bluuebunny/crossref_metadata_2025_split huggingface dataset:
Anelastic relaxation and structure of ternary Fe–Al–Me alloys with Me=Co, Cr, Ge, Mn, Nb, Si, Ta, Ti, Zr
Authors: Golovin I. S. , Strahl A. , Neuhäuser H. 
Published: December 2013

AbstractThe anelasticity of binary Fe–Al and ternary Fe–Al–Me (Me=Co, Cr, Ge, Mn, Nb, Si, Ta, Ti, Zr) alloys has been studied by mechanical spectroscopy in the Hz and kHz ranges. Relaxation peaks due to point defects – Snoek effect (S) with carbon interstitial jumps, carbon-vacancy complexes (X peak), Zener effect (Z), dislocations (D), and grain boundaries (GB) – are observed and their changes with addition of the third element are used to corroborate the respective proposed relaxation mechanisms, taking account of the changes of structure and order in the alloys which contain up to 5Co, 25Cr, 25Ge, 5Mn, 0.3Nb, 25Si, 6Ta, 4Ti, and 15Zr (all in at.%), respectively. In addition, some data of ordering temperatures, Curie temperatures, and hardness are provided for several alloys.
Temperature dependence of lattice mismatchand volume fraction of a fourth-generation monocrystalline nickel-based superalloy
Authors: Diologent Frédéric , Caron Pierre , d'Almeida Thierry , Chambreland Sylvain , Jacques Alain , Bastie Pierre 
Published: December 2013

Abstract
The strain distribution in a new generation nickel-based single crystal superalloy has been determined in the temperature range 293K–1598K. Measurements have been performed using diffraction of high energy synchrotron radiation (150keV, λ = 0.008 nm) to determine the variations with temperature of the γ/γ′ lattice mismatch and of the γ′ volume fraction. The chemical segregation at the dendrite scale and the internal stress induce a large range of values for the lattice mismatch. The measurements of the γ′ volume fraction determined by X-ray diffraction are in agreement with those obtained by atom probe tomography, image analysis or computation.
Filtration resistance during pressure filtration tests of liquid aluminium alloys
Authors: Cao Xinjin 
Published: December 2013

AbstractPrefil Footprinter, a portable pressure filtration instrument, is usually employed to detect liquid metal quality. However, no investigations have ever been done to determine overall filtration resistance and resistance of the “clean” filter media. Based on the identification of flow behaviour using the derivative methods, classic filtration equations have been effectively used to estimate total filtration resistance for the first time. The variations of overall resistance during filtration provide a new approach to understand filtration behaviour. The resistance values of the “clean” filter media have been obtained for the first time. An innovative method has been developed to obtain the resistance of the “clean” filter media through the backward extrapolation of the overall filtration resistance versus filtrate weight or filtration time curves over the steady stages operating in incompressible cake mode.
Microstructure of a Damascene sabre after annealing
Authors: Reibold Marianne , Levin Alexander A. , Meyer Dirk C. , Paufler Peter , Kochmann Werner 
Published: December 2013

Abstract
X-ray phase analysis combined with high-resolution electron microscopy of samples taken from a genuine Damascus sabre after annealing for 24h at 400°C and 800°C followed by slow cooling down to room temperature has led to a better insight into the nature of cementite nanowires, which have been discovered recently. According to the present study, nanowires remained after 400°C annealing, but disappeared after heat treatment at 800°C and subsequent cooling down. On the other hand, perlitic cementite has been retained qualitatively after the same treatment. Knowing that the exceptional mechanical properties of Damascene blades disappear after annealing, the present results suggest a significant influence of the nanowires upon these features.
Multiwall carbon nanotubes-based composites – mechanical characterization using the nanoindentation technique
Authors: Olek M. , Kempa K. , Giersig M. 
Published: December 2013

