Experimental/Modelling Study of Residual Stress in Al/SiCp Bent Bars by Synchrotron XRD and Slitting Eigenstrain Methods

2008 ◽  
Vol 571-572 ◽  
pp. 277-282 ◽  
Author(s):  
Xu Song ◽  
Solène Chardonnet ◽  
Giancarlo Savini ◽  
Shu Yan Zhang ◽  
Willem J.J. Vorster ◽  
...  
Keyword(s):  
Residual Stress ◽  
Residual Stresses ◽  
Residual Strain ◽  
Numerical Models ◽  
Front Face ◽  
Stress Profile ◽  
X Ray Diffraction ◽  
Element Analysis ◽  
X Ray ◽  
Residual Stress Profile

The aim of the study presented here was to evaluate the residual stresses present in a bar of aluminium alloy 2124-T1 matrix composite (MMC) reinforced with 25vol% particulate silicon carbide (SiCp) using X-ray diffraction and 3D profilometry (curvature measurement using Mitutoyo/Renishaw coordinate measurement machine) and comparing these results with numerical models of residual strain and stress profiles obtained by a simple inelastic bending model and Finite Element Analysis (FEA). The residual strain distribution was introduced into the test piece by plastic deformation in the 4-point bending configuration. At the first stage of this study the elasticplastic behaviour of the MMC was characterized under static and cyclic loading to obtain the material parameters, hardening proprieties and cyclic hysteresis loops. Subsequently, synchrotron Xray diffraction and CMM curvature measurements were performed to deduce the residual stress profile in the central section of the bar. The experimental data obtained from these measurements were used in the inelastic bending and FEA simulations. The specimens were then subjected to incremental slitting using EDM (electric discharge machining) with continuous back and front face strain gauge monitoring. The X-ray diffraction and incremental slitting results were then analysed using direct and inverse eigenstrain methods. Residual stresses plots obtained by different methods show good agreement with each other.

Residual Stress Depth-Profiling in Shot-Peened Al Alloy Components Subjected to Fatigue Testing

2010 ◽  
Vol 638-642 ◽  
pp. 2464-2469 ◽  
Author(s):  
Cristy Leonor Azanza Ricardo ◽  
G. Degan ◽  
M. Bandini ◽  
Paolo Scardi
Keyword(s):  
Residual Stress ◽  
Fatigue Testing ◽  
Depth Profiling ◽  
Cyclic Stress ◽  
Al Alloy ◽  
Stress Profile ◽  
X Ray Diffraction ◽  
X Ray ◽  
Residual Stress Profile ◽  
Number Of Cycles

The residual stress profile in a shot-peened Al alloy component was studied by a recently proposed method based on the known procedure of progressive thinning and X-ray Diffraction measurements. The effect the cyclic stress on the fatigue life was studied in detail, showing the correlation between nominal load and residual stress relaxation. Besides showing the expected decrease of compressive stress with the load and number of cycles, the present work highlights the importance of changes in the through-the-thickness residual stress distribution.

Experimental Comparison of In-Depth Residual Stresses Measured with Neutron and X-Ray Diffraction with a Numerical Stress Relaxation Correction Method

2017 ◽  
Vol 905 ◽  
pp. 131-136
Author(s):  
Bruno Levieil ◽  
Florent Bridier ◽  
Cédric Doudard ◽  
Vincent Klosek ◽  
David Thévenet ◽  
...  
Keyword(s):  
Residual Stress ◽  
Stress Relaxation ◽  
Neutron Diffraction ◽  
Residual Stresses ◽  
Correction Method ◽  
Experimental Comparison ◽  
X Ray Diffraction ◽  
Element Analysis ◽  
Notched Specimen ◽  
X Ray

This study is an experimental comparison of in-depth X-ray diffraction residual stress measurements with neutron diffraction measurements. The goal is to evaluate the relevance of the Savaria-Bridier-Bocher [1] stress relaxation correction method. Neutron diffraction are performed on a bent notched specimen. Destructive X-ray diffraction is performed until 5.25mm below the surface by polishing the material. This polishing induces stress relaxation and X-ray diffraction results have to be corrected. For that purpose, a finite element analysis is realised and show good correlation with neutron measurements results. The application of the stress correction method improves the X-ray measurements especially after 2 mm below the surface. The differences between measured and corrected residual stresses from both diffraction techniques are analyzed and discussed.

