bluuebunny/crossref_metadata_2025 huggingface dataset:
Industrial Injuries Appraisal in Mines of JSC “SUEK Kuzbass”
Authors: Kovshov Stanislav , Istomin Ruslan , Nikulin Andrei , Sotiriu Alexandra
Published: August 2014

In this article the existing appraisal system of industrial injuries applied in mines of JSC “SUEK Kuzbass” is considered. Its merits and demerits are analyzed. As addition to applied system it is offered to use a topographical industrial injuries analysing method. Its application allows to investigate more deeply the reasons of industrial injuries and to undertake measures for its minimization. This article includes the estimation risk method of industrial injuries in mines which based on the statistics of industrial accidents and allows managing more efficiency of financing to labour. Technical approach for industrial accidents analysis in mines is represented. More over it contains information about geological and technical conditions the place of industrial accident. It has been proved the possibility to forecast industrial accident in mines by each factor which based on score method of the risk estimation For the first time realized classification of mines on the group where the main measure is the result of using the new method. The result of the study introduced on the industrial safety executive system of JSC “SUEK Kuzbass” (Russia).
Innovative Safety System of Work of Wood Cutting Electric Table Saw, Based on the Measurement of Current Consumption
Authors: Rybakowski Marek , Bachman Paweł
Published: August 2014

The main objective of the study was to develop an innovative safety system of wood cutting electric table saws, based on measurements of power consumption. Practical use of the proposed technical solution is a prolonged lifetime of the cutter and its blade, reduction of the risk of overheating due to friction of treated wood - which can lead to ignition of wood and wood dust, and therefore reduce the risk of occurrence of the accident, a fire or an injury. Further research directions were indicated.
Risk Assessment Method Applied for Waste Ashes Processing and Further Use as a Renewable Source
Authors: Malindžáková Marcela , Rosová Andrea
Published: August 2014

The aim of this article is to describe the optimization of ashes processing technological line. The statistical and economic tool (risk assessment criteria) that is used in this article help to identify weaknesses in the ashes processing, managing process and potential risks and bottlenecks, thus helping to achieve better control over the process, minimizing the impact on the environment.
Keywords: Ash processing, Waste storage, Risk assessment.
Working Effectiveness of Hydraulic Rescue Equipments for Firefighters
Authors: Marcinek Milan , Marková Iveta
Published: August 2014

Author deals with the topic relating to use of hydraulic extrication tools at technical interventions in the field of person extrication and closer characterizes individual technical items. He characterizes material and technical equipage of responding units and emphasizes a need of systematic solving of each extraordinary emergency situation relating to persons extrication.
The aim of paper is research of safe use of a method of DVT when cutting column B within the intervention of a traffic accident on the selected car.
For the purpose of research are realized of comparison of times required for opening and closing of selected types of hydraulic. There are use hydraulic shears Holmatro ® CU 3040 NCTM, hydraulic shears Holmatro ® CU 4035 C, hydraulic shears Weber Hydraulik S-260.
Hazard Analysis in Phenol Removal from Natural Water Sources
Authors: Galbičková Blanka , Belcik Michal , Hrušovský Ivan , Soldán Maroš , Balog Karol , Ševčíková Janka
Published: August 2014

AOP processes (Advanced Oxidation processes) are presently used as an alternative to traditional methods for removing of persistent pollutants from wastewater. Article is focused on removal of phenol from wastewater by using UV photodegradation. As a source of UV light medium pressure mercury lamp with output 400W is used. The aim of article is to perform hazard analysis in work with UV photoreactor by HAZOP method, eliminate risks in working with this equipment and propose corrective measures to improve quality of health and safety during work.
Monitoring the Acid Neutralisation Capacity and Options for Leaching Iron from Waste Mud from the Production of Al2O3
Authors: Hroncová Emília , Ladomerský Juraj , Ďuricová Anna , Puskajler Jozef
Published: August 2014

Red and brown mud is created in the processing of bauxite into Al2O3. The chemical composition of red and brown mud depends upon the method of processing bauxite on a mud landfill, and the time and availability of mud leaching by rain. Samples of red mud from landfill in Žiarska Kotlina had pH values of 9.46 ± 0.11 and brown mud had 10.2 ± 0.15. We studied the development of changes in pH and concentrations of Fe (spectrometrically with AAS) in eluates during the leaching of red and brown mud samples. Results show that there is no release of Fe during brown mud elution. When using 0.025 and 0.05 M H2SO4 for elution, the pH decreased slightly from 10.2 ± 0.15 to 2.4 ± 0.05. Elution of 0.1 M H2SO4 shows that pH decreased to a value of 2.2 ± 0.05 by the 40th fraction and then it fell to a value of 1.77 ± 0.04 in the 100th fraction. The greatest amount of iron was released in the 8th and 55th fraction at a pH of 2 – 4 which could be observed by the change in colour of eluates. The progress of the release of iron was similar for both kinds of mud. Then we determined the neutralisation capacities of various fractions of mud in H2SO4, NaOH and H2O leachates by titration. It was discovered that the reaction of the alkaline proportions of red mud with the agent is greatest with fine granularity but for red mud, it does not change depending upon the size of the grain. The release of acid proportions depended upon time not upon texture. When leaching with water, the leached alkaline compounds from brown mud are mainly from the finest particles, and in the case of red mud, it was the opposite, from the largest particle fraction.
A Review on the Synthesis and Controlled Release Properties of Novel Responsive Carrier
Authors: Zhu Xiao Min , Zhao Ting Ting , Huang Ran
Published: August 2014

