Surface Treatment Effect on Measurement of Welding Residual Stress Using X-Ray Stress Analyzer

2013 ◽  
Vol 631-632 ◽  
pp. 617-621 ◽  
Author(s):  
Zhu Wu Zhang ◽  
Qin Yao ◽  
Ai Ping Wu ◽  
Ling Zhu Gong
Keyword(s):  
Residual Stress ◽  
Pressure Vessel ◽  
Measurement Errors ◽  
Scientific Basis ◽  
Welding Residual Stress ◽  
Test Plate ◽  
Welding Seam ◽  
X Ray ◽  
Stress Changes ◽  
Theory Calculation

The effects of welding residual stress (WRS) would be harmful to safety and intensity of pressure vessel. X-ray stress analyzer (XRSA) can be used to non-destructively quantitative analyze WRS. In this study, stress changes of constant stress beam in loading process were tested using strain gauge (SG), strain rosette (SR) and XRSA, and their test results were compared to analyze measurement errors of XRSA. It was found that the property of XRSA meets the experimental requirement. The machining stress in surface of welding test plate could be completely removed after 4 min electrolytic polishing under 1 A current and 100% NaCl electrolyte. The WRS of welding test plate was tested by XRSA after machining stress completely removed, and its distribution along vertical welding seam direction corresponded with theory calculation. Furthermore, XRSA as a non-destructive method will be more used to study WRS of pressure vessel, so these results can provide scientific basis for the studying.

Modification for Quantitative Analysis of Welding Residual Stress by X-Ray Stress Analyzer

2013 ◽  
Vol 302 ◽  
pp. 384-388
Author(s):  
Zhu Wu Zhang ◽  
Qin Yao ◽  
Ai Ping Wu ◽  
Ling Zhu Gong
Keyword(s):  
Residual Stress ◽  
Heat Affected Zone ◽  
Scientific Basis ◽  
Welding Residual Stress ◽  
Welding Seam ◽  
X Ray ◽  
Quantitative Calculation ◽  
Spherical Tank ◽  
Testing Data ◽  
Non Destructive

Welding residual stress (WRS) has been paid more attention because it would be harmful to safety and intensity of spherical tank. X-ray stress analyzer (XRSA) can be used to non-destructively quantitative analyze WRS. In this study, the real values of Young’s module (E) and Poisson’s ratio (ν) of materials were used to quantitatively calculate. The initial θ0 of materials of welding seam, heat-affected zone and base metal (16MnDR) with zero-stress were detected to analyze influence of quantitative calculation. Moreover, ±5° ψ-oscillation was chosen to use in testing process by XRSA to decrease dispersion of testing data due to large grain size in welding seam and heat-affected zone. Furthermore, XRSA as a non-destructive method will be more used to study WRS of spherical tank, so these results can provide scientific basis for the studying.

scholarly journals Diffracting-grain identification from electron backscatter diffraction maps during residual stress measurements: a comparison between the sin2ψ and cosα methods

2019 ◽  
Vol 52 (4) ◽  
pp. 828-843 ◽  
Author(s):  
Dorian Delbergue ◽  
Damien Texier ◽  
Martin Lévesque ◽  
Philippe Bocher
Keyword(s):  
Residual Stress ◽  
Grain Size ◽  
Tilt Angle ◽  
Measurement Errors ◽  
Electron Backscatter Diffraction ◽  
Measurement Techniques ◽  
Single Exposure ◽  
X Ray ◽  
Electron Backscatter ◽  
Backscatter Diffraction

X-ray diffraction (XRD) is a widely used technique to evaluate residual stresses in crystalline materials. Several XRD measurement methods are available. (i) The sin2ψ method, a multiple-exposure technique, uses linear detectors to capture intercepts of the Debye–Scherrer rings, losing the major portion of the diffracting signal. (ii) The cosα method, thanks to the development of compact 2D detectors allowing the entire Debye–Scherrer ring to be captured in a single exposure, is an alternative method for residual stress measurement. The present article compares the two calculation methods in a new manner, by looking at the possible measurement errors related to each method. To this end, sets of grains in diffraction condition were first identified from electron backscatter diffraction (EBSD) mapping of Inconel 718 samples for each XRD calculation method and its associated detector, as each method provides different sets owing to the detector geometry or to the method specificities (such as tilt-angle number or Debye–Scherrer ring division). The X-ray elastic constant (XEC) ½S 2, calculated from EBSD maps for the {311} lattice planes, was determined and compared for the different sets of diffracting grains. It was observed that the 2D detector captures 1.5 times more grains in a single exposure (one tilt angle) than the linear detectors for nine tilt angles. Different XEC mean values were found for the sets of grains from the two XRD techniques/detectors. Grain-size effects were simulated, as well as detector oscillations to overcome them. A bimodal grain-size distribution effect and `artificial' textures introduced by XRD measurement techniques are also discussed.

