bluuebunny/crossref_metadata_2025 huggingface dataset:
Mechatronic Correctional Devices for Precision Engineering
Authors: Bansevičius Ramutis , Giniotis V.
Published: March 2009

The paper deals with mechatronic devices for accuracy improvement of measuring and metal cutting machines, robots, etc. The mechatronic means for correction of systematic errors of information-measuring systems including linear and rotary encoders and final 3-D position correction of a cutting instrument or touch probe are presented. The technical solutions are given with the application of active materials for smart probes and piezoactuators. A case for the application of piezoactive raster plates and other elements is described together with volumetric control diagrams and examples of practical implementation. Error correction problems can be solved using the piezoactive, piezoelectric or piezomagnetic substrate in the measuring or the datum system of the machines. An implementation of piezoelectrical correctional devices is very efficient for precise engineering where cutting or measuring forces are negligible and displacement values are in the range of several micrometers.
Investigation into Influences of Visual Apparatus Sensor and Executor Characteristics on the Quality of Information Transmission to Sensory Organs
Authors: Mariūnas Mečislovas , Šešok A.
Published: March 2009

Analysis into the effects of parametric characteristics of visual aid on the perception level
of information transmitted has led to the possibility of examining and determining the quality of the
reading level as a function of certain parameters of a digital apparatus (sensor), the distance to the
text, the size of letters and the intensity of light. Efforts have been made to evaluate the effect of the
specifications of the executor as well as the information transfer (by tactile way) speed onto the
sensory organs of the disabled person at the perception level. A choice has been made of rational
information transfer speeds and appropriate visual aid characteristics to facilitate an adequate
perception level.
Measurement Techniques of a European Sea Level Service Site in KLAIPEDA
Authors: Parseliunas E. , Viskontas P. , Grigas M. , Obuchovski R. , Marozas L.
Published: March 2009

The technical equipment including hardware and software of European Sea Level Service
(ESEAS) station KLAIPEDA (KLPD) is presented in the paper. The tide gauge Klaipeda (previous
name – Memel) was established in 1811 in the east part of the Baltic Sea, at the estuaries of
Curonian Lagoon. KLAIPEDA ID number at the Permanent Service of Mean Sea Level (PSMSL)
is 080161. Upgrading of the station is done according to the ESEAS-RI project (Contract No
EVR1-CT-2002-40025). KLPD site was equipped with a digital float tide gauge, sea-water
conductivity sensor, air temperature, pressure and humidity sensors, wind speed and direction
sensor and GPS receiver with antenna. The four characters ID KLPD and IERS DOMES number
10802M001 was assigned to the permanent GPS station KLAIPEDA. Tide gauge KLAIPEDA was
certified as ESEAS Operational Site in 2003. It provides near real time (hourly) data to
corresponding data servers. The data warehouse system is built on Gentoo Linux, with Apache2,
MySQL 4.0.22 and PHP 4.3.9. The communication structure and software applications are also
presented in the paper.
Research of Accuracy Parameters of the Gantry Course
Authors: Viselga Gintas
Published: March 2009

A laser instrument maintains the course of the positioned gantry module. A laser beam
generator emitting a vertical beam is placed at the end of the experimental field. A laser beam
catcher with photo diodes is mounted onto a positioned gantry module replaceable support. Course
deviations were assessed in two cases: when laser, straight-course maintaining mechanism was
mounted at the same end of the spar as positioning trundle; and when it was mounted at the middle
of the spar. Furthermore, we estimated how course deviations vary when changing the interaxial
distance of laser catcher photodiodes.
An electromechanical transmitter was used in the tests. The gantry module is positioned by a
special positioning trundle and is run by a 12 V electric motor through a worm self - braking
reduction gear.
Electrochromic Glazings for Window Applications
Authors: Vondrák Jiŕí , Sedlaříková Marie , Vlček Milan , Mohelníková Jitka , Macalík Michal
Published: March 2009

Electrochromic materials have found practical applications in special devices such as:
- systems with controlled transmission (surfaces with regulated radiation-electrochromic glazings),
- systems with controlled reflection (electrochromic mirrors with regulated solar reflectance), and
- systems with change of color contrast (special electrochromic information displays).
This paper deals with electrochromic devices with a controlled transmission. Electrochromic
glazings can be described as devices based on electrochromic materials that operate as reversible
switching solar control shutters. These special glasses have found application not only for window
glazing in hot climatic conditions but they are also recommended for buildings with large glazed
shells where overheating and glare effect represent serious problem for daily service and operation.
Dispersion and Absorption in Media with Stretch Exponential and Fractional Power Relaxation
Authors: Miškinis Paulius
Published: March 2009

Dispersion and absorption in a media with stretch exponential or Kohlrausch–Williams– Watts relaxation are considered. The frequency-dependent dispersion and absorption coefficients, phase and group velocities are obtained and compared to Debye–Mandelshtam– Leontovich expressions.
Phase Investigations of Copper Based CuZn38Al2MnFe Alloy
Authors: Szkodo Marek , Głowacka M. , Smajdor M. , Bugłacki Henryk
Published: March 2009