Abstract
We report on mechanical properties of multiwall carbon nanotubes (MWNTs)-polymer composites using the nanoindentation technique. The nanoindentation experiments conducted on thin films containing MWNTs revealed that the presence of nanotubes does not affect the nanomechanical properties of the composites. Even a layer-by-layer assembly of MWNTs with a high concentration and a homogeneous distribution of carbon nanotubes does not ensure reinforcement of the composites. For that reason, we synthesized and utilized carbon nanotubes with a silica shell. Nanohardness and Young's modulus have been found to increase strongly with increasing content of these nanotubes in the polymer matrix. The silica shell on the surface of a nanotube enhances its stiffness and rigidity. Our composites, at 4wt.% of the silica-coated MWNTs, display a maximum hardness of 12020MPa and a Young's modulus of 91GPa. These are, respectively, 2 and 3 times higher than those for the polymeric matrix.
Mechanism of quasi-viscous flow of zinc single crystals
Authors: Pieła Krzysztof 
Published: December 2013

Abstract
This paper reports the results of mechanical investigations (tensile and relaxation tests), geometrical measurements as well as macro- and microscopic (slip traces) observations of zinc single crystals in the ‘hard’ orientation (from the line – of the standard triangle) tested in the temperature range 523–673K. Consideration of the experimental data lead to the conclusion that the quasi-viscous flow of crystals results from localized coarse slip in the basal system occurring in the structure of uniformly distributed slip in the 1st order prismatic (and/or the 1st order pyramidal) systems. The proposed mechanism explains the high strain-rate sensitivity and the ‘jerky’ character of the flow of the crystals.
Cooperating twin robots form a new X-ray diffractometer for stress analysis
Authors: Hessert Roland , Satzger Wilhelm , Haase Alfried , Schafmeister Achim 
Published: December 2013

Abstract
X-ray diffraction measurements on large components with complex geometry are needed in industrial applications requiring the non-destructive characterization of the near-surface material condition in terms of residual stresses, work hardening, phase transformation and formation of reaction compounds. Because many regions of interest on these components are not accessible with conventional laboratory or even mobile X-ray diffractometers, a novel center-free diffractometer with two cooperating robots named “Charon XRD” has been developed at MTU Aero Engines.
Two six-axis robots are synchronized using a special optical measuring system to achieve the highest positioning accuracies. This paper describes the actual design and operating mode of Charon XRD, its current and potential functionality, and presents calibration and reference measurements, along with results on aero-engine high-technology components like bladed integrated disks.
Cube textured tapes for use in YBa2Cu3O7–δ-coated conductor applications
Authors: Obst Bernhard , Nast Rainer , Kotzyba Gunter , Wetscher Florian 
Published: December 2013

Abstract
YBa2Cu3O7 is a high-temperature superconductor. Due to its complex lattice structure, belonging to the layered perovskite family, a strong biaxial texture of the grains is necessary to achieve technically relevant currents. In this paper, coarse-grained Ni, Ni-4at.% W, and electrolytic copper (E-Cu) obtained from swaged rods, and ultra-fine grained E-Cu produced by equal channel angular pressing, were thermo-mechanically processed. The development of the primary recrystallisation of the cube texture was studied and compared to determine the suitability of these materials as lattice-matched templates for coated conductor applications. Electron backscatter diffraction was performed to measure the texture and microstructure at various deformation levels and annealing temperatures. The texture sharpness formed in E-Cu with a coarse-grained starting microstructure proved superior, and it correlates with an anomaly observed in the temperature sensitivity of the flow stress in tensile tests, arising from crystal rotations.
Cavitation erosion of advanced ceramics in water
Authors: Litzow Ulrike , Gahr Karl-Heinz Zum , Schneider Johannes 
Published: December 2013

Abstract
The performance of advanced ceramics under cavitation loading in distilled water was studied by using a laboratory test with vibration-induced cavitation following the pattern of the ASTM standard G32–92. The hardened and tempered martensitic steel 100Cr6 was used as a reference. The aim was to identify mechanisms and the effects of important microstructural parameters on damage of polished Al2O3, Al2O3–ZrO2, ZrO2 and SiC ceramics. Results showed that surface damage of brittle ceramics was mainly dominated by intergranular fracture, followed by detachment of single grains or fragments of them. Both incubation time and erosion rate were affected by the amount of initial surface cavities, grain sizes and secondary phases at grain boundaries.
Microstructure and fatigue strength of the roller-bearing steel 100Cr6 (SAE 52100) after two-step bainitisation and combined bainitic–martensitic heat treatment
Authors: Vetters Hermann , Dong Juan , Bomas Hubert , Hoffmann Franz , Zoch Hans-Werner 
Published: December 2013

