bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pressure solidification – a novel moulding technique for plastic parts with superior dimensional stability
Authors: Ehrenstein Gottfried W. 
Published: December 2013

Abstract
Sophisticated serial products require precise plastic parts that can be effectively manufactured employing the injection moulding process. However, the cooling of solid and molten material at the same time leads to high shrinkage, warpage and residual stresses. These processing characteristics determine the limits of dimensional stability that can be achieved with conventional injection moulding. A novel processing approach, in which the solidification is accomplished by pressure loading only, makes sure that these difficulties can be overcome. With this approach solidification takes place over the entire moulding at the same time. Investigations have been carried out into the viscosity, compressibility and thermal expansion of amorphous thermoplastics, which allowed evaluation of the physical pre-conditions for the novel moulding technique.
Stability of residual stresses in longitudinally and transversely deep rolled sintered iron under quasistatic and cyclic loading
Authors: Merkel Jens , Schulze Volker , Wanner Alexander , Löhe Detlef , Vöhringer Otmar 
Published: December 2013

Abstract
The residual stresses in flat coupons of sintered iron (ASC100.29) deep rolled on both surfaces were studied in the as-rolled condition and upon quasistatic or cyclic bending.
In the as-rolled condition, the stresses are compressive and exhibit a clear orientation dependence with respect to the rolling direction. Also, a significant difference between the primarily and finally deep rolled surfaces is observed, which can be attributed to the effects of specimen bending occurring during the deep rolling process.
The evolution of the residual stresses during fatigue is partly counter-intuitive: in transversely deep rolled specimens, an increase in compressive residual stresses in the transverse direction is observed within the very first loading cycle. Possible reasons for this unexpected effect are discussed.
Re-evaluation of phase equilibria in the Al–Mo system
Authors: Eumann Markus , Sauthoff Gerhard , Palm Martin 
Published: December 2013

Abstract
Phase equilibria and homogeneity ranges of the intermetallic phases in the Al–Mo system have been determined. The microstructures of samples of fixed composition and of diffusion couples were investigated by light-optical and scanning electron microscopy, the crystallographic structures and lattice constants were established by X-ray diffraction and the compositions of the phases were determined by electron probe microanalysis. In addition, transition temperatures were determined by differential thermal analysis. The homogeneity ranges of the Al-rich intermetallic phases are narrow, with about 0.1 to 0.4at.% widths. The phases and phase equilibria as established in previous studies have been confirmed with the exception of the phase Al3+x
Mo1–x
, which has not been detected. The congruent melting point of Al8Mo3 was found at 1546±3°C and the Al-rich phase boundary for AlMo3 has been determined between 800 and 1200°C.
EBSD and EDX analysis at the cladding–substrate interface of a laser clad railway wheel
Authors: Farooq Muhammad Umar , Klement Uta , Nolze Gert 
Published: December 2013

Abstract
Electron backscatter diffraction and energy-dispersive X-ray spectrometry were used to investigate the intermixed interface produced during laser cladding of a Co–Cr–Mo alloy on a steel substrate. A multi-component system and rapid solidification conditions together lead to a complex microstructure at the interface. The solidification of the cladding starts with the formation of an interface layer, which is about 75lm in thickness and consists of randomly oriented equiaxed grains of Co–Cr–Fe solid solution and martensite. Orientation analysis of the grains in the interface layer revealed that some grains have a special orientation relationship with the former austenite grains in the heat affected zone but the cladding is not formed by epitaxial growth on the substrate. Intermixing of the materials at the interface is providing a strong bond between the substrate and the cladding. For a grain from the interface layer to emerge as columnar grain in the cladding, it was determined that its <001> crystallographic direction is not supposed to deviate more than 25° from the sample normal direction.
Thermodynamic properties of liquid silver–indium–antimony alloys determined from e.m.f. measurements
Authors: Jendrzejczyk Dominika , Gierlotka Wojciech , Fitzner Krzysztof 
Published: December 2013

Abstract
The thermodynamic properties of liquid Ag–Sb–In alloys were determined using solid oxide galvanic cells with zirconia electrolyte. The following galvanic cells were employed:

(I)

Re
+
kanthal,

Ag
x

−

Sb

(

1
−
x
−
y

)

