis ◽  
Peak Position ◽  
Diffraction Peak ◽  
X Ray Diffraction ◽  
X Ray ◽  
Least Squares Fit ◽  
Order Polynomial ◽  
Desk Calculator

AbstractThe feasibility of using X-ray diffraction methods to measure residual stresses in uranium and zirconium (Zircaloy-2) was investigated. A precision method was developed for the determination of diffraction peak positions and the precision associated therewith. The statistical tables of Fisher and Yates were used to determine what order polynomial provided the best least squares fit within the known precision of the observed data. It was found that a second-order polynomial provided an adequate regression. With the aid of a desk calculator less than 5 min calculation time is required to determine the peak position to a precision of ±0.01°.The stress constant for uranium was determined to be 1308 ± 110 psi/0.01° shift in Δ2θ for copper radiation on the (116) planes at 2θ = 158.3°. The stress constant for Zircaloy-2 was determined to be 430 ± 1 psi/0.01° shift in Δ2θ for chromium radiation on the (10,4) planes at 2θ = 156.4°.

scholarly journals Computational Studies to Identify Potential Main Protease Inhibitors for SARS-CoV-2

2020 ◽  
Author(s):  
M. Elizabeth Sobhia ◽  
Ketan Ghosh ◽  
Srikanth Sivangula ◽  
Harmanpreet Singh ◽  
Siva Kumar
Keyword(s):  
In Silico ◽  
Experimental Studies ◽  
Binding Pocket ◽  
Vital Role ◽  
Active Site Residues ◽  
X Ray Diffraction ◽  
Main Protease ◽  
Docking Protocol ◽  
In Silico Studies

The Coronavirus pandemic has put the entire humanity in total shock and has forced the world to go under total lockdown. It is time for the entire scientific community across the globe to find a solution for this deadly and unseen enemy. In silico studies play a vital role in situations like this, as experimental studies are not feasible by all researchers particularly with relevance to BSL4 procedures. In this study, using the high resolution crystal structure of SARS-CoV-2 main protease (PDB: 5R82), we have identified molecules which can potentially inhibit the main protease (Mpro). We used a three-tier docking protocol making use of three different databases. We analysed the residues which are lying near the ligand binding pocket of the main protease structure and it shows a wide cavity, which can accommodate chemically diverse ligands, occupying different sub-pockets. Using the small fragment bound in the 5R82, we have identified several larger molecules whose functional groups make interactions with the active site residues covering. This study also presumably steers the structure determination of many ligand-main protease complexes using x- ray diffraction methods. These molecules can be used as ‘in silico leads’ and further be explored in the development of SARS-CoV-2 drugs.

scholarly journals Computational Studies to Identify Potential Main Protease Inhibitors for SARS-CoV-2

2020 ◽  
Author(s):  
M. Elizabeth Sobhia ◽  
Ketan Ghosh ◽  
Srikanth Sivangula ◽  
Harmanpreet Singh ◽  
Siva Kumar
Keyword(s):  
In Silico ◽  
Experimental Studies ◽  
Binding Pocket ◽  
Vital Role ◽  
Active Site Residues ◽  
X Ray Diffraction ◽  
Main Protease ◽  
Docking Protocol ◽  
In Silico Studies

The Coronavirus pandemic has put the entire humanity in total shock and has forced the world to go under total lockdown. It is time for the entire scientific community across the globe to find a solution for this deadly and unseen enemy. In silico studies play a vital role in situations like this, as experimental studies are not feasible by all researchers particularly with relevance to BSL4 procedures. In this study, using the high resolution crystal structure of SARS-CoV-2 main protease (PDB: 5R82), we have identified molecules which can potentially inhibit the main protease (Mpro). We used a three-tier docking protocol making use of three different databases. We analysed the residues which are lying near the ligand binding pocket of the main protease structure and it shows a wide cavity, which can accommodate chemically diverse ligands, occupying different sub-pockets. Using the small fragment bound in the 5R82, we have identified several larger molecules whose functional groups make interactions with the active site residues covering. This study also presumably steers the structure determination of many ligand-main protease complexes using x- ray diffraction methods. These molecules can be used as ‘in silico leads’ and further be explored in the development of SARS-CoV-2 drugs.

scholarly journals Numerical Analysis and Experimental Studies on the Residual Stress of W/2024Al Composites

Materials ◽  
2019 ◽  
Vol 12 (17) ◽  
pp. 2746 ◽  
Author(s):  
Guosong Zhang ◽  
Changhui Mao ◽  
Jian Wang ◽  
Ning Fan ◽  
Tiantian Guo
Keyword(s):  
Residual Stress ◽  
Numerical Analysis ◽  
Residual Stresses ◽  
Experimental Studies ◽  
High Strength ◽  
Radiation Shielding ◽  
X Ray Diffraction ◽  
Transfer Coefficients ◽  
Medium Temperature ◽  
Heat Transfer Coefficients

W/2024Al composites can be used for radiation shielding with desirable mechanical properties such as high strength, excellent corrosion resistance, and low density. The quench-induced residual stresses in W/2024Al composites were studied by experimental measurements and numerical analysis using ABAQUS software. Due to the accurate calculation of heat transfer coefficients and the established constitutive equation for description of the variation of yield stress at elevated temperature with different strain rates, the prediction of residual stresses in as-quenched composite blocks achieved by finite element method (FEM) is reliable. Moreover, X-ray diffraction and crack-compliance method were carried out to measure the stresses that developed at the surface and interior of the composites to validate the simulation results. Quenching residual stresses of composite blocks were investigated by taking the influence of quenching medium temperature into consideration. In addition, a comparative study on residual stress magnitudes of as-quenched 2024Al and W/2024Al composites was conducted, and the results show that stress magnitudes of W/2024Al composites are lower than that of 2024Al due to lower thermal gradients during the quenching process.

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