Residual Stresses around an Expanded Hole in an Aluminum Clad Sheet

2005 ◽  
Vol 490-491 ◽  
pp. 41-46 ◽  
Author(s):  
P. Matos ◽  
Pedro Miguel Guimarães Pires Moreira ◽  
J.C.P. Pina ◽  
A. Morão Dias ◽  
Paulo Manuel Salgado Tavares de Castro
Keyword(s):  
Residual Stress ◽  
Fatigue Cracks ◽  
Numerical Data ◽  
Stress Profile ◽  
Detailed Knowledge ◽  
X Ray Diffraction ◽  
Element Analysis ◽  
Residual Stress Profile ◽  
Clad Sheet ◽  
Numerical Tools

Cold working introduces a compressive stress field around rivet holes, reducing the tendency for fatigue cracks to initiate and grow under cyclic mechanical loading. As it is well known, for the accurate assessment of fatigue lifetimes a detailed knowledge of the residual stress profile is required. Powerful experimental and numerical tools are nowadays available for that purpose. In the present work both types of tools, X-ray diffraction and 3D Finite Element Analysis (FEA), were used in order to evaluate the residual stress profile. A comparison of experimental and numerical data is presented and discussed.

scholarly journals Investigations on Residual Stresses within Hot-Bulk-Formed Components Using Process Simulation and the Contour Method

Metals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 566
Author(s):  
Bernd-Arno Behrens ◽  
Jens Gibmeier ◽  
Kai Brunotte ◽  
Hendrik Wester ◽  
Nicola Simon ◽  
...  
Keyword(s):  
Residual Stress ◽  
Residual Stresses ◽  
Process Simulation ◽  
Hot Forming ◽  
Contour Method ◽  
Stress Profile ◽  
X Ray Diffraction ◽  
Forming Process ◽  
Near Surface ◽  
X Ray

Residual stresses resulting from hot-forming processes represent an important aspect of a component’s performance and service life. Considering the whole process chain of hot forming, the integrated heat treatment provided by a defined temperature profile during cooling offers a great potential for the targeted adjustment of the desired residual stress state. Finite element (FE) simulation is a powerful tool for virtual process design aimed at generating a beneficial residual stress profile. The validation of these FE models is typically carried out on the basis of individual surface points, as these are accessible through methods like X-ray diffraction, hole-drilling, or the nanoindentation method. However, especially in bulk forming components, it is important to evaluate the quality of the model based on residual stress data from the volume. For these reasons, in this paper, an FE model which was already validated by near surface X-ray diffraction analyses was used to explain the development of residual stresses in a reference hot forming process for different cooling scenarios. Subsequently, the reference process scenarios were experimentally performed, and the resulting residual stress distributions in the cross-section of the bulk specimens were determined by means of the contour method. These data were used to further validate the numerical simulation of the hot forming process, wherein a good agreement between the contour method and process simulation was observed.

scholarly journals Effect of a Multiple Reduction Die on the Residual Stress of Drawn Materials

Materials ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1358
Author(s):  
Jeong-Hun Kim ◽  
Chang-Hyun Baek ◽  
Sang-Kon Lee ◽  
Jong-Hun Kang ◽  
Joon-Hong Park ◽  
...  
Keyword(s):  
Neural Network ◽  
Residual Stress ◽  
Finite Element Analysis ◽  
Finite Element ◽  
Residual Stresses ◽  
Deep Neural Network ◽  
Drawing Process ◽  
X Ray Diffraction ◽  
Element Analysis ◽  
X Ray

Residual stress may influence the mechanical behavior and durability of drawn materials. Thus, this study develops a multiple reduction die (MRD) that can reduce residual stress during the drawing process. The MRD set consists of several die tips, die cases, and lubricating equipment. All the die tips of the MRD were disposed of simultaneously. Finite element analysis of the drawing process was performed according to the reduction ratio of each die tip, and the variables in drawing process with the MRD were optimized using a deep neural network to minimize the residual stress. Experiments on the drawing process with the conventional die and MRD were performed to evaluate the residual stress and verify the effectiveness of the MRD. The results of X-ray diffraction measurements indicated that the axial and hoop residual stresses on the surface were dramatically reduced.

Application of the Eigenstrain Theory to Predict Residual Stress around Curved Edges after Laser Shock Peening

2013 ◽  
Vol 768-769 ◽  
pp. 185-192 ◽  
Author(s):  
Stefano Coratella ◽  
M. Burak Toparli ◽  
Michael E. Fitzpatrick
Keyword(s):  
Residual Stress ◽  
Residual Stresses ◽  
Laser Shock Peening ◽  
Stress Profile ◽  
Laser Shock ◽  
Element Analysis ◽  
Residual Stress Profile ◽  
The Finite Element Analysis ◽  
Treatment Technologies ◽  
Shock Peening

Residual stresses play a fundamental role in mechanical engineering. They can be generated by manufacturing processes or introduced purposely by surface treatment technologies. One of the most recent technologies developed to introduce residual stresses is Laser Shock Peening. Since it is a relatively expensive technology, a fundamental role is played by the Finite Element Analysis approach to predict the final residual stress profile. The FEA approach consists of either direct simulation of the LSP process or the application of the eigenstrain approach. The application of the eigenstrain theory in predicting residual stresses after LSP treatment in curved edges is the subject of this research.