In the work phase investigations of special brass CuZn38Al2MnFe alloy are presented.
The microstructure, chemical composition and phase identification of the investigated alloy were
examined using scanning electron microscopy (Philips 30/ESEM), light microscopy Leica coupled
with PC computer with installed MultiScan program, energy dispersive X-ray spectroscopy (EDX)
and X-ray diffractometry (XRD), respectively. The investigation of volume fraction existing phases
was carried out using image analysis. It was found in the test bend that presence of Fe4Mn77Si19
phase in microstructure caused an increase of brittleness of the tested alloy.
Critical Slip in Maximum Electromagnetic Power of a Motor for Borehole Prospecting Mechatronic Devices
Authors: Gečys S. , Gudžius S. , Markevičius L. , Morkvėnas A.
Published: March 2009

The extraordinary conditions for borehole motors such as: wide operating medium
temperature change interval from –20oC up to +250oC, hydrostatic pressure changes from
atmospheric up to 210 MPa, operating medium – dielectric liquid, limited power source, long
geophysical, cable of up to 10,000 m non-constant load, due to the operating cycle have influence
on their reliable operating, maximum power transmission, and change of characteristics. In this
particular case, it is important to know the maximum electromagnetic power, which may be created
by the motor. The critical slip and maximum electromagnetic power of the induction motor with a
solid rotor supplied from a limited power-source and through the complex circuit, taking into
account the parameters of the motor and supply circuit, as well as the operating peculiarities, have
been derived. The study of computed characteristics of the borehole motor, taking into account the
above-mentioned conditions, show that the motor supplied from a limited power-supply source and
through the complex circuit should be investigated inseparably from the whole system.
The Mechatronics Design for Measuring Fluid Friction Losses in Pipe Flows
Authors: Gürbüz Riza
Published: March 2009

The purpose of this article is to design a mechatronics system to measure fluid friction
losses in a specially designed fluid friction apparatus. It measured fluid flow rates by using venturi
tube and orifice plate, and velocity of fluid is calculated in terms of flow rate and pipe diameter.
Friction factor (K factor) of some valves and fittings such as tee, elbow, Y Junction, gate and globe
valves and friction losses in pipe was measured in this system. It is one of the best methods to
measure losses in pipes and fittings experimentally.
It used a computer, data acquisition cards, pressure differential transmitters, venturi tube and
orifice meter to measure the flow rate, pressure drops on flow rate measurement devices and
pressure drops of some valves and fittings to be measured K factors. It also measured the
temperature of fluid by using J type Thermocouple.
A computer program is written to calculate the Reynold number of fluid, friction factor of pipe,
velocity of fluid, frictional losses of fluid, flow rate and K factor of valves and fittings. Required
data was received from measured quantities. The conclusion of experiments is shown in article.
Volumetric flow rate range was determined 0-1 (L/s), while the pressure drop was 0-100 kPa in
experiments.
Improvement and Evaluation of the Study Process in Mechatronic Systems
Authors: Toločka Eligijus , Jančiauskas Bronius , Staškevičius Juozapas Audvydas
Published: March 2009

This article analyses a Mechatronic Systems` (MS) study process connected with the more correspondent preparation process of engineering professionals in the faculty of Mechanics at Vilnius Gediminas Technical University. The analysis and study highlighted aspects of the study process development and its implementation that would enable one at the same rate to prepare more qualified engineers. The authors suggest improving the MS study process for aspects of` practical implementation. Realization of this improvement also requires an appropriate development of the evaluation of the study process and its effectiveness. And this is also what the authors present in the article. Suggested improvement would not only help to develop contemporary MS studies but it could also be applied for the development of studies in other science areas.
Hybrid Experimental – Numerical Full-Field Displacement Evaluation for Characterization of Micro-Scale Components of Mechatronic Systems
Authors: Ostaševičius Vytautas , Gitis Norm , Palevicius Arvydas , Ragulskis Minvydas , Tamulevičius Sigitas
Published: March 2009

Hybrid experimental – numerical techniques are applied to the problem of the interpretation of patterns of fringes that are generated by non-contact full-field experimental methods applied for analysis of dynamic displacement fields of MEMS components. It is shown that even rather simple cantilever beam of a MEMS switch can exhibit complex dynamical response due to the nonlinearities of interactions and the surrounding noise. In many instances the interpretation of experimental results is possible only after numerical simulation of MEMS components in virtual computational environments.
Optimal Design and Analysis of UAV Swan Fuselage
Authors: Leomar Priit , Tamre Mart , Riibe Tõnis , Vaher Tõnu , Haggi Toomas
Published: March 2009

Eli Ltd. and Tallinn University of Technology (TUT) Department of Mechatronics are
currently performing studies in order to develop a mini-class universal purpose unmanned aircraft
[1,2]. The paper focuses on strength calculations and weight vs. strength optimization of the
fuselage of this developed UAV system. To develop a strong but lightweight UAV fuselage,
advanced computer modeling and finite element structure analysis are used as virtual prototyping
tools for the optimization of the fuselage at early design stage and through the production period to
improve the design [3]. Design optimization is applied to minimize the maximum stresses within
the fuselage, subject to strain constraint in conjunction with both geometry and choice of
appropriate fibre orientations and stacking sequence as design variables and also material
parameters. The fuselage for the UAV plane was designed and manufactured using E-Glass/Epoxy
and High modulus (HM) carbon/Epoxy composites. In this paper ANSYS software has been
successfully applied to minimize the weight of the fuselage and increase the UAV fuselage strength.
The results show how the fuselage design could be improved with the help of finite element method
analysis and provide guidelines for the structure and material design for the composite based UAV
SWAN fuselage.
Analysis of the Possibilities of the Usage of Electrical Synchronous Link for a CNC Gear Hobbing Machine
Authors: Slivinskas Kastytis , Gičan V. , Poska A.J. , Augustaitis Vytautas Kazimieras
Published: March 2009