Study of residual stresses in A7N01 aluminum alloy with X-ray diffraction Debye ring analysis

2019 ◽  
Vol 33 (01n03) ◽  
pp. 1940032 ◽  
Author(s):  
Pengfei Zhu ◽  
Guoqing Gou ◽  
Zhaofu Li ◽  
Minhao Zhu ◽  
Zhongyin Zhu ◽  
...  
Keyword(s):  
Residual Stress ◽  
Aluminum Alloy ◽  
Welded Joints ◽  
Welding Residual Stress ◽  
Test Results ◽  
X Ray Diffraction ◽  
X Ray ◽  
Debye Ring ◽  
Size Stability ◽  
Ring Analysis

The welding residual stress has different effects on the mechanical properties of aluminum alloy welded joints, such as size stability, fatigue strength and stress corrosion cracking. Therefore, it is very important to evaluate the welding residual stress accurately. In this paper, the residual stress of A7N01 aluminum alloy welded joints was measured by X-ray diffraction. In contrast to the traditional method, the cos[Formula: see text] method was used in this paper, the results were compared with those obtained by the conventional [Formula: see text] method. In addition, the influence of oscillation unit on the test results of the cos[Formula: see text] method was studied.

Temperature Field and Residual Stress Analysis of the Gear on CO2 Laser Welding Process

2011 ◽  
Vol 86 ◽  
pp. 670-673
Author(s):  
Jian Luo ◽  
Fei Li ◽  
Ke Liang Xue ◽  
De Jia Liu ◽  
Hai Wei Zhang
Keyword(s):  
Residual Stress ◽  
Temperature Field ◽  
Laser Welding ◽  
Welding Process ◽  
Welding Residual Stress ◽  
Temperature Cycle ◽  
Residual Tensile Stress ◽  
Welding Seam ◽  
Welding Temperature ◽  
Laser Welding Process

The welding technique is one of important technologies on the gear manufacturing process. The special welding temperature cycle is the basic conditions of the welding residual stress appearance in the gear. The large welding residual stress will create the large deformation after the gear welding, which will affect the gear service behavior. In this paper, the finite element method has used to simulate the gear laser welding process. The temperature field and residual stress has described. The research results show that the biggest residual compressive stress appears on the transverse direction of welding region. In the longitudinal direction, the biggest residual tensile stress appears on both sides of the welding seam line. When the laser welding power is 2.4 kW and welding speed is 20mm/s, the no apparent welding deformation’s 20CrMnSi gear can be achieved really.

Characteristics of Residual Stress in P92 Steel Welds

2007 ◽  
Vol 26-28 ◽  
pp. 1175-1180
Author(s):  
Keun Bong Yoo ◽  
Hyun Sun Choi ◽  
Eui Hyun Kim ◽  
Jae Hoon Kim
Keyword(s):  
Residual Stress ◽  
Compressive Residual Stress ◽  
Diffraction Method ◽  
Welding Residual Stress ◽  
Distribution Characteristics ◽  
X Ray Diffraction ◽  
P92 Steel ◽  
X Ray ◽  
Steel Welds ◽  
Directional Difference

Welding residual stress has important influence on the performance of engineering components. In this paper, the residual stress and FWHM were measured by X-ray diffraction method to investigate characteristics for P92 steel welds. The aim of the study is to estimate the residual stress and FWHM distribution characteristics. A compressive residual stress distributed as a function of depth has a different pattern in welds and base metal. A large tensile residual stress occurs welds and near the HAZ, but approaches gradually zero as away from the welding center. Residual stress and FWHM undergo rapid relaxation after PWHT. Also, FWHM is a scalar quantity without any directional difference and is proportional to hardness on the whole.

Studies of Half-Cell for Anode Supported SOFC after Reduction

2011 ◽  
Vol 287-290 ◽  
pp. 2511-2515 ◽  
Author(s):  
Xia Wang ◽  
Feng Hui Wang
Keyword(s):  
Residual Stress ◽  
Solid Oxide Fuel Cells ◽  
Hydrogen Reduction ◽  
Solid Oxide ◽  
X Ray Diffraction ◽  
Electrolyte Layer ◽  
Half Cell ◽  
X Ray ◽  
Stress Changes ◽  
Different Temperatures

The performance of half-cell for anode supported Solid Oxide Fuel Cells (SOFCs) is necessary to wide use of SOFCs. This work is to study the reduction degree of anode and the residual stress changes that occur during hydrogen reduction on the different temperatures and in different times. The porosity of the specimens with oxidation is less than that of the reduction one. There is no Ni phase in the sample before hydrogen reduction. After hydrogen reduction on 1000°C for 6 hours, there is no NiO phase in the sample. It reveals the NiO has been reduced into Ni completely. We also investigate residual stresses in the electrolyte layer using X-ray diffraction. The residual stress value of electrolyte is about -844.1MPa before reduction. After hydrogen reduction on 800°C for 9 hours, the residual stress is decreased to -474.8MPa. So the reduction temperature can choose as 600°C and the reduction time can choose as 9 hours.