Interest in the stimuli-responsive polymers has been going on for decades, and a lot of work has been dedicated to the development of environmentally sensitive macromolecules that can be crafted into novel responsive carrier materials. This article reviews the state-of-the art in smart responsive carriers for controlled drug delivery applications. And the preparation methods of different responsive materials, sustained and controlled release performance are summarized. The significance and future of smart responsive materials are also commented.
Effect of the Nano-SiO2 Particles in Gelatin and Chitosan Based Wound Dressing Materials on the Antimicrobial Effects
Authors: Wang Li Bo , Liu Xiao Yang , Wei Jun , Jiang Hong
Published: August 2014

Wound dressing materials were obtained from gelatin, chitosan and nanoSiO2particles as filler. The barrier property to water vapor, water uptake ratio and antimicrobial properties of the wound dressing materials were investigated. The addition of the nanoSiO2particles endowed the materials good water uptake ratio and the barrier property to water vapor, whereas the antimicrobial agents improve the barrier property producing more hydrogen bonds. Moreover, the networks of the wound dressing materials with nanoSiO2particles displayed excellent compound binding capacity could reduce the permeation of water and increase the antimicrobial effect of the materials. The antimicrobial agents endowed the wound dressing materials with antimicrobial effect.
Dielectric Behavior of PVDF/PP-PT Nanocomposite Thin Films
Authors: Yu Ting Ting , Ren Zhao Hui , Yin Si Min , Yang Xin , Yu Yi Feng , Li Xiang , Wei Xiao , Xu Gang , Shen Ge , Han Gao Rong
Published: August 2014

PVA/PVP-assisted hydrothermal method was used to prepare single-crystal pre-perovskite PbTiO3(PP-PT) nanofibers, in which polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP) acted as surfactants. Subsequently, poly (vinylidene fluoride)/ pre-perovskite PbTiO3nanofibers (PVDF/PP-PT) nanocomposite thin films were successfully fabricated by a spin-coating method. The test results showed that PP-PT nanofibers had a good distribution in PVDF matrix. Moreover, α-phase coexisted with β-phase in the PVDF and PVDF/PP-PT nanocomposite thin films. The dielectric properties of the PVDF/PP-PT nanocomposite thin films were measured as a function of frequency in the range of 5 kHz to 5 MHz. It is worth noting that the dielectric constant of nanocomposite thin films increased with increasing the weight ratio of PP-PT nanofibers in the low frequency range. By contrast, the dielectric constant of PVDF/PP-PT nanocomposite thin film which contained 20% PP-PT nanofibers was 43.7% larger than that of pure PVDF thin film (εr= 6.77) at 5 kHz, and the loss tangent was ~0.03.
Synthesis and Applications of Gold Nanoparticles
Authors: Zhao Ting Ting , Lu Jing Juan , Tan Lian Jiang
Published: August 2014

This paper gives an introduction to the synthetic methods of gold nanoparticles, such as reduction method, template method and seed growth method. The reduction technique includes green reduction, template reduction and organic small molecules method. In addition, the applications of gold nanoparticles in nanoprobes, drug delivery systems, photonic crystals, etc. are discussed, and an outlook for the gold nanoparticles is also made.
Casting Transformers APG Manufacturing Technology
Authors: Chen Xiao Li , Shi Hong Wei , Song Xiao Guang , Wang Hong Chao , Gong Hao
Published: August 2014

The APG (Automatic Pressure Gelation) process of epoxy resin casting transformer had been studied in this paper, which was developed toward epoxy resin vacuum casting process. The raw materials, mold, the differences with vacuum casting process,casting process with its parameters were introduced. Also the factors that influences the partial discharge experiment of transformer were analyzed,especially the body making and casting processes.
New Modelling Approach for Micromechanical Modelling of the Elastoplastic Behaviour
Authors: Fajoui Jamal , Gloaguen David , Alimi Amel , Kchaou Mohamed , Jacquemin Frédéric , Elleuch Riadh
Published: August 2014

A new theoretical approach is developed to simulate the elastoplastic behaviour in cubic alloys during various strain-path changes. The polycristal is considered as a composite consisting of hard dislocation walls of high local dislocation density which are separated by soft regions of low local dislocation density. The improved elasto-plastic self-consistent method is applied to deduce the global behaviour of the aggregate. The model is tested by simulating the macroscopic behavior and the development of intergranular strains during different complex loads.
Distribution of Residual Deformation Effects in Shell Tubes from Ferritic-Martensitic Steels
Authors: Perlovich Yuriy , Isaenkova Margarita , Zharikov Evgeniy , Krymskaya Olga
Published: August 2014