The method of creating the dynamical model of the CNC gear hobbing machine and for
its analyzing is presented in this paper. The model comprises detail mechanical parts of the hob
spindle and work spindle axes, their electrical counterparts, linking, and allows one to investigate
dynamic characteristics of the machine and to simulate processes, which take place during gear
hobbing. The article also presents the simulation diagram, introducing these axes and the third axis,
which help to model the cutting process. It also presents results of simulation of processes during
hobbing and amplitude-frequency characteristics calculated.
Microstructural Refinement under High Plastic Strain Rates during Hydrostatic Extrusion
Authors: Kurzydlowski Krzysztof Jan , Richert Maria W. , Leszczyńska B. , Garbacz Halina , Pachla Wacław
Published: March 2009

High strain rates have a similar influence to large deformations on the refinement of microstructure. In both cases, at large strains and high deformation rates, a strong tendency to form microbands is observed. It was found, that the width of the microbands is very sensitive to changes of the deformation parameters. It has been observed particularly, that in severely deformed materials, the width of the microbands is reduced to nanometric dimensions. Hydrostatic extrusion, which has been used in for the deformation of copper in the current work, strain rates exceeding 2 1 3.84 10 − ⋅ ε = × s were employed. In all the samples investigated, numerous microbands were found in the microstructure. The width of microbands varied from 20 to about 400 nm. Thus, the width of some of the microbands exhibited dimensions typical of nanometric materials. Additionally, a special feature was the appearance of large areas of subgrains with an average dimension of about 200 nm. These areas were identified as recrystallized dynamically, or post-dynamically. Large misorientations were found between the microbands and the surrounding “matrix’. Such misorientation facilitates the formation of high angle boundaries, which in turn contribute to the changes of microstructure and mechanical properties. The mechanism for the creation of high misorientation in the microband areas is probably different from that operating during the process of dynamic recrystalization. The results confirm the possibility of obtaining a nanometric structure at lower deformation, but at higher strain rates.
Deformation-Induced Nanocrystallization in Al-Rich Metallic Glasses
Authors: Boucharat Nancy , Hebert Rainer J. , Rösner Harald , Wilde Gerhard
Published: March 2009

Deformation-induced nanocrystallization has been investigated in a marginally Al88Y7Fe5 glass forming alloy. Conventional calorimetry and microstructural analyses of materials that have been subjected to high pressure torsion straining (HPT) at room temperature indicate the development of an extremely high number density of small Al nanocrystals. The nanocrystals appear to be distributed homogeneously throughout the sample without any evidence of strong coarsening. Moreover, the comparison between nanocrystallization caused by the application of either HPT, cold-rolling or in-situ TEM tensile straining yielded the identification of the probable mechanisms underlying the formation of nanocrystals. These results form the basis for the development of advanced processing strategies for producing new nanostructures with high nanocrystal number densities which allow increased stability and improved performance.
The Effect of Dispersoids and Processing Variables on Grain Refinement of Aluminium Alloys Deformed by ECAE
Authors: Berta M. , Prangnell Philip B.
Published: March 2009

The effect of fine, non-shearable, dispersoids on the grain refinement of aluminium
alloys, severely deformed by ECAE, has been studied using a model Al-0.2%Sc alloy, during
deformation by Routes A and BC (+90degrees rotation) using a 120°, or 90°, die. The
microstructure in the dispersoid-containing alloy was compared to a single-phase alloy using high
resolution EBSD analysis. With Route A the presence of fine dispersoids was found to
significantly retard the development of new high-angle grain boundaries and the formation of a fine
grain structure, by homogenising slip and inhibiting microshear bands. This difference was greatly
enhanced, using Route BC. Similar results were obtained with the two die angles, but with Route A
refinement tended to be slightly less effective when using the 90° die.
Evolution of Precipitate Coarsening Reaction in a Nanostructured Fe-Ni-Mn Maraging Alloy
Authors: Hossein Nedjad S. , Nili-Ahmadabadi Mahmoud , Furuhara Tadashi , Maki Tadashi
Published: March 2009

Fe-Ni-Mn maraging alloys show discontinuous coarsening of fct θ-NiMn precipitates along prior austenite grain boundaries (PAGBs) during isothermal aging. Heavy cold rolling of a solution annealed Fe-10Ni-7Mn (wt. %) maraging alloy and subsequent aging treatment at 773 K led to the formation of a nanostructured material. Hardness measurement and transmission electron microscopy were used to study the aging behaviour and microstructural evolution of the nanostructured alloy. At the early stage of aging, an ultrafine grained structure was observed with fine matrix precipitates. However, at later stages of aging, severe coarsening of precipitates was found. At that stage, a lamellar microstructure composed of finely precipitated ferrite laths and ultrafine ferrite grains were identified. Coarse fct θ-NiMn precipitates were identified at the ultrafine ferritic grain boundaries. Development of the coarsening reaction was found to increase the ultrafine grained ferritic regions with prolonged aging.
SPD Processed Alloys as Efficient Vacancy-Hydrogen Systems
Authors: Wieczorek Arkadiusz K. , Krystian Maciej , Zehetbauer Michael
Published: March 2009