Abstract
Possible processes for shortening the heat treatment of roller-bearing steels in the lower bainitic range were investigated by computer assisted dilatometric experiments and by practical heat treatment process simulations. Several processes were evaluated and used on the steel 100Cr6 (SAE 52100). The microstructures achieved have been investigated by metallography, X-ray analysis and electron microscopy. Influences on hardness, as well as on the fatigue strength were examined. No loss in hardness was achieved and the fatigue strength, determined by rotating bar fatigue tests, was enhanced significantly by the shortened treatments, particularly by the use of the two-step bainitic treatment. The results indicated that small amounts of retained austenite, homogeneously dispersed on a sub-microscopic scale, as obtained during various treatment cycles, have influenced the fatigue strength. By means of the processes evaluated the heat treatment time can be shortened to about 10–25% of the duration of complete bainitisation in the lower range.
Description of flow curves over wide ranges of strain rate and temperature
Authors: El-Magd Essam , Treppman Christoph , Korthäuer Marcus 
Published: December 2013

Abstract
The relation between flow stress, strain rate and temperature is described by the same model over wide ranges of strain rates and temperatures. The model is developed on the basis of experimental data for flow curves of TiAl6V4, AA7075 (AlZnMgCu1.5) and steel Ck45N at temperatures varied between room temperature and 500°C, 900°C or 1000°C, respectively. The strain rate values cover the range between 10−3 and 8×10+3s−1. The model considers three simultaneously acting deformation mechanisms: creep deformation at high temperatures and low strain rates, thermally activated glide at low temperatures, and moderate to high strain rates and damping controlled deformation at very high strain rates. The model provides the data required for the simulation of high speed metal cutting and forming processes.
On the Hall–Petch relation between flow stress and grain size
Authors: Blum W. , Li Y. J. , Chen J. , Zeng X. H. , Lu K. 
Published: December 2013

Abstract
Data of flow stresses σ for pure Cu with ultrafine grains with grain size d ≍ 0:35 μm produced by severe plastic deformation and grains of conventional size obtained in the range of homologous temperatures T
hom from 0.22 (room temperature) to 0.33 are compared to data for hardnesses H for Cu of various grain structures from single crystalline to d = 0:01 μm measured by nanoindentation at room temperature. The two sets of data appear to be consistent when σ ≍ H=3. At room temperature the Hall – Petch relation holds, i. e., the flow stress increases monotonically with decreasing grain size by Δ σ ∝ d
−0.5. At elevated T
hom the saturated flow stress decreases when the grains become ultrafine. The transition from hardening to softening by grain boundaries in the saturation stage is discussed on the basis of a simple statistical dislocation model considering the influence of grain boundaries on the balance between generation and annihilation of dislocations.
Effect of a low frequency electromagnetic field on the direct-chill (DC) casting of AZ80 magnesium alloy ingots
Authors: Guo Shijie , Le Qichi , Zhao Zhihao , Han Yi , Cui Jianzhong 
Published: December 2013

Abstract
The effects of a low frequency electromagnetic field applied during semi-continuous direct-chill casting on AZ80 ingots were investigated. The experiments were performed both in the absence and in the presence of the electromagnetic field. In contrast to the ingot cast in the conventional process, the microstructure of the ingot was significantly refined by the electromagnetic field and a high degree of grain refinement was realized when the operating frequency was at 22Hz. The ingot exhibited a relatively increased and uniform distribution of Vickers hardness and decreased segregation of Al when the operating frequency of the electromagnetic field was in the range of 15–30Hz.
Synthesis and characterization of MgAlON–BN composites
Authors: Zhang Zuotai , Li Wenchao , Wang Xidong , Seetharaman Seshadri 
Published: December 2013