The X-ray method of Generalized Pole Figures was used by study of residual deformation effects in steel shell tubes for high-temperature atomic reactor. Ferritic-martensitic steel contained disperse strengthening oxide particles and their behavior under technological treatment was of essential practical interest. The used procedure estimates residual deformation effects in grains with different orientations and depicts distributions of elastic lattice distortion and interplanar spacings. Invisible oxide particles redistribute within the tube wall and strain hardening at its outer side is higher.
Energy-Dispersive Residual Stress Analysis under Laboratory Conditions: Concept for a New Type of Diffractometer
Authors: Liehr Alexander , Klaus Manuela , Zinn Wolfgang , Genzel C. , Scholtes Berthold
Published: August 2014

In the past decade energy-dispersive (ED) synchrotron diffraction has evolved into a powerful tool for materials analysis. Recording complete diffraction patterns in rather few different measuring directions allows for depth-resolved analysis not only of the near-surface residual stress state, but also of composition and even texture gradients. However, since the number of synchrotron beamlines dedicated to ED-diffraction is restricted to very few instruments, alternatives have to be found which allow for ED residual stress analysis even under low flux laboratory conditions. In this project we start to establish the scientific basis for a measuring and evaluation method to make the transfer of the ED method to the laboratory dimensions possible, which is adapted to the conditions of much lower photon flux and larger beam divergences of laboratory X-ray sources. In this paper, we present the concept of an ED-diffractometer which is equipped with two detectors to enable simultaneous data acquisition for two orientations of the diffraction vector with respect to the sample reference system. The first constructive and experimental steps are presented and furthermore the possibilities and limitations of the new laboratory method and the advantages of the ED diffraction method to realize short measurement times in order to realize a high resolution of information depth are discussed.
Optimizing Experiment Performance by Realistic Sample Simulations
Authors: Boin Mirko , Wimpory Robert Charles , Woracek Robin
Published: August 2014

A simulation of realistic samples within a neutron scattering or imaging experiment has been created in order to support the accuracy, feasibility and analysis of residual stress measurements as well as the development of novel experimental methods and instrument components. Covering the influences of individual neutron instrument parameters, the simulation also assists in optimizing the experimental configuration towards precise measurements and effective usage of neutron beamtime.
Gamma Profile Analysis for Stress, Texture and Grain Size
Authors: He Bob B.
Published: August 2014

Two-dimensional X-ray diffraction pattern can be described by the diffraction intensity distribution in both 2θ and γ directions. The 2D pattern can be reduced to two kinds of profiles: 2θ-profile and γ-profile. The 2θ-profile can be evaluated for phase identification, crystal structure refinement and many applications with many existing algorithms and software. The γ-profile contains information on texture, stress, and crystal grain size. This article introduces the concept and fundamental algorithms for stress, texture and crystal size analysis by γ-profile analysis.
External Reference Samples for Residual Stress Analysis by X-Ray Diffraction
Authors: Lefebvre Fabien , Wasniewski E. , François Manuel , Cacot J. , Le-Bec P. , Baumhauer E. , Bouscaud D. , Bergey T. , Blaize D. , Gloaguen D. , Cosson A. , Jegou S. , Cheynet Y. , Leray S. , Meheux M. , Monvoisin J.C. , Allain P. , Vidal J.C. , Sprauel J.M. , Goudeau P. , Charles C. , Daflon L. , Fischer C. , Desmas L. , Ouakka A. , Moya M.J. , Bordiec Y. , Hamdi H.
Published: August 2014

The GFAC (French Association for residual stress analysis) has been working for several years on external reference samples in relation with the EN 15305-2009 standard. The purpose of this campaign is to provide an external reference sample to each laboratory involved in the round-robin to allow a good calibration, a good quality control of their X-ray diffraction system and an easiest way to compare results between laboratories. All the procedures to qualify external reference materials will be described in the paper.
X-Ray Optics and Precision Requirements for Residual Stress Analyses with High Spatial Resolution
Authors: Eigenmann Bernd
Published: August 2014

In recent years, the demand for high spatial resolution in X-ray residual stress analysis has drastically increased. The locations of interest are frequently small foot radii of teeth of gears. Also the inner surface of holes or hollow cylinders in general with small diameter must be investigated after opening the cylindrical cavities. In resolving such measuring problems, significant progress has been made in reproducibly manufacturing and applying glass capillary X-ray optics. With focusing elliptical polycapillaries and conventional laboratory X-ray sources, spot sizes of few 10 μm can be realized at sufficiently intensities for residual stress analyses. However, glass capillary optics require refined alignment strategies which are completely different from those for conventional beam shaping optics. Moreover, the small spot sizes cannot be aligned and positioned on the sample surface by eye. Microscopy fixtures are required. Finally, measurements in small radii result in high precision requirements for the diffractometers as well as for the sample positioning in axes and directions which are significantly less relevant when measuring on plane surfaces. The specific requirements resulting from residual stress analyses with high spatial resolution using glass capillaries and small spot sizes at curved surfaces are described and discussed.
Beyond the Streetlight Effect: A United Future for Relaxation and Diffraction Methods for Residual Stress Measurement
Authors: Prime Michael B. , Steinzig Michael L.
Published: August 2014