Nanocrystallization is known to yield several improvements for the storage and uptake rate of hydrogen in solids. Usually this process is achieved by ball milling to produce a nanopowders. However, handling of these powders is risky and difficult, and there is also a high risk of introducing impurities into the storage material. In this situation materials processed by Severe Plastic Deformation (SPD) yield several advantages: (i) the materials are produced in bulk shape with 100% density; (ii) the introduction of impurities is minimized, (iii) in addition to additional grain boundaries, many dislocations and particularly vacancies are generated which may further improve the hydrogen storage capacity and kinetics.
The Role of Inclusions in the Corrosion Resistance of Hydrostatically Extruded Steel Products
Authors: Klassek Dominika , Suter Thomas , Schmutz Patrik , Pachla Wacław , Lewandowska Małgorzata , Kurzydlowski Krzysztof Jan , von Trzebiatowski Oliver
Published: March 2009

The corrosion behaviour of 316LVM in NaCl solution steel has been investigated.
Large scale polarization measurements and etching tests in V2A solution showed that the
hydrostatically extruded (HE) 316LVM steel had a lower corrosion resistance than specimens in the
as received condition. Small area measurements were carried out in order to determine the sites that
were responsible for the decreased corrosion resistance of the HE 316LVM steel. Tests on cross
sections parallel to the HE direction, showed better corrosion resistance than on cross sections
perpendicular to the HE direction. These observations indicate, in combination with SEM and
AFM measurements, that the inclusions which were deformed during HE, can trigger the onset of
corrosion on HE 316LVM steel.
The Role of Plastic Deformation in the Process of Powder Sintering
Authors: Milman Yu.V. , Slipenyuk Alexander N.
Published: March 2009

It is generally supposed that diffusion is the main factor controlling the process of
powder sintering. In this work it is shown that plastic deformation achieved by means of
dislocation movement is also an important constituent of the sintering process. Since temperature
essentially affects dislocation mobility, the temperature ranges of cold, warm and hot deformation
are discussed. The stresses occurring on powder sintering leading to plastic deformation of the
material are estimated. On the base of results recommendations are made for selecting the optimal
condition for the sintering of powders.
Fabrication and Micro-Structure Characterization of Al2O3/Ni-P Composites with Interpenetrating Phases
Authors: Michalski J. , Wejrzanowski Tomasz , Gierlotka Stanislaw , Bieliński J. , Konopka K. , Kosmač Tomaž , Kurzydlowski Krzysztof Jan
Published: March 2009

The fabrication of 3D interpenetrating phases in ceramic-metal composites by high
pressure sintering of ceramic powder coated with Ni-P nanoparticles produced by electro-less
chemical plating is reported. Electro-less nickel plating resulted in a nano-metric layer of spherical
Ni-P nanoparticles of approximately 20-50 nm diameter over the entire surface of the ceramic
powder. The coated powders were consolidated by hot pressing (HP) process followed by
pressureless sintering after cold isostatic pressing (CIP). SEM, TEM and XRD methods were used
to investigate the influence of the consolidation temperature and pressure on the microstructure of
composites and particularly the morphology of metallic Ni-P phase. The homogeneity of the
interpenetrating network structure was measured by computer image analysis and compared with
the results of electric resistance measurements. The results indicate that the use of electroless nickel
plating and high pressure consolidation process enables the fabrication of uniform 3D
interpenetrating continuous metal-ceramic composites and controlled-density composites
possessing a metallic phase of nano- or micro-metre size.
Nanocrystalline Cemented Carbides Sintered by the Pulse Plasma Method
Authors: Michalski Andrzej , Siemiaszko D. , Jaroszewicz Jakub , Rosiński Marcin , Psoda M.
Published: March 2009

Nanocrystalline WC-12wt.%Co was consolidated by Pulse Plasma Sintering (PPS) at various temperatures between 900 and 1200oC for 6 minutes under a pressure of 60MPa. Cemented carbides sintered at 1100oC have a relative density of 99%, a hardness of 2248HV30, the fracture toughness, KIC=12.5 MPa*m1/2, and have a structure containing 50nm WC crystallites. Increasing the sintering temperature to 1200oC causes an increase in the size of the WC crystallite size to about 110 nm, reduces the hardness to 2198HV30, and decreases the KIC to 9.7 MPa*m1/2.
Pressure-Assisted Lateral Nanostructuring of the Epitaxial Silicon Layers with SiGe Quantum Wells
Authors: Antonova I.V. , Gulyaev M.B. , Skuratov V.A. , Soots R.A. , Obodnikov V.I. , Misiuk Andrzej , Zaumseil P.
Published: March 2009

Transformations of the SiGe/Si superlattice structures, either annealed at high pressure, or irradiated by high energy ions and subjected to post-implantation annealing, were studied and compared. Both types of treatments were found to lead to the formation of recharged defects clusters, resulting in the appearance of peaks on C-V characteristics, shrinkage of Ge profiles registered by SIMS technique after annealing, and disappearance of peaks in the free carrier profiles. The effects were more pronounced in the case of high energy ion implantation. The results are explained by the vacancy - assisted precipitation of Ge in SiGe layers.
SAXS and XAFS Analysis in Forming of Metal Nanoparticles in Water-in-scCO2 Microemulsions
Authors: Harada Masafumi , Kimura Yoshifumi
Published: March 2009

