scholarly journals Welding-Metallurgical Evaluation for Residual Stress Measurement Accuracy of Multi-Pass Girth Welded Pipe Joint in Austenitic Stainless Steel by X-Ray Diffraction

2011 ◽  
Vol 60 (7) ◽  
pp. 610-616 ◽  
Author(s):  
Tadafumi HASHIMOTO ◽  
Shigetaka OKANO ◽  
Masahito MOCHIZUKI
Keyword(s):  
Residual Stress ◽  
Stainless Steel ◽  
Austenitic Stainless Steel ◽  
Measurement Accuracy ◽  
Stress Measurement ◽  
X Ray Diffraction ◽  
X Ray ◽  
Welded Pipe ◽  
Metallurgical Evaluation ◽  
Pipe Joint

X-Ray Diffraction Measurement of Residual Stresses in Thick, Multi-Pass Steel Weldments

1985 ◽  
Vol 107 (2) ◽  
pp. 185-191 ◽  
Author(s):  
C. O. Ruud ◽  
R. N. Pangborn ◽  
P. S. DiMascio ◽  
D. J. Snoha
Keyword(s):  
Residual Stress ◽  
Measurement Accuracy ◽  
Stress Measurement ◽  
Three Dimensional ◽  
Residual Stress Measurement ◽  
Stress Fields ◽  
Diffraction Measurement ◽  
X Ray Diffraction ◽  
X Ray ◽  
Removal Technique

A unique X-ray diffraction instrument for residual stress measurement has been developed that provides for speed, ease of measurement, accuracy, and economy of surface stress measurement. Application of this instrument with a material removal technique, e.g., electropolishing, has facilitated detailed, high resolution studies of three-dimensional stress fields. This paper describes the instrumentation and techniques applied to conduct the residual stress measurement and presents maps of the residual stress data obtained for the surfaces of a heavy 2 1/4 Cr 1 Mo steel plate weldment.

scholarly journals Residual Stress Tensor Distributions in Cracked Austenitic Stainless Steel Measured by Two-Dimensional X-Ray Diffraction Method

2014 ◽  
Vol 996 ◽  
pp. 128-134 ◽  
Author(s):  
Youichi Saito ◽  
Shunichiro Tanaka
Keyword(s):  
Residual Stress ◽  
Stainless Steel ◽  
Austenitic Stainless Steel ◽  
Stress Tensor ◽  
Equivalent Stress ◽  
Diffraction Method ◽  
Two Dimensional ◽  
X Ray Diffraction ◽  
Stress Concentrations ◽  
X Ray

The residual stress tensor for cracked austenitic stainless steel was measured by a two-dimensional X-ray diffraction method. Higher von Mises equivalent stress concentrations, attributed to hot crack initiation, were obtained at both crack ends. The stress of 400 MPa at the crack end in the columnar grain region was about two-fold larger than that of 180 MPa in the equiaxed grain region. This difference was caused by a depression in the cast slab.

Measuring residual stresses in stainless steel—recent experiences within a VAMAS exercise

2009 ◽  
Vol 24 (S1) ◽  
pp. S41-S44 ◽  
Author(s):  
A. T. Fry ◽  
J. D. Lord
Keyword(s):  
Residual Stress ◽  
Stainless Steel ◽  
Austenitic Stainless Steel ◽  
Residual Stresses ◽  
Best Practice ◽  
Test Procedure ◽  
Industrial Plant ◽  
X Ray Diffraction ◽  
X Ray ◽  
Industrial Sectors