Residual stress measurement techniques can be categorized as either relaxation or diffraction methods. Practitioners often advocate a particular category and sometimes a specific technique (hole drilling, contour, XRD, neutron, etc) based on their experience or capability rather than using the best technique for the particular application. This paper considers some of the implications from applying this “drunkard’s search” or “streetlight” approach by examining examples where the critical stress could be hidden from both relaxation and diffraction measurements. A better approach to planning residual stress measurements would begin with a detailed consideration of why the stresses should be measured and how the results will be used. Only then can the most appropriate measurement plan be developed. Since a single measurement technique cannot reveal the full state of stress, especially in challenging parts, the use of multiple measurement types often provides the most useful information to customers.
Numerical Reconstruction of Residual Stress Fields from Limited Measurements
Authors: Coules Harry E. , Smith David J. , Serasli Karim H.A.
Published: August 2014

By finding stress states which are consistent both with any existing experimental measurements and with elasticity theory, residual stress fields can often be reconstructed from incomplete measurement data. We discuss such methods of residual stress reconstruction, their implementation using finite element analysis, and the measurement strategies which enable them. In general, reconstruction of residual stress fields must be formulated as an inverse problem, which can usually be solved using stress basis functions. However, prior knowledge of the form of the residual stress field and/or underlying eigenstrain distribution often allows the problem to be reduced such that inverse methods become unnecessary, greatly simplifying the analysis. Two examples of when residual stress field reconstruction can be simplified in this way are given.
Influence of Gradients in the Elastic Anisotropy on the Reliability of Residual Stresses Determined by the Hole Drilling Method
Authors: Niehuesbernd Jörn , Bruder Enrico , Müller Clemens
Published: August 2014

Metal forming processes often involve large strain gradients which results in heterogeneous deformation and consequently residual stresses. Furthermore the strain gradients also generate variations in the deformation texture and related properties. For materials with a significant crystallographic elastic anisotropy such as ferritic steel, these textures may have a substantial effect on the reliability of the determination of residual stresses. In the present investigation this influence is examined for the hole drilling method by a combination of experiments and finite element simulations.
Investigation of Influence Factors on Residual Stress Determination within Coated Surfaces in Consideration of the Differential and Integral Method
Authors: Weidmann Peter , Weber Ulrich , Schmauder Siegfried , Martínez García Venancio
Published: August 2014

To improve the surface behavior of metal structures, like wear-and heat resistance or hardness, often thermally sprayed ceramic coatings are applied. A modern technology to realize dense layers is the High Velocity Oxygen Fuel (HVOF) technique. The deposition process and necessary pretreatments can cause high residual stresses within the coating and the substrate. While tensile stresses in the brittle coating may cause cracks, compressive stress states can even improve the materials behavior. To guarantee high product quality, it is necessary to know exactly the occurring residual stresses in the metal-ceramic hybrid system. A very common measurement technique is the incremental hole drilling (IHD) method. To determine the residual stresses out of IHD measurements the differential method (DM) or integral method (IM) can be used. To investigate the influence of interfacial layers, nonlinear stresses, cracking, anisotropy, variation of coating thickness and calculation formalisms several FEM models have been build, while case sensitive calibration was used for the coated systems.
Four-Point Bending Tests to Study the So-Called Plasticity Effect on the Residual Stress Results Determined by the Hole-Drilling and Ring-Core Methods
Authors: von Mirbach David
Published: August 2014

The hole-drilling method (HDM) and ring core method (RCM) are limited to low residual stresses under 60% of the yield stress. This issue will experimentally analyze the method of adaptive calculation function, presented by the author on the ICRS9. With a four-point-bending test machine, a defined stress can be triggered between the middle bending. In this defined loading area, the strains in two load cases with the HDM and the RCM configuration were measured. With these measured strains the residual stress calculation will be analysed.
Relationship between Dislocation Density and Macro Strain of High-Heat-Load Materials
Authors: Sano Mutsumi , Takahashi Sunao , Watanabe Atsuo , Shiro Ayumi , Shobu Takahisa
Published: August 2014

A relationship between dislocation density and macro strain was investigated for GLIDCOP, dispersion-strengthened copper with ultra-fine particles of aluminum oxide. The dislocation density was estimated by applying the Warren-Averbach method to a diffraction profile measured using synchrotron radiation.
Characterization of Residual Stresses and Accumulated Plastic Strain Induced by Shot Peening through Simulation of Instrumented Indentation
Authors: Li Yu Gang , Kanoute Pascale , François Manuel
Published: August 2014

In this study, a method based on finite element (FE) simulation was proposed for characterizing simultaneously residual stresses (RS) and accumulated plastic strain (PP) induced by shot peening process. Through a series of simulations of instrumented indentation, contour plots of several parameters, as maximum load, contact hardness and contact stiffness, were computed. By superposing them pair-wisely, RS and PP mixed together could be characterized simultaneously. In order to verify the method, several simulations with different combinations of RS and PP were performed. Results showed that the method is promising but remains to be tested on experimental acquisitions.
Application of Local Current Pulses for Determination and Control of Residual Stresses
Authors: Lobanov Leonid , Pivtorak Vyacheslav , Paschin Nikolay , Savitsky Viktor , Tkachuk Galina
Published: August 2014