,

In
2

O
3

/
/

ZrO
2

+

(

Y
2

O
3

)

/
/
Ni
O
,
Ni
,

Pt

in the temperature range from 973 to 1200K.
Thermodynamic properties of the liquid phase were described by the Redlich–Kister–Muggianu formula and the phase relations in the ternary system were calculated. The results of the calculations were compared with experimental data available from different literature sources.
Microstructure of the “white layer” formed on nitrided Fe-7wt.% Cr alloys
Authors: Hosmani Santosh S. , Schacherl Ralf E. , Mittemeijer Eric J. 
Published: December 2013

Abstract
The formation of a compound, “white” layer on the surface of Fe-7wt.% Cr alloy, by exposure to a gas mixture of ammonia and hydrogen at 580°C, was investigated. The microstructure of the surface layer was analysed employing light and scanning electron microscopy, X-ray diffraction and electron probe microanalysis. For the first time a quantitative (phase) analysis of such a white layer was carried out, demonstrating the presence of a dispersed CrN phase within a γ| iron-nitride matrix.
The effect of ageing on tensile behaviour, mode I and mixed mode I/III fracture toughness of 7010 aluminium alloy
Authors: Eswar Raju K. S. S. , Mukhopadhyay Ashim K. , Kamat Samir V. 
Published: December 2013

Abstract
The effect of ageing on the tensile behaviour, mode I fracture toughness and mixed mode I/III fracture toughness of 7010 aluminium alloy plate was investigated. It was found that the 0.2% proof stress in this alloy increased from the under-aged temper to the peak-aged (T6) temper and then subsequently decreased in the over-aged (T73) temper. On the other hand, the ductility exhibited a monotonic decrease from the under-aged temper to the over-aged temper. The Ludwigson equation was found to best describe the flow behaviour in all the three ageing tempers. Under mode I as well as mixed mode I/III loading, the highest fracture toughness was seen in the under-aged temper, whereas the fracture toughness values in the peak-aged and over-aged tempers were comparable.
Plane bending fatigue behavior of interstitial-free steel at room temperature
Authors: Islam Mohammed Aminul , Tomota Yo 
Published: December 2013

Abstract
Interstitial-free steels are widely used as thin sheet for automobile external panels. For this type of application, essential properties of the steel are deep-drawability and stretch-formability. However, low-strength interstitial-free steel is nearly pure iron and work on fatigue fracture behavior of this steel might be adopted as a basic study to understand the behavior of high-strength steels used for structural components. In this study, the fatigue fracture behavior of low-strength interstitial-free steel has been studied at room temperature in air and in an argon atmosphere. Fractographic observations on fatigue fracture surfaces reveal a mixed type of fracture mode (intergranular and transgranular cracking) for all specimens. The major portion of intergranular fracture has been found at the regions of low and medium crack lengths. Further increase in the crack length causes a decrease in the proportion of intergranular cracking and, finally, the fracture mode becomes completely transgranular. At the same test temperature, the proportion of intergranular fracture drastically decreased when the test was carried out in the argon atmosphere.
Influence of process parameters on particle characteristics using a combined pressure-swirl-gas atomizer
Authors: Achelis Lydia , Uhlenwinkel Volker , Bauckhage Klaus 
Published: December 2013

Abstract
This paper summarizes the latest results in the development of a combined pressure-swirl-gas atomizer. The main goals of this investigation are to characterize the generated metal powders in terms of spray pattern and particle size distribution. With the combined pressure-swirl-gas atomizer it is possible to create 150kgh−1 of tin powder with mass medians between 30 and 110lm (tin alloys) and geometric standard deviations below 1.9 with a nitrogen consumption of 100kgh−1. Gas flow and melt mass flow can be varied independently of each other, while their characteristic ratio of mass flows can be held below 0.7, which opens new potential for low gas consumption in gas atomization. The experiments were conducted with water and tin melts as model fluids. The comparison of the dimensionless numbers shows that the model experiments are comparable and basically extendable to other melts as long as the material characteristics allow this.
Synthesis and oxidation of Zr3Al3C5 powders
Authors: He L. F. , Zhou Y. C. , Bao Y. W. , Wang J. Y. , Li M. S. 
Published: December 2013