Metal particles of silver (Ag) and copper (Cu) have been synthesized in the presence of
Aerosol-OT (AOT) or fluorinated surfactants in water-in-scCO2 microemulsions by the chemical
reduction of AgClO4 and Cu(ClO4)2. The formation of Ag particles by the photo-reduction using
UV-light have been confirmed by in-situ UV-Vis, X-ray absorption fine structure (XAFS), and
small angle X-ray scattering (SAXS) measurements. Cu particles have also been prepared by the
addition of a reducing reagent sodium borohydride, and the electronic structure of Cu ionic species
has been investigated after reduction in the water-in-scCO2 microemulsions. The average size of
aggregates of Ag particles in the microemulsions by means of in-situ SAXS measurements also has
been estimated.
Mechanical Properties of Aluminium Processed by ECAP
Authors: Molak Rafal M. , Pakiela Zbigniew
Published: March 2009

The aim of this study was to investigate the influence of large plastic strain on the microstructure and mechanical properties of aluminium processed by severe plastic deformation (SPD) by the Equal Channel Angular Pressing (ECAP) method. Polycrystalline high purity aluminium (99,99%) was pressed at room temperature to produce samples subjected to 4, 8 and 12 ECAP passes. The microstructure of aluminium was examined using a light polarized microscope. Microhardness measurements and tensile tests were undertaken to determine the mechanical properties of the material processed by ECAP. The results obtained show the relationship between the microstructure and the mechanical properties of the material.
Elastic Constants Relaxation in Disordered Heterogeneous Systems
Authors: Turik A.V. , Reznitchenko L.A. , Chernobabov A.I. , Radchenko G.S. , Turik S.A. , Radchenko M.G.
Published: March 2009

Using self-consistent effective-medium theory, we studied the complex elastic compliances of conducting disordered heterogeneous piezoelectric-polymer systems. The considered system is a random mixture of piezoelectric spheroids and polymer ones with the same orientation. The proximate cause of the effective elastic constants frequency dependencies was considered. The nature of the obtained spectra was analyzed.
Memory Effects in Quantum Theory of Relaxation
Authors: Morozov V.G. , Roepke G.
Published: March 2009

We present an approach to theory of relaxation processes with memory in which the time evolution of one-particle distribution functions is coupled with the evolution of many-particle correlations associated with energy balance. The basic idea is to treat the mean interaction energy as an independent state variable in addition to one-particle distribution functions. The method is illustrated by two examples: relaxation in a system with weak pairwise interaction and relaxation in a two-band laser-excited semiconductor.
Specific Features of Brillouin Spectra at a High-Temperature Phase Transition in Cs5H3(SO4)4xnH2O Crystals
Authors: Fedoseev A.I. , Lushnikov S.G. , Ko J.H. , Kojima Seiji , Shuvalov L.A.
Published: March 2009

This paper presents detailed Brillouin light scattering studies of the acoustic response of
a Cs5H3(SO4)4xnH2O (PCHS) crystal in the vicinity of a superionic (superprotonic) structural phase
transition of the first order. Just above the phase transition, splitting of the Brillouin doublet is
observed. The ‘two-mode’ behavior of the longitudinal acoustic phonon can be explained by
coexistence of phases at a structural phase transition of the first order. Above the phase transition,
in the superionic phase, an additional doublet forbidden by the selection rules appears in a narrow
temperature interval. It is concluded that an anomalous behavior of Brillouin light scattering can be
attributed to the influence of dynamically disordered protons on the phonon subsystem.
Zero-Point Drift in Low-Frequency Mechanical Spectroscopy
Authors: Magalas Leszek B. , Piłat A.
Published: March 2009

The concept of the ‘zero-point drift’, ZPD, is introduced and analyzed on the basis of mechanical loss measurements carried out in a low-frequency mechanical spectrometer – inverted torsion pendulum. It is demonstrated that the ZPD, which modifies damped harmonic oscillations leads to false values of the logarithmic decrement computed from several widely accepted algorithms.
Extrinsic Resonance Effects in a Subresonant Mechanical Spectrometer
Authors: Magalas Leszek B.
Published: March 2009

Extrinsic resonance effects observed in a low-frequency subresonant mechanical spectrometer are reported. High resolution of the mechanical spectrometer enables precise measurement of small values of the mechanical loss tangent ( tanϕ = 1- 2 × 10-4) and the apparent high values of the loss tangent detected for extrinsic resonance effects in the vicinity of the eigen frequencies of the spectrometer. Forced oscillations can be used as a ‘signal quality test’ to validate the quality of exponentially damped harmonic oscillations in the resonant mode.
The Snoek Effect in Ternary BCC Alloys. A Review
Authors: Koiwa M. , Numakura Hiroshi
Published: March 2009

The Snoek relaxation is associated with the redistribution of interstitial atoms in the bcc lattice under the application of the oscillatory stress. Addition of substitutional solutes introduces new peaks or broadening of the normal Snoek peak. The experimental and theoretical investigations of the effect are briefly reviewed.
Specific Properties of Industrial High-Damping Fe-Al Steels
Authors: Udovenko V.A. , Chudakov I.B.
Published: March 2009

It is shown that industrial high damping steels based on the Fe-Al metallic system are
characterized by a very high level of internal dissipation of elastic energy. The specific damping
capacity of industrial steels exceeds 40 % and their damping properties are close to those of highpurity
damping alloys based on the Fe-Al system. Mechanical properties of damping steels are
similar to those of conventional construction steels. High level of properties of damping steels can
be explained by their specific crystalline and magnetic structure.
Atomic Structure of the Intercrystalline General Type Boundaries. Mechanisms of the Grain Boundary Peak of Internal Friction. Premelting
Authors: Darinskii B.M. , Kalinin Y. , Sajko D.S.
Published: March 2009