An electrode system for inducing a high density pulsed electric current (PEC) into the material for residual stresses (RS) relaxation has been proposed. A new non-destructive technology for determination of RS using electron speckle interferometry in combination with a local PEC treatment has been developed. Application of PEC at increased power parameters was investigated for control of stressed state of welded structures used in aircraft engineering. Results of practical application of the developed technologies and equipment are presented.
Characterization of Micrometric and Localised Residual Stresses on Amorphous Materials Using Dispersion of Surface Acoustic Waves
Authors: Duquennoy Marc , Ouaftouh Mohammadi , Deboucq Julien , Lefebvre Jean Etienne , Jenot Frederic , Ourak Mohamed
Published: August 2014

For amorphous materials such as glass, the fragility of the material can be limited using surface reinforcement by chemical tempering. The principle of chemical tempering consists in forming a superficial compression layer on the surface by immersing the glass in a solution of molten potassium nitrate. In this study, dispersion of surface ultrasonic waves caused by the presence of residual surface stresses was studied. The thickness and the level of the stressed cortical zones were estimated using an inverse method.
Neutron Diffraction Strain Measurement during TIG Welding
Authors: Reisgen Uwe , Sharma Rahul , von der Heydt Jana
Published: August 2014

Development of hot cracks during welding of austenitic materials is a challenge which must be coped with when a suitable welding method is to be chosen. Boundary conditions about hot crack formation are not sufficiently known. One factor is the state of strain during welding. Therefore strain is determined via neutron diffractometry next to the fusion line during welding. This evaluation shall allow to draw conclusions about the influence of the state of thermal strain on the hot crack formation.
Neutron and X-Ray Diffraction Residual Stress Measurements in Aluminium Alloys MIG Welded T-Joints after Friction Stir Processing
Authors: Nobre João P. , Batista António Castanhola , Kornmeier Joana R. , Costa José D. , Loureiro Altino , Jesus Joel S.
Published: August 2014

Friction Stir Processing (FSP) is a relatively new post-processing technique. Fatigue strength of MIG fillet welds of aluminium alloys can be substantially improved using FSP. Beyond other properties intrinsically tied to fatigue life, especially attention should be paid to the effect of the final residual stress state. In this study the residual stress distribution in T-joints of two aluminium alloys was determined by Neutron and X-ray diffraction. FSP effect on the residual stress state and fatigue life was analysed.
Local Stress Analysis in an SMA during Stress-Induced Martensitic Transformation by Kossel Microdiffraction
Authors: Bouscaud Denis , Berveiller Sophie , Pesci Raphaël , Patoor Etienne , Morawiec Adam
Published: August 2014

The Kossel microdiffraction in a scanning electron microscope allows for local stress determination. This technique has been applied to monitor stress evolution within grains of austenite in the course of martensitic transformation in a shape memory alloy. Kossel diffraction patterns were recorded during in situ tensile straining of Cu-Al-Be alloy. These innovative measurements show large stress heterogeneities between grains, with the stress ratio exceeding two. As martensite variants are stress-induced, shear stress components appear in individual grains of austenite.
Welding Residual Stress Distribution of Quenched and Tempered and Thermo-Mechanically Hot Rolled High Strength Steels
Authors: Schaupp Thomas , Schröpfer Dirk , Kromm Arne , Kannengiesser Thomas
Published: August 2014

Beside quenched and tempered (QT) high strength steels advanced technologies in steel manufacturing provide steels produced by the thermo-mechanical controlled process (TMCP) with yield strength of 960 MPa. These steels differ in the carbon and micro-alloying element content. With variation of heat control TIG-welded dummy seams on both steel types were performed. Analyses concerning microstructure and residual stress evolution due to welding showed typical stress distributions according to common concepts. Yet, the TMCP-steel shows higher residual stresses than the QT-steel.
Residual Stresses in Multi-Pass Butt-Welded Tubular Joints
Authors: Hempel Nico , Nitschke-Pagel Thomas , Dilger Klaus
Published: August 2014

In this study, the mechanics of the residual stress development in multi-pass butt-welded joints of ferritic-pearlitic steel pipes are investigated. Therefore, the effects of the welding process and its parameters, as well as the impact of the preheating temperature on the residual stress state are studied by determining the temperature profile during welding and performing X-ray diffraction measurements on the pipes inner and outer surfaces. Additionally, residual stress depth distributions are determined using the incremental hole-drilling method. The residual stress distributions can be explained by phase transformations and thermal shrinkage, the latter being the governing mechanism in the tubular geometry of the welds.
Analysis of Quenching and Stretching Processes of Aluminum Alloy Thick Plates
Authors: Gong Hai , Wu Yun Xin , Yang Zhao Peng , Liao Kai
Published: August 2014

7050 aluminum alloy thick plates are usually heat treated and then aged to improve mechanical properties; however, residual stresses in the plates are developed during quenching. In this study, the influences of non-uniform factors on residual stresses in aluminum alloy thick plates during the quenching and stretching processes are studied. The results show strong inhomogeneity of the residual stress distribution in the plates, and the length of influenced area of the stretched plate is discussed.
Evolution of Residual Stresses during Short Time Nitriding of 33CrMoV12-9 Steel Grade
Authors: Fallot Guillaume , Jegou Sebastien , Barrallier Laurent
Published: August 2014