Abstract
Predominantly single phase Zr3Al3C5 powders were synthesized in an Ar atmosphere using Zr – Al intermetallics and graphite as starting materials. The reaction path of Zr3Al3C5 synthesis was discussed based on differential scanning calorimetry and X-ray diffraction results. Lattice parameters of Zr3Al3C5 determined using the Rietveld method are a = 3.347 Å and c = 27.642 Å. In addition, the oxidation of Zr3Al3C5 powders was tested by using thermogravimetry – differential scanning calorimetry. The starting and complete oxidation temperatures are 400 °C and 1200 °C, respectively. These temperatures are much higher than those for ZrC, suggesting that Zr3Al3C5 has better oxidation resistance than ZrC. On the other hand, the oxidation degree of Zr3Al3C5, defined for the complete carbide – oxide transformation, overshot 100 % during oxidation. This overshooting is attributed to the formation of amorphous carbon. The phase evolution during the oxidation of Zr3Al3C5 was also investigated.
Infrared spectroscopy and X-ray diffraction data of In – Se compounds
Authors: Vassilev Gueorgui P. 
Published: December 2013

Abstract
The aim of the present work is to contribute to the identification of indium – selenium phases. Infrared absorption spectra were obtained from some indium – selenium compounds (In4Se3, InSe, In6Se7, α-In2Se3). X-ray diffractograms of the recently found phase In9Se11 and of InSe are also reported. Both kinds of data can be used for identification of the respective compounds.
It is confirmed that α-In2Se3 is stable at room temperature. The stability of the hexagonal InSe modification is also proved and its lattice parameters are recalculated.
Formation of δ-Al2O3 hollow nanoparticles via a chemical vapor condensation process
Authors: Lee Chang-Woo , Lee Jai-Sung 
Published: December 2013

Abstract
Aluminium oxide nanoparticles were synthesized by a chemical vapor condensation process using aluminium acetylacetonate as a precursor in the temperature range of 700 – 1000 °C. From X-ray diffraction results, it was found that the δ-Al2O3 phase was obtained at 900 °C and 1000 °C. Transmission electron microscopy observation revealed that δ-Al2O3 nanoparticles 10 – 15 nm in diameter consisted of a hollow structure with shells 2 – 3 nm in thickness. The sequential decomposition of acetylacetonate groups observed in thermogravimetry analysis showed that the formation of a hollow structure depends on the characteristics of the metal – organic precursor. Also, a decrease in the transmittance of δ-Al2O3 nanoparticles was found in the wavelength range of 300 – 900 nm by UV-Visible spectrophotometry, which is expected to occur by scattering and absorption of light depending on particle size and hollow structure.
Thermomechanical processing of AA6061 billets for semi-solid forming
Authors: Birol Yucel 
Published: December 2013

Abstract
Extruded bars of AA6061 alloy were heat treated above the solidus temperature to produce wrought aluminium feedstock for thixoforming. The extruded material recrystallized during heating to the semi-solid state, producing nearly equiaxed polygonal grains with high-angle boundaries. Melting started at triple junctions during subsequent isothermal heating and progressed along grain boundaries. The low melting point eutectic phase and the high-angle grain boundaries introduced by recrystallization both promoted the grain boundary melting process. The desired feedstock characteristics, comprising complete grain boundary wetting, a perfectly cylindrical slug shape and an average grain size below 100 microns were obtained after 5 min at 640 °C and 635 °C for extrusion ratios of 14: 1 and 5: 1, respectively.
Cyclic deformation behaviour and lifetime calculation of the magnesium die-cast alloys AZ91D, MRI 153M and MRI 230D
Authors: Ebel-Wolf Barbara , Walther Frank , Eifler Dietmar 
Published: December 2013

Abstract
The magnesium alloys AZ91D, MRI 153M and MRI 230D were investigated in the form of die-cast specimens with a cast-skin. The fine-grained microstructure consists of a dendritic magnesium solid solution and interdentritic precipitates. The cyclic deformation behaviour was characterised in stress-controlled load increase and single step tests by means of mechanical stress – strain hysteresis and temperature measurements. Load increase tests allow a reliable short-time estimation of the endurance limit. With the physically based lifetime calculation method “PHYBAL”, the lifetime of the magnesium alloys can be precisely calculated on the basis of the plastic strain amplitude and the change of the specimen temperature due to cyclic plastic deformation with three experiments. Lifetimes calculated according to “PHYBAL” agree excellently with experimentally determined data.
Identification of liquid/solid transformations in eutectic Pb–Sn alloy
Authors: Brunčko M. , Kneissl A. C. , Kosec B. , Lojen G. , Anžel I. 
Published: December 2013