Residual stresses impact on a wide variety of industrial sectors including the automotive, power generation, industrial plant, construction, aerospace, railway and transport industries, and a range of materials manufacturers and processing companies. The X-ray diffraction (XRD) technique is one of the most popular methods for measuring residual stress (Kandil et al., 2001) used routinely in quality control and materials characterization for validating models and design. The VAMAS TWA20 Project 3 activity on the “Measurement of Residual Stresses by X-ray Diffraction” was initiated by NPL in 2005 to examine various aspects of the XRD test procedure in support of work aimed at developing an international standard in this area. The purpose of this project was to examine and reduce some of the sources of scatter and uncertainty in the measurement of residual stress by X-ray diffraction on metallic materials, through an international intercomparison and validation exercise. One of the major issues the intercomparison highlighted was the problem associated with measuring residual stresses in austenitic stainless steel. The following paper describes this intercomparison, reviews the results of the exercise and details additional work looking at developing best practice for measuring residual stresses in austenitic stainless steel, for which X-ray measurements are somewhat unreliable and problematic.

Effect of Hydrogen on the Micro- and Macro-Strain near the Surface of Austenitic Stainless Steel

2014 ◽  
Vol 936 ◽  
pp. 1298-1302 ◽  
Author(s):  
Osamu Takakuwa ◽  
Yuta Mano ◽  
Hitoshi Soyama
Keyword(s):  
Residual Stress ◽  
Stainless Steel ◽  
Austenitic Stainless Steel ◽  
Compressive Stress ◽  
Parameter Method ◽  
Fundamental Parameter ◽  
X Ray Diffraction ◽  
Diffraction Profile ◽  
X Ray ◽  
Hydrogen Charging

The objective of this study is to evaluate the effect of hydrogen on the micro-and macro-strain of austenitic stainless steel using X-ray diffraction. When hydrogen is trapped in lattice sites, it can affect both the micro-and macro-strain. The micro-strain was evaluated through fitting profiles to measured X-ray diffraction profile using a fundamental parameter method. The macro-strain, i.e., the residual stress, was evaluated by a 2D method using a two-dimensional PSPC. The experimental samples were charged with hydrogen by a cathodic charging method. The results revealed that the induced residual stress was equi-biaxial and compressive, and that the micro-strain increased. Both of these varied rapidly with increasing hydrogen charging time. Saturation occurred at a compressive stress of around 130 MPa. On reaching saturation, the hydrogen charging was terminated and desorption of hydrogen began at room temperature. Then, the strains decreased and the compressive stress reverted, ultimately, to a tensile stress of 180 MPa. Martensitic transformation occurred due to hydrogen charging and this had a significant effect on the X-ray diffraction profile.

Residual Stress by X-Ray Diffraction and Microstructure for Multi-Pass Girth Welded Pipe Joint in Austenitic Stainless Steel Type 316L

2011 ◽  
Author(s):  
Tadafumi Hashimoto ◽  
Shigetaka Okano ◽  
Shinro Hirano ◽  
Masahito Mochizuki ◽  
Kazutoshi Nishimoto
Keyword(s):  
Residual Stress ◽  
Stainless Steel ◽  
Austenitic Stainless Steel ◽  
Diffraction Method ◽  
Incident Beam ◽  
Austenitic Stainless Steels ◽  
Secondary Phase ◽  
Primary Phase ◽  
X Ray Diffraction ◽  
X Ray

Residual stress due to welding can result in brittle fracture, fatigue failure, and stress corrosion cracking in welded structures. Measuring residual stresses are of great importance, if crack propagation needs to be evaluated. However, it is especially known that the X-ray diffraction method makes remarkable different for austenitic stainless steel, because the microstructures in welds change from the original microstructures during welding thermal cycle. That is, there are the preferred orientation due to the unidirectional solidification and the grain growth in the heat-affected zone. In order to average the sin2Ψ plots to exclude them, Ψ oscillation of ±3 deg was performed and the incident beam size was broadened to 4 by 4 mm. Consequently, typical residual stress distributions due to welding were obtained to various conditions. The residual stress distribution measured by X-ray diffraction agrees very well with that the estimated by thermal-elastic-plastic analysis, if the spatial resolution is correlated. It is attributed that the δ-ferrite grows as the primary phase and the austenite precipitates or crystallizes as the secondary phase. When the secondary austenite nucleates with the Kurdjiumov-Sachs relationship which satisfy δ{110}//γ{111} and δ<111>//γ<110>, plate-like austenite grows randomly into the ferrite and austenite grains are braked up. That is, Specific systems in austenitic stainless steels should be classified, as a material that residual stress can be measured accurately by X-ray diffraction.