The evolution of residual stresses during short time gas nitriding of 33CrMoV12-9 steel grade is studied. It aims understanding the influence of nitriding parameters (temperature and nitriding potential) on the generation and evolution of residual stresses in the very first stage of nitriding. The samples are gas nitrided using a thermobalance during 2h30 and 5 hours for various temperatures and nitriding potentials. Residual stress analyses are carried out by laboratory X-ray diffraction.
Effect of Preloading on Local Residual Stresses Induced by Laser Surface Hardening of Steel
Authors: Kostov Vladimir , Gibmeier Jens , Lichtenberg Klaudia , Wanner Alexander
Published: August 2014

The effect of defined preloading in the tensile and compressive regime on the near surface (residual) stress distributions, which result from laser surface hardening, is systematically studied in-situ, i.e. under the applied preload and after unloading. Samples made of steel grade AISI 4140 are defined surface hardened by means of a high-power diode laser (HPDL) system during uniaxial compressive elastic loading at-300 MPa as well as during uniaxial elastic tensile loading at 300 MPa using a custom designed 4-point-bending device, which can be mounted on an X-ray diffractometer. The results of X-ray stress analysis were compared to data derived for a sample state unaffected by any preload. Without external loading compressive residual stresses are induced inside the process zone that are balanced by tensile residual stresses outside this zone. The investigations show that external loading in the tensile and compressive regime has a strong impact on the resulting lateral residual stress distribution in loading direction. The results further indicate that undesirable tensile residual stresses outside the process zone can even be suppressed by using a defined appropriate preloading in the tensile regime.
Matrix Method for X-Ray Stress Measurement in Single Crystals, and the Rational Planning of the Measurements
Authors: Ortner Balder
Published: August 2014

With the so-called matrix method stress calculation from x-ray diffraction measurements is much easier than it used to be with older methods. The matrix method is also well suited to optimize the choice of reflections (hkl) to be measured in order to obtain the best results with least experimental effort. Pseudocodes for the stress calculation are given.
Study of Residual Stresses in Bimetallic Work Rolls
Authors: Neira Torres Ingrid , Gilles Gaëtan , Tchoufang Tchuindjang Jerome , Lecomte-Beckers Jacqueline , Sinnaeve Mario , Habraken Anne Marie
Published: August 2014

An experimental campaign of compression tests, differential thermal analysis (DTA), differential scanning calorimetry (DSC), dilatometry and microstructure analysis has been performed, as well as the identification of the material data set for finite element (FE) analysis of bimetallic rolls. This article numerically investigates the stress and strain fields after the cooling stage and it checks their effect on the subsequent heat treatment step. As bimetallic rolls have a different material for core and shell, the effect of the roll size and the shell thickness on residual stresses is also studied.
Analysis of Residual Stress in Stress Harps of Grey Iron by Experiment and Simulation
Authors: Schmidt Pål , Ru Lin Peng , Davydov Vadim , Lundberg Mattias , Ahmad Maqsood , Vuoristo Taina , Bäckström Daniel , Johansson Sten
Published: August 2014

Stress harps with bars of different size were used to study residual stresses due to different cooling rate during casting of a grey iron. Finite element (FE) simulations were performed to predict residual stresses from the casting process and the effect of a stress relieving heat treatment. Intended for validating the simulations, neutron diffraction (ND) and hole drilling methods were used to measure the residual stress distribution through the thickness and in a thin surface layer, respectively. Good agreement between the FE simulations and ND measurements is observed for the annealed harp and the normal and transverse directions of the as cast harp. Discrepancy occurs in the axial direction and especially in the side bars of the as cast harp for which the simulation shows much higher compressive residual stresses. The observed difference between the different techniques was discussed with respect to the characteristics of the different methods.
Local Global Method for the Prediction of Surface Residual Stresses in 3D Turning
Authors: Valiorgue Frédéric , Girinon Mathieu , Feulvarch Eric , Rech Joël , Gilles Philippe
Published: August 2014

Numerical simulation of turning is still one of the best solutions to understand and improve such a process. Since many years, researchers have tried to use several numerical approaches to go round the difficulties and to set up reliable models (Lagrangian, ALE,…). Currently no perfect complete solution is available and it is time to introduce dedicated models prone to simulate partially the phenomena in order to reach specific conditions linked with real industrial problematics. This paper will present a 3D local global method set up to predict surface residual stresses in finish turning. This approach uses two kinds of simulations. A first one that allows reaching thermo mechanical steady state around the cutting edge and the chip area. A second one which sequences the application of the extracted thermo mechanical fields onto the real workpiece surface. The obtained results concerning the residual stresses fields will then be compared with the ones recorded experimentally.
Effect of Built-Up Edge Formation on Residual Stresses Induced by Dry Cutting of Normalized Steel
Authors: Kümmel Johannes , Gibmeier Jens , Schulze Volker , Wanner Alexander
Published: August 2014

The tool and workpiece surface layer states of the tribosystem uncoated WC-Co cutting tools vs. normalised SAE 1045 workpiece material are studied in detail for a dry metal cutting process. Within the system the cutting parameters (cutting speed, feed rate, cutting depth) determine the wear state of the cutting tool and the resulting surface layer state (residual stress) in the workpiece. As the built-up edge can be used as a possible wear protecting layer [1] the influence of built-up edge and wear behaviour of the cutting tool was examined with respect to the workpiece surface layer state for knowledge based metal cutting processing. Small compressive stresses (-60-80 MPa) are induced in the surface layer, that are nearly homogeneous for the highest built-up edge, which lead to the lowest tool wear in combination with lowest cutting temperature.
Numerical Assessment of Residual Stress Induced by Machining of Aluminum Alloy
Authors: Ben Moussa Naoufel , Al-Adel Zouhayar , Sidhom Habib , Braham Chedly
Published: August 2014