The geometrical classification of the intercrystalline general type boundaries with various misorientations of contacting crystals and orientations of boundary planes was suggested previously. An arbitrary grain boundary breaks up into three families of thermodynamically stable boundaries as a result of fragmentation process due to annealing of polycrystalline sample. Geometrical representations of linear defects (dislocation, steps) and point defects (vacancy, interstitials) in intercrystalline and interphase general type boundaries of different families are developed. Representations about thermal excitations of boundary are developed. Different kinetic processes responsible for intercrystalline sliding, migration are considered, and expressions for characteristics of the low-temperature and high-temperature internal friction grain boundary peaks are obtained. Explanations of internal friction peaks observed near to the so-called ‘grain boundary peak’ are given. Mechanisms of atomic reorganization of grain boundary responsible for the grain boundary phase transitions are also considered. Conditions for the creation of amorphous atomic structure into boundary near to the fusion temperature of a crystal are specified.
Development of Al-15%Si Hypereutectic Alloy Automotive Part by Local Squeeze and Vacuum Diecasting
Authors: Park J.Y. , Kim E.S. , Park Ik Min
Published: March 2009

A functional automotive part, reaction shaft support, was fabricated by local squeeze and
vacuum Diecasting (LSVD) with light-weight Al-15%Si hypereutectic alloy which has good fluidity
and excellent wear resistance. The effects of local squeezing pressure and time-lag of LSVD process
on the microstructure of the product were investigated. Measurement of specific gravity with the
change of local squeeze pressure and time-lag showed that the local squeezing effect can be increased
by increasing squeeze pressure and decreasing time-lag. However, too high a squeeze pressure and
too a low time-lag brought about insufficient squeezing effect due to instant movement to the squeeze
plunger stroke end point. Through the combination of vacuum suction before melt injection and local
squeezing after melt injection in LSVD process, light-weight Al-15%Si alloy reaction shaft support
was successfully developed, resulting in excellent microstructural and mechanical properties
Laser Welding of SSM Cast A356 Aluminium Alloy Processed with CSIR-Rheo Technology
Authors: Akhter R. , Ivanchev L. , Van Rooyen C. , Kazadi P. , Burger H.P.
Published: March 2009

Samples of aluminium alloy A356 were manufactured by Semi Solid Metals HPDC
technology, developed recently in CSIR-Pretoria. They were butt welded in as cast conditions using
an Nd:YAG laser. The base metal and weld microstructure were presented. The effect of different
heat treatments on microstructure and mechanical properties of the welds were investigated. It was
found that the fine dendrite structure of the weld metal contributed for equalizing the mechanical
properties of the joint.
Microstructure Control and Structure Analysis in the Semi-Solid State of Different Feedstock Materials for the Bearing Steel 100Cr6
Authors: Püttgen Wolfgang , Bleck Wolfgang , Hallstedt B. , Uggowitzer Peter J.
Published: March 2009

The bearing steel 100Cr6 in the forged and hardened condition is of great importance in
industrial use. Escaping the geometry restrictions of conventional forging, the application of
semi-solid metalworking (SSM) offers significantly increased design freedom. Using conventionally
available rolled feedstock material with carbide banding, however, results in a higher segregation
tendency during thixoforging, and thus special attention was paid to the feedstock’s “quality”. To
achieve a fine-grained, globular microstructure in the semi-solid state, castings with and without the
addition of 100 ppm titanium were compared with the hot rolled material. With its inherent nitrogen
Ti forms TiN particles, which reduce grain-growth in austenite. The results indicate that TiN
precipitates strongly affect grain growth during solid state processing, but the grain size in the
semi-solid state can only be influenced for short process times. Generally the cast feedstock materials
possess smaller globulites in the semi-solid state compared to forgings, so that a reduction of the
sponge effect and a minimization of the segregation in produced components are expected. Since the
cast material already showed a fine-grained, globulitic microstructure, the use of TiN is not
recommended because of the possible negative influence of TiN on the dynamic mechanical
properties.
Plastic Deformation Characteristics of A356 Alloy with the Variation of Cast Microstructure
Authors: Kwon Yong Nam , Kim Sang Suk , Lee Young Seon , Lee Je Hyun
Published: March 2009

The effect of microstructural features of A356 alloys on plastic deformation behavior was
studied in the present study. To authors' knowledge, the microstructural effect on mechanical
properties of A356 alloy has not been well understood even though this alloy system is one of the
most widely used alloys for the industrial purpose. Specially, quantitative relationship between
properties like ductility and fracture toughness with microstructural features is lacking. In the present
study, four different processing methods were used to investigate how the size and distribution of
primary alpha and eutectic phases influence the plastic deformation characteristics. The prcessing
routes for A356 control arm include low pressure casting, squeeze casting, rheo-casting and
cast-forging processes. Special focus was given to understand which microstructural features do the
beneficial or detrimental effect and how they work.
The Effect of Differential Speed Rolling on Microstructure and Mechanical Properties of an AZ31 Alloy Sheet
Authors: Jeong Ha Guk , Jeong Y.G. , Yoon Duk Jae , Choi Seo Gou , Kim Woo Jin
Published: March 2009