scholarly journals Optimization of Residual Stress Measurement Conditions for a 2D Method Using X-ray Diffraction and Its Application for Stainless Steel Treated by Laser Cavitation Peening

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2772
Author(s):  
Hitoshi Soyama ◽  
Chieko Kuji ◽  
Tsunemoto Kuriyagawa ◽  
Christopher R. Chighizola ◽  
Michael R. Hill
Keyword(s):  
Residual Stress ◽  
Stainless Steel ◽  
Evaluation Method ◽  
Stress Measurement ◽  
X Ray Diffraction ◽  
Stress Variation ◽  
X Ray ◽  
Slitting Method ◽  
Average Grain Size ◽  
Measured Residual Stress

As the fatigue strength of metallic components may be affected by residual stress variation at small length scales, an evaluation method for studying residual stress at sub-mm scale is needed. The sin2ψ method using X-ray diffraction (XRD) is a common method to measure residual stress. However, this method has a lower limit on length scale. In the present study, a method using at a 2D XRD detector with ω-oscillation is proposed, and the measured residual stress obtained by the 2D method is compared to results obtained from the sin2ψ method and the slitting method. The results show that the 2D method can evaluate residual stress in areas with a diameter of 0.2 mm or less in a stainless steel with average grain size of 7 μm. The 2D method was further applied to assess residual stress in the stainless steel after treatment by laser cavitation peening (LCP). The diameter of the laser spot used for LCP was about 0.5 mm, and the stainless steel was treated with evenly spaced laser spots at 4 pulses/mm2. The 2D method revealed fluctuations of LCP-induced residual stress at sub-mm scale that are consistent with fluctuations in the height of the peened surface.

scholarly journals Non-destructive Micro-structural Characterization of Metallic Specimens with a Portable X-ray Diffraction based Residual Stress Analyzer

2015 ◽  
Vol 2 (1) ◽  
pp. 22 ◽  
Author(s):  
P. Ganesh ◽  
D. C. Nagpure ◽  
Rakesh Kaul ◽  
R. K. Gupta ◽  
L. M. Kukreja
Keyword(s):  
Residual Stress ◽  
Stainless Steel ◽  
Austenitic Stainless Steel ◽  
Crystallographic Texture ◽  
Diffraction Peak ◽  
Surface Microstructure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Non Destructive

Non-destructive characterization of surface microstructure of an engineering component is an important parameter to assess its fitness to function in the given service conditions. The paper describes various case studies performed in authors’ laboratory involving use of portable X-ray diffraction based residual stress analysis system to examine and understand the micro-structural state of the investigated surface. A significant decrease in full width at half maximum (FWHM) of gamma(311) diffraction peak from about 4.2° in the cold worked state to about 2.5° in the annealed/surface melted state was recorded for austenitic stainless steel. In case of 0.4% carbon steel there is sharp increase in FWHM of alpha(211) diffraction peak from about 2° in the as received condition to about 5-6° in the laser hardened condition. Crystallographic texture developed during electro-plating of chromium on stainless steel, could be detected from the strong intensity of alpha (211) peak of chromium at about 19° to the surface normal with respect to all other X-ray inclination angles (ѱ) during residual stress measurement. The results show that FWHM and intensity variation of the diffraction peak are two sensitive parameters for characterization of surface microstructure. Change in FWHM has been used to detect machining-induced cold deformation and evolution of re-crystallized grains in austenitic stainless steel and formation of hard martensite in laser transformation hardened ferritic steel. Variation in the intensity of diffracted peak with respect to X-ray inclination angle provided valuable information regarding crystallographic texture in hard chrome plated deposits.

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