A numerical approach has been developed to predict the near surface residual stresses induced by turning in orthogonal cutting configuration of aluminum alloy AA7075-T651. This approach is based on a Lagrangian formulation using the finite element software Abaqus–Explicit. The calculated residual stress profiles were validated by experimental measurements using X-ray diffraction method on samples turned under different cutting conditions. Using this method, the effect of the cutting speed and the feed on the machining residual stress has been established.
Measurement of Complementary Strain Fields at the Grain Scale
Authors: Chow Wang , Solas Denis , Puel Guillaume , Perrin Eric , Baudin Thierry , Aubin Veronique
Published: August 2014

In this study, a monotonous mechanical test is performed on a sample in Al-alloy containing about twenty-five grains. During this test, both the total and elastic intragranular strain fields are measured at the same time. The former field is observed by digital image correlation technique while the latter one is measured by X-ray diffraction. The strain fields obtained are then dedicated to identify the parameters of a crystalline constitutive model, using finite element simulation.
Real Structure of Milled Inconel 738LC Turbine Blades
Authors: Pala Zdenek , Kolařík Kamil , Beranek Libor , Čapek Jiří , Kyncl Jiří , Mušálek Radek , Ganev Nikolaj
Published: August 2014

Machining of nickel super-alloys is difficult since mechanical hardening and, consequently, extreme tool wear occur. In the case of turbine blades, castings can no longer meet stringent requirements for precision; hence, they are being ground or milled in order to comply with the demanded dimensions. In this contribution, castings made of Inconel 738LC were machined by four axis milling. The resulting surface of gas turbine blades are characterized by several surface integrity parameters with respect to the structural inhomogeneities caused by mutual effect of plastic deformations and thermal fields during the cutting process. Moreover, the impact of effective contact area of the cutter was considered as well. It will be shown that ideal machining parameters viewed from the standpoint of surface roughness and economy of the whole machining process can lead to appreciable tensile normal stresses.
Residual Stress Gradients in AISI 9254 Steel Springs Submitted to Shot Peening and Heat Treatment for Increased Fatigue Resistance
Authors: Vilela Costa Larissa , Gonçalves Carneiro José Rubens , Pinto Coelho Catalão Rogério , Ribas Omar Khayyam , Brito Pedro
Published: August 2014

The presence of surface and subsurface residual stresses in steel components has a significant influence on fatigue resistance. In the present work, surface modification of AISI 9254 steel coil springs by heat treatment and multiple shot-peening procedures was investigated. Samples were characterized in the as-coiled, quenched, quenched and tempered, as well as submitted to single and double shot peening treatments. Depth resolved residual stress profiles were determined by X-ray diffraction combined with electrolytic dissolution of the steel. Fracture analysis was performed subsequent to fatigue tests by scanning electron microscopy. It was possible to show that double shot peening led to an increase in compressive stresses in the immediate sub-surface region, which improved fatigue resistance relative to the other tested conditions.
Evaluation of Welding Residual Stresses Using Diffraction Spot Trace Method
Authors: Suzuki Kenji , Shobu Takahisa , Shiro Ayumi , Zhang Shuo Yuan
Published: August 2014

A diffraction spot trace method (DSTM) is very useful to measure internal stresses of materials with coarse grains. In this study, validity of the DSTM was examined using high energy synchrotron X-ray of 70 keV. The specimen was a welded plate of austenitic stainless steel (SUS316L). The thickness of the specimen was 9 mm. The improved spiral slit system was used, and PILATUS was used as an area detector. It was difficult to detect the high energy X-rays due to the reduction of counting efficiency of the PILATUS. However, the residual stress map of the welding specimen was obtained by long exposure time. The residual stresses of the welding specimen were simulated by a finite element method (FEM). The outline of the residual stress measured by the DSTM coincided with that by the FEM.
Influence of Tempering Conditions on Shot-Peened Tool Steel Components In-Depth Residual Stress Profiles
Authors: Cecchin Diego , Kobza Evgeny , Cazzolli Marco , Azanza Ricardo Cristy Leonor , D'Incau Mirco , Bandini Michele , Scardi Paolo
Published: August 2014

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.
Process Induced Residual Stress Effect on Fatigue Lifetime of Automotive Steel Components
Authors: Merhy Elias , Niane Ngadia Taha , Weber Bastien , Bristiel Philippe
Published: August 2014