Abstract
In this paper the applicability and the efficiency of in-situ electrical resistance measurements with a four-probe method for monitoring the solidification process are presented. For this purpose a special measurement cell was developed. It enables simultaneous in-situ electrical resistance and temperature measurements during solidification to characterize the L → S phase transformation of metals and alloys. The method was experimentally demonstrated with a eutectic Pb – Sn (i. e. Pb-61.9 wt.% Sn) alloy. Additionally, the L → S phase transformation was monitored and compared with conventional differential thermoanalysis. The results of our investigation show that the simultaneous in-situ electrical resistance and temperature measurement method is able to determine the exact position of the start and end points of the L → S phase transformations from the resistance curves R(t) and the corresponding temperatures.
Comparison of the plastic strain distribution during equal-channel angular pressing (ECAP) using 2D and 3D FEM modeling
Authors: Zhernakov V. S. , Budilov I. N. , Alexandrov I. V. , Beyerlein I. J. 
Published: December 2013

Abstract
The plastic flow of a copper billet calculated using 2D and 3D finite element modeling are compared during a single extrusion of equal-channel angular pressing. Both models predict deformation heterogeneity irrespective of material behavior, die geometry and friction conditions. On the symmetry plane where the numerical approaches can be compared, their strain distributions differ, especially as the processing conditions deviate from the ideal conditions. Overall the three-dimensional finite element model calculates lower plastic strains than the two-dimensional model.
Fabrication of high strength nanostructured aluminium alloys by hydrostatic extrusion
Authors: Lewandowska Małgorzata , Pachla Wacław , Kurzydłowski Krzysztof J. 
Published: December 2013

Abstract
In the present work, the possibility of obtaining high strength nanostructured aluminium alloys by hydrostatic extrusion has been shown. Billets of 2017 aluminium alloy were subjected to hydrostatic extrusion either immediately after water quenching or after subsequent ageing. The results have shown that processing by hydrostatic extrusion offers a possibility of grain refinement down to the nanometre scale in the age-hardenable aluminium alloy. However, the effectiveness of the process depends on its initial microstructure. The most promising results are obtained if the alloy is deformed in the as-quenched condition. The hydrostatically extruded aluminium alloy exhibits very high tensile strength with reasonable ductility. The stability of mechanical properties over a wide range of temperatures (from cryogenic to well above the ambient) is discussed. The results obtained are compared to similar 2XXX aluminium alloys processed by other severe plastic deformation methods.
Effect of V2O5 doping on the microstructure and local composition of textured Sr0.4Ba0.6Nb2O6 ceramics
Authors: Wang Xian-Hao , Gu Hui , Huang Qing-Wei , You Li-Ping 
Published: December 2013

Abstract
A comparison of phases and the microstructures of textured Sr0.4Ba0.6Nb2O6 ceramics without and with V2O5 addition was carried out using transmission and analytical electron microscopy. The dopant was not found in Sr0.4Ba0.6Nb2O6 grains but in the inter-granular regions, including both grain boundary and second phase. Grain boundaries in the sample without V2O5 are clean, but those in the V2O5-doped sample exhibit a variety of structures, with and without an amorphous film of variable thickness. In general the vanadium excess follows the same trend of film width, while the Sr excess is generally negative and the Ba excess is positive, suggesting that the amorphous films at grain boundaries are rich in V and Ba and deficient in Nb and Sr. The second phase was determined as Ba3V4O13 phase containing small amounts of Sr and Nb. Such V- and Ba-rich inter-granular liquids promoted the densification and texturing, and affected the dielectric constant at low frequency but not the Curie temperature.
Development of SMD 32.768 kHz tuning fork type crystals
Authors: Lee Sungkyu , Moon Yangho , Seo Won-Seon , Ahn Jae-Hwan , Chung Hyungsik 
Published: December 2013