Magnesium alloy AZ31, which processed by conventional rolling or extrusion, has high
anisotropy of mechanical properties in its strength and elongation at room temperature. We compared
the influence of differential speed rolling with conventional rolling process on microstructure and
mechanical properties of commercial AZ31 sheet. Commercial AZ31 alloy sheets were processed
with conventional and differential speed rolled with thickness reduction ratio of 30% at a various
temperature. The elongation of AZ31 alloy, warm-rolled by differential speed rolling is larger than
rolled by conventional rolling. Besides, grain size and distribution on microstructure of the
conventional rolling were coarsely(~30μm) and inhomogeneously but, that those of the differential
speed rolling were fine(~13μm) and homogeneously.
Dynamic Tensile Tests of Auto-Body Steel Sheets with the Variation of Temperature
Authors: Lee Hee Jong , Song Jung Han , Huh Hoon
Published: March 2009

This paper is concerned with the thermo-mechanical behavior of steel sheet for an autobody
including the temperature dependent strain-rate sensitivity. Tensile tests have been carried out
with the high strength steel sheets such as SPRC35R, SPRC45E and TRIP60. The tensile tests were
performed with the variation of the strain-rates from 0.001/s to 200/s and with the variation of
environmental temperatures from -40 to 200. The thermo-mechanical response at the quasi-static
state is obtained with the static tensile test and the one at the intermediate strain-rate is obtained with
the high speed tensile test. Both the strain-rate and the temperature sensitivity of the flow stress are
calculated for the quantitative evaluation of thermo-mechanical behavior of steel sheets. The results
demonstrate that as the strain-rate increases, the variation of the flow stress becomes more dependent
on the temperature. The results also indicate that the material properties of SPRC35R are more
sensitive to the strain-rate and the temperature than those of SPRC45E and TRIP60.
Study on Partial Remelting Microstructures and Mechanical Properties of ZK60-RE Magnesium Alloy
Authors: Shan Wei Wei , Du Zhi Ming , Luo Shou Jing
Published: March 2009

ZK60-RE is a kind of high strength magnesium alloy. Here, starting materials are casting
ZK60-RE magnesium alloy and ZK60-RE magnesium alloy extruded by equal channel angular
extrusion (ECAE), reheating to semi-solid state and studied on their partial remelting
microstructures by means of microscope. The results show that ZK60-RE magnesium alloy
extruded by ECAE are much finer and lead to the formation of spheroids quite rapidly while RE
elements modified casting need a little longer time. At the same time, the mechanical properties of
two kinds of ZK60-RE magnesium alloys are given. To do that, we want to find better magnesium
alloys with high mechanical properties and good thixotropy, which adapt to semi-solid process to
form the high quality complex component one time.
Fiber Reinforced Light Metal Composites by Thixoforging of Thermally Sprayed Prepregs
Authors: Gadow Rainer , von Niessen Konstantin , Unseld Peter
Published: March 2009

New manufacturing methods for metal matrix composites (MMC) are developed.
Thermally sprayed metal coatings on reinforcement-fabrics are used as preforms (prepregs) for an
advanced thixoforging process. The semi-solid forming and simultaneous infiltration in short cycle
times offer the possibility to realize complex near net-shape geometries and reduces fiber damage to a
minimum.
Semisolid Roll Casting of Aluminum Alloy Strip and Its Properties
Authors: Nakamura Ryoji , Inui Hideki , Watari Hisaki , Kumai Shinji
Published: March 2009

A356 was cast into the strip by the semisolid strip casting using an unequal diameter twin
roll caster. This process was one of the rheocasting. The semisolid slurry was made by a cooling slope.
Solid fraction was about 5%. The casting speed was 20 m/min, and the thickness was 4.4 mm. The
as-cast strip could be cold rolled down to 1 mm. The result of tension test of 1mm-thickness-T4
heat-treated strip was as below. Tensile stress was 223 MPa, 0.2 proof stress was 123 MPa and
elongation was 21.8%. Deep drawing could be operated to 1 mm-thickness T4 sheet, and L.D.R was
attained to 2.0. In some condition, 180 degrees bending could be operated without crack at outer
surface. These results mean that semisolid roll cast A356 strip may be able to use for press forming.
Structural Process: Efficient Manufacture of Ductile and Weldable Die Cast Aluminum Components
Authors: Fuchs Marc
Published: March 2009

Bühler has developed an economical way to produce high quality structural parts using
conventional die casting equipment.
Effect of Solid Fraction on Microstructure and Casting Faults of AZ91D Alloys in New Type Semi-Solid Injection Process
Authors: Miwa Kenji , Rachmat Rudi S. , Tamura Takuya
Published: March 2009

We have developed new type semi-solid injection process, that is, runner-less injection
process. In order to investigate the effects of solid fraction on microstructure and casting defects of
AZ91D in new type semi solid injection process, semi-solid forming testing machine which has the
same system as a runner-less injection machine has been made on an experimental basis. Its
temperature controlling system has been established to obtain the homogeneous solid-liquid
coexisted state in its injection cylinder. AZ91D billets are injected into a permanent mold by this
machine in the semi-solid state. A shearing in the part of nozzle of injection cylinder is the most
important to reveal thixotropic property of alloy slurry in semi solid forming process by injection
machine. So it needs controlling of solid fraction to affect thixotropic property. In order to decrease
casting defects and hold homogeneous structure, solid fraction more over 50% is needed. But when
the solid fraction increases more than 50%, primary solid particles grow coarser, and then
controlling method is required to suppress coarsening. In the case of less than 50% of solid fraction,
liquid part preferentially fills inside the permanent mold and alloy slurry continue to fill the mold
behind alloy liquid. Then large casting defects form at the boundary of both flows.
Optimization of Heat Treatment Cycles for Automotive Parts Produced by Rheocasting Process
Authors: Rosso Mario , Grande Marco Actis
Published: March 2009