Metal Active Gas (MAG) welding process of steel sheets generates, in the vicinity of the welding joint, the well-known Heat Affected Zone (HAZ) in which the material presents more microstructural defects compared to the original metal. Since high cycle fatigue is largely dependent on the material microstructure features, the HAZ is considered as the weakest zone under high cycle fatigue loading. In addition, the welding causes, in the Heat Affected Zone, irreversible plastic strains that induce important residual stress fields in this critical zone of the structure. Therefore, in order to properly predict the high cycle fatigue life time of the welded automotive components, it is of primordial importance to first identify and then consider, if necessary, the welding induced residual stress field in the structure modeling. In this work, it is found that residual stresses have non-negligible impact on high cycle fatigue lifetime, while its effect is minor in the low cycle fatigue domain.
On-Chip MEMS-Based Internal Stress Actuated Structures for the Mechanical Testing of Freestanding Thin Film Materials
Authors: Vayrette Renaud , Coulombier Michael , Pardoen Thomas , Raskin Jean Pierre
Published: August 2014

An on-chip suite of MEMS-based mechanical testing structures has been developed to extract the mechanical properties of freestanding thin films under tensile loading. The working principle relies on the use of high tensile internal stress within an actuator beam to deform a specimen beam made of another material owing to the etching of an underlying sacrificial layer. In order to control the deformation rate imposed during the etching process, the rectangular shape of actuator beam design has been recently upgraded to a tapered shape. The deformation rate is estimated from the modelling of the two extreme cases defining the upper and lower limit. The proof of concept is demonstrated experimentally from the investigation of the mechanical response of 100 nm-thick freestanding copper thin films deposited by e-beam evaporation.
Investigations on Thermal Stresses of a Graded Ti(C,N) Coating Deposited on WC-Co Hardmetal
Authors: Ramos-Moore Esteban , Espinoza Carlos , Coelho Rodrigo S. , Pinto Haroldo , Brito Pedro , Soldera Flavio , Mücklich Frank , Garcia Jose Luis
Published: August 2014

We investigated the stress behaviour of Ti(C,N) coatings deposited on WC-Co substrates during an individual thermal cycle. The stress analyses were performed in-situ by energy dispersive X-ray diffraction using a white synchrotron beam. The stresses were determined using the sin2ψ method combined with scattering vector measurements at the strain-free ψ-tilt, in order to avoid the effect of the chemical C/N gradient on the strain distributions over sin2ψ. It was found that compressive stresses induced by top blasting on the coating are released after the individual thermal cycle. During heating and cooling, part of the Ti(C,N) coating was oxidized into a TiO2 rutile phase. Stress analysis was also performed in this phase in order to evaluate the influence of oxidation on the residual stress of the coating. The obtained results can support the design of coated tools with improved properties at interrupted cutting operations by understanding the role of thermal cycling on the stresses of Ti(C,N) coatings.
Stress Development and Adhesion in Hydrogenated Nano-Columnar Pd and Pd/Ti Ultra-Thin Films
Authors: Verma Neha , Böttger Amarante J.
Published: August 2014

Stress development upon hydrogenation of about 100 nm thick palladium layers on thermally oxidized silicon wafers with and without an intermediate Ti layer is studied. Stress developed is investigated by in-situ XRD in H2/N2(hydrogenation) and N2(dehydrogenation) gas at RT. The method adopted to measure residual stress involved specimen omega- (ω) and psi- (ψ) tilting, on two different diffractometer geometries (focusing and parallel). For the stress analysis, the presence of intrinsic elastic anisotropy of the film is considered. Upon hydrogenation α-Pd transformation to β-PdHoccurs and because of the constrained in-plane expansion a large compressive stress develops. Scanning electron microscopy shows that films with a Ti intermediate layer adhere better to the substrate upon hydrogen cycling, whereas, pure Pd film start cracking and buckling.
Time-Resolved X-Ray Stress Analysis in Multilayered Thin Films during Continuous Loading: Use of 2D Remote Detection
Authors: Guillou Raphaëlle , Renault Pierre-Olivier , Le Bourhis Eric , Goudeau Philippe , Godard Pierre , Geandier Guillaume , Faurie Damien , Thiaudière Dominique , Mocuta Cristian
Published: August 2014

Synchrotron X-ray diffraction is a powerful tool to analyse the mechanical behavior of multiphase materials due to its selectivity. Simultaneous stress analysis of both phases of a W/Cu thin multilayer has been performed during a continuous biaxial loading on DiffAbs beamline at SOLEIL synchrotron (France). The use of a 2D detector with a large sample-detector distance is shown to give relatively accurate applied stress analysis even if only a small part of the usual ψ range of the sin2ψ method is considered. The results show the failure of the thin film multilayer while the W components are still under a strong compressive stress state of-3 GPa. It is concluded that the mechanical behavior is in fact mainly governed by the residual stress state.
Influence of Surface Mechanical Attrition Treatment (SMAT) on Oxidation Behavior of 316L Stainless Steel at 650°C
Authors: Benafia Souhail , Retraint Delphine , Panicaud Benoit , Grosseau-Poussard Jean Luc
Published: August 2014

In this paper, the effects of Surface Mechanical Attrition Treatment on the high-temperature oxidation of AISI 316L austenitic stainless steel are investigated. Samples treated with different conditions were oxidized at 650°C in order to study the effect of this type of nanocrystallisation on the oxidation resistance of the alloy concerned. X-ray diffraction and in-situ Raman spectroscopy were used to identify the oxides formed at the surface. The results indicate the presence of hematite and chromium oxides. Experimental results obtained by Raman spectroscopy were also used to study the stress evolution in Cr2O3films during isothermal conditions.