Abstract
Taguchi's design of experiment method and statistical F-test were used to further optimize design parameters for as-fabricated resonance frequency of tuning forks for use in Qualcomm® mobile station modem (MSM)-3000TM series central processing unit chips of code division multiple access, personal communication system, and global system for mobile communication systems. After much trial and error, finite element method modeling and Taguchi's design of experiment method enabled selection of essential design parameters to effectively manufacture tuning fork test samples using photolithography with subsequent photoresist spray coating. As-fabricated resonance frequency values of a tuning fork blank thus manufactured remain almost the same prior to final frequency adjustment of the mounted crystals, regardless of pressure change from ambient to the designated packaging pressure of 6 × 10−5 Torr. The tuning fork test samples thus fabricated were characterized and analyzed using Taguchi's design of experiment method and statistical F-test to evaluate the sensitivity of as-fabricated resonance frequency for various design parameters fror ambient to the designated packaging pressure of 6 × 10−5 Torr. As-fabricated resonance frequency is most sensitive to tine width (x) and variance analysis results showed that only x and y (tine length) are significant design parameters and no design parameter significantly affects the as-fabricated resonance frequency change with the vacuum level of the package: the as-fabricated resonance frequency change with vacuum level turned out to be independent of design parameter contributions.
Fatigue strength and fracture behavior of steels with and without interstitial carbon at room temperature in air
Authors: Islam Mohammed Aminul , Tomota Yo 
Published: December 2013

Abstract
In this study, fatigue performance and fracture behavior of interstitial-free, low carbon and phosphorus-added low carbon steels have been investigated by plane bending fatigue tests at room temperature in air. For all steels, fatigue tests were carried out at a frequency of 1000 cycles per minute, however, a limited number of specimens of low carbon steel were also tested at frequencies of 500 and 1500 cycles per minute. After all mechanical tests, fracture surfaces were cut and examined using scanning electron microscopy to identify the fracture features. At any applied stress level, low carbon steel showed better fatigue performance than interstitial-free steel, and phosphorus addition further improved the fatigue life of low carbon steel. Fractographic observations on fatigue fracture surfaces revealed transgranular fracture for low carbon steel and intergranular fracture for interstitial-free steel. Interestingly, addition of 0.12 wt.% of phosphorus in low carbon steel could not change the dominant transgranular fracture behavior of the steel.
Grain refinement response during twist extrusion of an Al-0.13% Mg alloy
Authors: Berta Marco , Orlov Dmitry , Prangnell Philip B. 
Published: December 2013

Abstract
Twist extrusion is a recently developed method of severe plastic deformation that principally uses torsion to generate high strains in a repeatedly extruded billet, while maintaining a constant cross-section. The method thus results in a deformation gradient across the billet section. To date, the grain refinement behaviour of alloys deformed by twist extrusion have only been investigated qualitatively. In this study high resolution electron backscattered diffraction has been used to quantify the deformation structures produced by twist extrusion, in a model, single-phase, Al-0.13 % Mg alloy, with the aim of investigating the potential of the technique for producing ultra-fine grained metals, as well as the homogeneity of the microstructure and strain distribution in processed billets.
The effect of grain size on strain rate sensitivity and activation volume – from nano to ufg nickel
Authors: Vehoff Horst , Lemaire Delphine , Schüler Kerstin , Waschkies Thomas , Yang Bo 
Published: December 2013

Abstract
The strain rate sensitivity of nanocrystalline nickel was studied at different temperatures in tensile tests and with a nanoindenter in order to examine the effect of grain size on the different deformation mechanisms of nanocrystalline materials. The experiments yielded, depending on temperature and strain rate, the strain rate sensitivity, the activation volume and the creep exponents as a function of stress and grain size. From the creep experiments the transition between grain boundary sliding and dislocation climb as a function of temperature was obtained. The strain rate jump tests gave extremely small activation volumes, nearly a factor of 100 smaller than in conventional nickel as a function of grain size. To help in understanding this behaviour the strain rate sensitivity of single grains was tested with a nanoindenter. The results clearly showed that the primary interaction of dislocations with grain boundaries is the reason for the strong rate effects and small activation volumes observed.