X-ray diffraction grazing-incidence methods applied for gradient-free residual stress profile measurements in electrodeposited Ni coatings

2015 ◽  
Vol 48 (1) ◽  
pp. 71-78 ◽  
Author(s):  
Bogusz Kania ◽  
Paulina Indyka ◽  
Leszek Tarkowski ◽  
Ewa Beltowska-Lehman
Keyword(s):  
Residual Stress ◽  
Incidence Angle ◽  
Grazing Incidence ◽  
Stress Profile ◽  
Angle Of Incidence ◽  
X Ray Diffraction ◽  
X Ray ◽  
Residual Stress Profile ◽  
Constant Angle ◽  
Graded Material

The present work investigates the possibility of bias introduced in grazing-incidence-angle X-ray diffraction techniques applied to residual stress measurements. In these studies, monotextured nanocrystalline nickel coatings obtained by electrodeposition were examined as the model reference samples. Selected Ni coatings exhibited well developed and simple gradient-free residual stress states that were visible using conventional sin2ψ measurements with varying X-ray penetration depths. These results were verified against the stress state picture obtained by two variants of grazing-incidence X-ray methods: multi-reflection (differenthkl) and constant angle of incidence (singlehkl). The outcome of both grazing techniques consistently excluded stress gradients in the samples, which agreed with conventional sin2ψ measurement results. However, only the results of the constant angle of incidence technique agreed with those obtained by the sin2ψ method in terms of calculated residual stress level, suggesting this approach could be applied in further studies of graded material coatings. All analysed coatings yielded uniformly distributed tensile residual stress related to gradual structure development in electrodeposited Ni coatings studied by electron microscopy techniques.

scholarly journals Influence of Tempering Conditions on Shot-Peened Tool Steel Components In-Depth Residual Stress Profiles

2014 ◽  
Vol 996 ◽  
pp. 769-774
Author(s):  
Diego Cecchin ◽  
Evgeny Kobza ◽  
Marco Cazzolli ◽  
Cristy Leonor Azanza Ricardo ◽  
Mirco D'Incau ◽  
...  
Keyword(s):  
Residual Stress ◽  
Dislocation Density ◽  
Tool Steel ◽  
Stress Profile ◽  
X Ray Diffraction ◽  
Density Profiles ◽  
X Ray ◽  
Residual Stress Profile ◽  
Stress Profiles ◽  
Pattern Modeling

Tool steel (X155CrVMo121KU in the following UK15) samples were analyzed to determine the in-depth residual stress profile and to study modifications in the microstructure, induced by a shot-peening treatment. The influence of different tempering temperatures was studied. Residual stress and dislocation density profiles were measured using standard laboratory X-ray diffraction (XRD) residual stress analysis with progressive chemical layer removal. Dislocation density profiles where obtained using a Whole Powder Pattern Modeling (WPPM) procedure.

Residual Stresses in Ultrathin Metal Sublayers Within Au/Ni Multilayers

1997 ◽  
Vol 475 ◽  
Author(s):  
S. Labat ◽  
P. Gergaud ◽  
O. Thomas ◽  
B. Gilles ◽  
A. Marty ◽  
...  
Keyword(s):  
Residual Stress ◽  
Residual Stresses ◽  
Residual Strain ◽  
Strain State ◽  
Lattice Parameter ◽  
Metallic Multilayers ◽  
X Ray Diffraction ◽  
X Ray ◽  
Residual Strains ◽  
Far From Equilibrium

ABSTRACTMetallic Multilayers (MLs) have attracted a considerable interest during these last years because of their unusual properties. In small periods ML's (a few nm) the high density of interfaces give rise to structures very far from equilibrium. Au/Ni multilayers have been grown in the (111) orientation by M.B.E. on Si(100) via a Cu(100) buffer layer. Two different parameters have been studied: the Au:Ni ratio at constant (4 nm) superperiod and the superperiod at constant (1:1) Au:Ni ratio. The full strain state of Au and of Ni has been determined via x-ray diffraction measurements. The high lattice parameter misfit beween Au and Ni (14%) implies that all the layers are partially relaxed. Residual strains as high as several % are encountered. The residual strain in the Au layers is clearly correlated with their thickness. A residual stress as high as 3.9 GPa is determined in the thinner layers.

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