Abstract
In the present paper the Gibbs energy of formation of MgAlON was evaluated, and on this basis the phase stability diagram of Mg – Al – O – N – B was established. Dense magnesium aluminium oxynitride – boron nitride (MgAlON – BN) composites with 0 – 30 vol.% BN were synthesized by hot pressing in the temperature range 1750 – 1850 °C in the phase stability region. The phase compositions of the composites analyzed by X-ray diffraction indicated that the main phases were MgAlON and h-BN and no impurities were found. The microstructures of the composites analyzed by transmission electron microscopy, scanning electron microscopy, and high-resolution electron microscopy showed that the MgAlON did not react with BN, and the latter was distributed on the grain boundary of MgAlON homogeneously. Excessive BN (> 20 vol.%) resulted in a discontinuous microstructure for MgAlON. A matrix-flushing method was employed in the quantitative X-ray diffraction analysis for the multi-component MgAlON – BN composites. The results showed that the relative MgAlON content decreased in the process of sintering MgAlON – BN composites. Thermodynamic analysis showed that some Al2O3, AlN, and MgO escaped under the reaction conditions. The lattice parameters of MgAlON in the composites have also been evaluated.
Mechanical properties of rope-reinforced aluminium extrusions under quasistatic loading conditions
Authors: Weidenmann Kay André , Fleck Claudia , Schulze Volker , Löhe Detlef 
Published: December 2013

Abstract
Compound-extruded unidirectionally reinforced lightweight profiles are a novel class of materials for the construction of load-bearing structures. In this paper, investigations of the reinforcing effect of ropes in compound-extruded aluminium profiles tested under quasistatic loading conditions are presented. In particular, the investigations lead to a characterisation of the interface between matrix and reinforcing element, as the compound's internal load transfer is a crucial factor in the overall mechanical properties. It could be shown that – in addition to a form fit – a diffusional bond evolves. Both Young's modulus and tensile strength could be increased by using a rope reinforcement. Furthermore, the results attained are compared to a theoretical model which was adapted to the deformation behaviour of compounds containing a single reinforcement.
Density and atomic volume in liquid Al–Fe and Al–Ni binary alloys
Authors: Plevachuk Yuriy , Egry Ivan , Brillo Jürgen , Holland-Moritz Dirk , Kaban Ivan 
Published: December 2013

Abstract
The density of liquid Al – Fe and Al – Ni binary alloys have been determined over a wide temperature range by a non-contact technique combining electromagnetic levitation and optical dilatometry. The temperature and composition dependences of the density are analysed. A negative excess volume correlates with the negative enthalpy of mixing, compound forming ability and chemical short-range ordering in liquid Al – Fe and Al – Ni alloys.
Superplastic deformation behavior of a spray-deposited eutectic NiAl/Cr(Mo) alloy doped with Dy
Authors: Du Xinghao , Wu Baolin , Huang J. C. 
Published: December 2013

Abstract
The tensile deformation behavior at elevated temperatures and the associated mechanisms are investigated for hot isostatically pressed NiAl-28Cr-5.9Mo-0.1Dy fabricated through spray forming. Superplasticity is observed at above 1323 K under an initial strain rate lower than 10−3 s−1 with an m value of 0.5. The activation energies for superplastic flow are found to be half of that for self-diffusion in NiAl. Grain boundary sliding between NiAl and adjacent NiAl or Cr(Mo) grains with local range accommodation, i. e., dynamic recovery, is suggested to be responsible for the superplastic deformation of the alloy.
The influence of Nd on the corrosion behavior of electroless-deposited Fe–P
Authors: Meng Yan , Wang Ling-Ling , Huang Gui-Fang , Huang Wei-Qing , Zou Bing-Suo 
Published: December 2013

Abstract
Fe – Nd – P layers were prepared by electroless deposition. Discussed in this paper is the influence of the rare earth element Nd on the deposition rate, mixed potential, anti-corrosion performance, structure, and surface morphology of the deposit. The results show that the deposition rate increases with the addition of Nd and the increment can be as high as 30 %. The addition of Nd also improves the homogeneity of the deposit, eliminates pores, and reduces the particle size. Electroless Fe – P deposits incorporated with Nd also exhibit significantly improved anti-corrosion performance, especially in alkaline media.
Microstructure and mechanical properties of AZ91D alloy prepared by a semi-solid diecasting process
Authors: Du X. H. , Zhang E. L. , Wu B. L. 
Published: December 2013