This work aims at studying the possibility of optimising the heat treatment cycles of parts
produced using the New Rheocasting process in order to reduce the total cost of the operation,
attaining good mechanical properties for high performance parts. The mechanical properties and the
microstructure features of the considered A 356 alloy and the relative produced parts have been
analysed and studied on samples machined both from the as cast and from the heat treated
compomnents. The obtained results showed the possibility of successfully modifying the T6 heat
treatment cycle with economical benefits, maintaining at the same time comparable high level
properties and performances, together with good dimensional precision.
Determination of Solidification Parameters Used for the Prediction of the Thixoformability of Several Steel Alloys
Authors: Lecomte-Beckers Jacqueline , Rassili Ahmed , Robelet Marc , Poncin Claude , Koeune R.
Published: March 2009

This paper focuses on the liquid fraction curves of several steels and the correlation
between liquid fraction, temperature and heating rate. The work has been performed along two main
axes. First, the solid fraction versus temperature has been obtained experimentally by differential
scanning calorimetry (DSC), limited to low heating rates. Then, a shift of the liquid fraction curves
has been noticed at high industrial heating rates. The quantification of this effect could not be carried
out by DSC and required the elaboration of another experimental device.
Control of Semi-Solid Microstructure of AZ91D Mg Alloys by the Electromagnetic Stirring
Authors: Lim Sung Chul , Lee Heung Bok , Kim Kyung Hoon , Kwon Hyouk Chon
Published: March 2009

Most of the work reported at this conference concerned the semi-solid processing of low
melting point alloys, and in particular light alloys of aluminum and magnesium. Mg alloys are very
attractive as structural materials, because they are the lightest metal among all structural metal
materials and excellent specific strength. The purpose of this paper is to develop a semi-solid
microstructure of Mg alloys using electromagnetic stirring applicable for lighter automobile. The size
of primary solid particle and the degree of sphericity as a function of the variation in cooling rate,
stirring speed, and holding time were observed. By applying electromagnetic stirring, primary solid
particles became finer and rounder relative to as-cast sample. As the input Hz increased from 10Hz to
14Hz, particle size decreased. The size of primary solid particle was found to be decreased with
increasing cooling rate. Also, it decreased with stirring up to 3 minutes but increased above that point.
The degree of sphericity became closer to be 1 with hold time. Semi-solid microstructure of Mg
alloys, one of the low melting point alloys, could be controlled by electromagnetic stirring.
The Use of ADINA Software to Simulate Thixocasting Processes
Authors: Sołek Krzysztof P. , Mitura Zbigniew , Kuziak Roman , Kapranos Plato
Published: March 2009

The main purpose of work was to develop a methodology of physical and numerical
simulation of the thixocasting processes. For the purpose of the studies an experiment was conducted
using a GLEEBLE 3800 simulator. In this work, the GLEEBLE 3800 system was adapted for physical
simulation of the processes of light metal alloy forming in the solid-liquid state. The physical
simulations of thixoforming processes and characterization of thixotropic materials were supported
by computer simulations using ADINA software. The numerical model of thixoforming processes
was developed in order to estimate values of the rheological model parameters.
Design, Construction and Performance of Silicon Nitride Tool Parts in Steel Thixoforming
Authors: Telle Rainer , Muenstermann Simon , Beyer Christophe
Published: March 2009

The design and performance of silicon nitride (Si3N4) dies for the semi-solid processing of steels is
studied by the example of a punch and a lower swage in upset forging. The observed failure mechanisms
and degradation effects are related to short-term effects resulting from mechanical and thermal
loads and long-term effects owing to chemical and tribological attack. Results show that well-defined
process conditions (cycle time, solidification time in the die) and a ceramic-suitable design are a
pre-requisite for reliability and sufficient service life of ceramic dies.
Alumina PVD Tool Coatings for the Use in Semi Solid Metal Forming of Steel
Authors: Bobzin Kirsten , Lugscheider Erich , Maes Michel , Immich Philipp
Published: March 2009

The process of semi solid metal forming with permanent moulds combines the advantages
of the process technologies casting and forging. Semi solid metal forming of steel is a challenge with
respect to very high thermal, mechanical and tribological stresses of tools. Alumina based ceramics
show a very high potential for tool protection. Alumina occurs in different known meta stable phases.
First experiments show that the high temperature γ-phase exhibits high strength and toughness.
Various methods and technologies have examined γ-phase stabilisation by using different thin film
process technologies. By using Physical Vapor Deposition (PVD) it was possible to deposit
γ-Alumina in a temperature range, where hot working steel can be utilized. The properties of the by
pulsed reactive magnetron sputtering deposited films were analyzed by common thin film techniques
revealing hardness, Young´s modulus and coating adhesion. By using the reactive pulsed
PVD-process it was possible to stabilize γ-Al2O3 on steel substrates for semi-solid melt protection.
The γ-Al2O3 coatings showed an extra ordinary stability for thixoforging of X210CrW12 and 100Cr6
in field tests. The durability of the permanent moulds was increased by using PVD thin film coatings
as a tool protection.