Research on the Residual Stress of Aluminum Alloy (LF6) Welding

2013 ◽  
Vol 546 ◽  
pp. 127-131
Author(s):  
Zhi Qing Guo ◽  
Qiu Juan Lv ◽  
Yan Jiao Li ◽  
Chang Jiang Liu ◽  
Fang Xie
Keyword(s):  
Numerical Simulation ◽  
Residual Stress ◽  
Experimental Study ◽  
Aluminum Alloy ◽  
Stress Distribution ◽  
Residual Stress Distribution ◽  
Welding Residual Stress ◽  
Welding Seam ◽  
Maximum Value

This paper use the software ANSYS to study the aluminum alloy (LF6) welding residual stress by numerical simulation and experimental study. The result indicates that the aluminum alloy (LF6) has the same residual stress distribution with others, there is a maximum value existing at the range of 4-5mm near the welding seam.

Design and Application of MMM System for Welding Residual Stress Test

2012 ◽  
Vol 566 ◽  
pp. 534-537
Author(s):  
Hai Yan Xing ◽  
Ping Qin ◽  
Yan Min Lou
Keyword(s):  
Residual Stress ◽  
Stress Concentration ◽  
Stress Test ◽  
Object Oriented Programming ◽  
Welding Residual Stress ◽  
Testing System ◽  
Magnetic Memory ◽  
X Ray ◽  
Analysis And Evaluation ◽  
Examination Result

In order to apply metal magnetic memory (MMM) technology to welding residual stress testing, the MMM hardware and software system is designed. The software subsystem is based on object-oriented programming and the hardware subsystem is portable. The MMM system can test the welded joint residual stress distribution, residual stress concentration zones and defects at workshop. Moreover, the MMM testing system can output data to a computer not only for automatic evaluation but also for further analysis and evaluation with expert intervention. According to the trend of the MMM characteristic, the welding residual stress concentration and defects can be detected and evaluated. The field X-ray examination result is consistent with the result of the MMM testing system, which has proved the accuracy and engineering practicality of the MMM testing system.

The Calculation and Measurement of Welding Residual Stress for Invar Steel of a Liquefied Natural Gas Carrier’s Containment System

2015 ◽  
Vol 31 (01) ◽  
pp. 43-48
Author(s):  
DongSheng Zhao ◽  
Yulung Liu ◽  
XianDong Wang ◽  
ZhouShang Ji
Keyword(s):  
Residual Stress ◽  
Fatigue Life ◽  
Natural Gas ◽  
Diffraction Method ◽  
Liquefied Natural Gas ◽  
Welding Residual Stress ◽  
Welding Seam ◽  
Containment System ◽  
Longitudinal Residual Stress ◽  
Measurement Results

The finite element method is applied to calculate the welding residual stress for Invar steel of a liquefied natural gas (LNG) carrier's containment system, whereas the x-ray diffraction method is applied to measure the longitudinal welding residual stress of the welding joint. The calculation and measurement results indicate that the measurement results of longitudinal residual stress are lower than the calculation results, but the distribution of both results is consistent with each other. The measurement results indicate that the longitudinal residual stress near the welding seam increased first and then decreased with the increasing distance to the welding seam, and the tensile residual stress converted to the compressive stress gradually. There exists high longitudinal residual stress in the weld seam and the heat-affected zone of Invar steel, and the maximum residual stress is above 200MPa, which may decrease the fatigue life of Invar steel. Thus, the influence of welding residual stress cannot be neglected when you assess the fatigue life of a LNG carrier's containment system under the sloshing impact.

Analysis of Welding Residual Stress on Cracked Vessels with X-Ray Diffraction Method

2014 ◽  
Vol 937 ◽  
pp. 318-323
Author(s):  
Jun Ming Zhou ◽  
Yi Liang Zhang
Keyword(s):  
Residual Stress ◽  
Good Condition ◽  
Diffraction Method ◽  
Welding Residual Stress ◽  
High State ◽  
X Ray Diffraction ◽  
Light Hydrocarbons ◽  
X Ray ◽  
Heat Treated ◽  
The Impact

A large number of cracks are found in the 1500m3Liquefied Light hydrocarbons vessel during the inspection after two years of running.In totally,six vessels being fully heated treated is made of 15MnNbR. Researchers used X-ray stress analyzer measured the welding residual stress of vessels that have been cracked and uncracked. The results show that, residual stress of uncracked spherical vessels are in good condition, while those value of cracked is high, the value of the highest is 1.05σs. It indicates that the possible reason for the separation is the residual stress in the high state. Through welding and heat treated for the second time, the welding residual stress decreased obviously. It indicates the impact of this measure is good.

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