Abstract
Semi-solid processing has been combined with die-casting for the magnesium alloy AZ91D. The microstructure of the semi-solid diecast AZ91D has been examined by optical microscopy and scanning electron microscopy. No pores were visible under optical microscopy, indicating a very low porosity. Mechanical properties of the semi-solid diecast AZ91D alloy have also been tested. High ultimate tensile strength and elongation have been achieved due to the low porosity and the fine microstructure. The fracture surfaces have been investigated by scanning electron microscopy in order to reveal the fracture mechanism. A typical inter-granular fracture surface was observed, indicating that the alloy fails in a brittle manner. The vertical-section microstructure of the fractured sample has indicated that the crack mainly propagates along the grain boundaries through the brittle fracture of the eutectic phase or the interface decohesion of the primary Mg phase and the eutectic phases.
Grain refinement and texture formation in torsion deformed NiAl
Authors: Klöden Burghardt , Rybacki Erik , Oertel Carl-Georg , Skrotzki Werner 
Published: December 2013

Abstract
Torsion at elevated temperatures and pressures was used to severely deform the intermetallic compound NiAl. The microstructure and texture as a function of shear strain were investigated by orientation imaging microscopy and diffraction of synchrotron radiation, respectively. The results show that at high shear strains a steady state grain structure and texture develops by continuous dynamic recrystallisation. The lowest grain size achieved is in the micron range, the main texture component is {110}<100>. It is concluded that high-strain torsion may open new possibilities in terms of grain refinement, texture formation and ductilisation of NiAl.
Deformation processing of massive nanostructured materials
Authors: Wilde Gerhard , Dinda Guru Prasad , Rösner Harald 
Published: December 2013

Abstract
Deformation processing of initially polycrystalline material can lead to ultrafine-grained or even to nanocrystalline material, depending on the applied deformation route. In addition to different grain sizes, materials processed by different deformation methods also display different thermal stabilities. In order to analyze the impact of defects – particularly dislocations – near the grain boundaries, pure Pd and pure Ni have been processed sequentially by different methods. Transmission electron microscopy investigations at high resolution were conducted to characterize the microstructures of the materials. In addition, geometrical phase analysis was used to locate defects and visualize their strain fields. The results indicate that the presence of a high dislocation density at the grain boundaries increases the stability of the nanocrystalline structure against coarsening.
Multiscale modelling of nanoindentation
Authors: McGee Edward , Smith Roger , Kenny S. D. 
Published: December 2013

Abstract
The process of nanoindentation causes physical phenomena not only at the nano-scale, but at multiple length scales up to the macroscopic. We present a model that links atomistic scale molecular dynamics to a finite element model in order to extend the length scales that can be modelled. We illustrate how this has been used in some studies of nanoindentation, to test the coupled model, and secondly to compare the results to atomistic only models. These studies show that by extending the length scales, the results from the model are in closer agreement with the experiment.
Cyclic deformation behavior of deep rolled as-quenched aluminium alloy AA6110 at elevated temperatures
Authors: Juijerm Patiphan , Altenberger Igor 
Published: December 2013

Abstract
The as-quenched (solution-heat-treated) aluminium wrought alloy AA6110 (Al – Mg – Si – Cu) was mechanically surface treated (deep rolled) at room temperature. The deep rolled as-quenched AA6110 was cyclically deformed at room and elevated temperatures up to 250 °C using stress-controlled push-pull fatigue tests. Cyclic deformation behavior and Wöhler curves of the deep rolled as-quenched AA6110 have been investigated and compared to the polished condition as a reference. The effect of static/dynamic precipitation occurring during fatigue at elevated temperatures was analyzed and discussed. The stability of residual stresses as well as work hardening at elevated temperature was investigated using X-ray diffraction methods. Finally, from the S/N data, a borderline describing the effectiveness of deep rolling for different loading combinations in a stress amplitude – temperature diagram was established.
Isothermal oxidation behavior of a precipitation-hardened Pt-base alloy with additions of Al, Cr and Ni
Authors: Wenderoth Markus , Vorberg Stefan , Fischer Bernd , Völkl Rainer , Glatzel Uwe 
Published: December 2013

Abstract
The oxidation behavior of a precipitation-hardened Pt-base alloy with 12 at.% Al, 6 at.% Cr and 5 at.% Ni was examined. At high temperatures in air this alloy forms an alumina scale and a precipitate-free layer underneath, both growing according to parabolic functions of time. Small amounts of Ni embedded in the oxide scale accelerate its growth in the initial phase of oxidation. With time, oxidation is retarded due to decreasing impurity concentration and grain coarsening in the oxide scale. The interdiffusion coefficients of the scale-forming element Al in the Pt-rich solid solution matrix are estimated.