bluuebunny/crossref_metadata_2025 huggingface dataset:
MEMS-Compatible Hard Coating Technique of Moveable 3D Silicon Microstructures
Authors: Fekete Z. , Fürjes P. , Kárpáti T. , Gál G.A.B. , Rajta I.
Published: September 2010

Mechanical degradation of mobile silicon components of complex MEMS reduces
device reliability and operation time. Although the considerable wear of the surface micromachined
poly-crystalline elements can be decreased by substitution of crystalline-silicon-based equivalent,
there is still room for further improvement in device durability.
The demonstration device is the recently presented 3D crystalline silicon micro-turbine formed
by the combination of proton beam writing (PBW) and subsequent selective porous silicon (PorSi)
etching. Similarly to the DRIE (deep reactive ion etching) process the novel technique is capable to
provide elements of vertical walls of high aspect ratio.
The 3D silicon components were uniformly covered with LPCVD Si3N4 protective layer. The
Si3N4 coating improves the chemical and mechanical properties; strength, hardness and chemical
resistance. The elaborated processing technology can easily be adapted for deposition of protective
materials of superior properties, e.g. TiN and DLC (diamond like carbon). Present work describes
alternative hard coating technique integrated in the MEMS processing sequence. The feasibility of
the proposed technique is demonstrated by preliminary qualitative wear tests.
Processing of Nano Hydroxyapatite from Eggshell and Seashell
Authors: Gergely Gréta , Wéber Ferenc , Tóth Mihály , Tóth Attila Lajos , Horváth Zsolt E. , Balázsi Csaba
Published: September 2010

Hydroxyapatite (HAp) was successfully produced from recycled eggshell, seashell and phosphoric acid by using two different type of milling method (attrition milling and ball milling). According to the analysis, the attrition milling resulted nanosize HAp even after milling, while the ball milling process provided HAp only after a 400oC, 2 h long heat treatment. The grain size in both cases were approximately preserved during the heat treatment. The effect of temperature on stoichiometry, morphology and crystallinity of HAp powders were investigated. The structures of the HAp were characterized by X-ray diffraction and Scanning Electron Microsopy.
Hetero-Modulus Nanoparticles Reinforced Corundum Matrix CMC with Extreme Wear and Thermal Shock Resistances
Authors: Gömze László A. , Gömze Ludmila N.
Published: September 2010

A novel approach to obtain ceramic matrix composites with extreme high mechanical wear and thermal shock resistance abilities is presented. The developed corundum matrix composites were reinforced with nanoparticles, submicron fibres and whiskers of Si2ON2, SiAlON, AlN and Si3N4. These kinds of materials have several Young’s modulus simultaneously. These new alumina based ceramic matrix composites were obliged to collisions with different metallic bodies having high densities and impact speeds larger than 900 m/s at the moment of the hits. During the experiments in the places of collisions where oxygen was absent new high density „diamond-like” c-Si3N4 cubic crystals have developed with spinel structures, where nitrogen atoms were distributed in the centres of the cubes. These new spinel crystals of c-Si3N4 in the alumina matrix have extreme high dynamic strength, hardness and wear resistance, like diamond. They were fully resistance to oxygen and thermal shock at the tested temperature of 1200 oC.
The Workability of Bulk Nanostructure Material
Authors: Ben Naser Tareg S. , Ree Andras
Published: September 2010

In this work severe plastic deformation (SPD) technique was applied to produce bulk nanostructure material. The ECAP has been used on 6082 type low alloyed aluminium material. Some special compression tests and the forward extrusion technology were used to investigate the further workability of the nanostructured aluminium alloy. This work also includes also the design and manufacture of the forward extrusion die set.
Infiltration Characteristics of Carbon Fiber Reinforced MMCs
Authors: Orbulov Imre Norbert , Németh Árpád
Published: September 2010

Carbon fiber reinforced aluminum matrix composite blocks and a pipe (as semi-product) were produced by pressure infiltration technique. In this paper the authors deal with the production method and investigations of the blocks and the pipe. In our composites AlSi12 eutectic aluminium-silicon alloy was used as matrix material. The reinforcements were ‘A’ and ‘B’ type carbon fibers (‘A’ having lower amorphous carbon content than ‘B’). The volume fraction of the fibers was outstanding – at least 55 vol%. Scanning electron microscopic investigations were done in order to observe the rather rough surface of the carbon fibres. X-ray diffraction and energy dispersive spectrometry was done in order to estimate the quantity of Al4C3 intermetallic phase at the carbon fiber/matrix interface region. The measurements showed that the quantity of Al4C3 strongly depends on the amorphous carbon quantity in carbon fibers. Much more Al4C3 was formed in the case of ‘A’ type reinforcement (less amorphous carbon), than in the case of ‘B’ type reinforcement (more amorphous carbon). The presence of Al4C3 crystals caused large scatter in the mechanical properties, the UTS was decreased, while the compressive strength was increased. Fracture surfaces were investigated: the composite showed rigid fracture.
Alloying and Amorphization by Surface Mechanical Treatment
Authors: Revesz Adam , Takacs Laszlo
Published: September 2010

Metallic plates were coated mechanically with powders by surface treatment in a SPEX 8000 Mixer Mill. Al disks were coated by harder Ni particles, while a Zr-Ti powder blend was deposited onto Cu targets. The microstructure and morphology of the coatings were investigated by scanning electron microscopy and X-ray diffraction. Mechanical properties were studied by dynamic hardness tests.
Investigation of the Weldability of the Self-Reinforced Polypropylene Composites
Authors: Kiss Zoltán , Kmetty Ákos , Bárány Tamás
Published: September 2010

In the present work the weldability of self-reinforced composite was investigated. As reinforcement a fabric, woven from highly stretched split PP yarns, whereas as matrix materials of two kinds of random polypropylene copolymer (with ethylene) were used. The composite sheets were produced by film-stacking method and compression molded with different thickness (1 mm,
2 mm) with different contents at different processing temperatures keeping the holding time and pressure constant. The SRPPC sheets were welded by ultrasonic welding machine with different welding parameters. The welds were qualified by mechanical and microscopic tests. The results showed that the thermoplastic reinforcement has not got melted; therefore the reinforcement was kept the strength-increasing effect.
Production of Polymer Nanofibers Containing Hydroxyapatite by Electrospinning
Authors: Tóth Mihály , Gergely Gréta , Lukács István Endre , Wéber Ferenc , Tóth Attila Lajos , Illés Levente , Balázsi Csaba
Published: September 2010

Hydroxyapatite (HAP) is the main inorganic component of mammal bone and teeth. It is one of the few bioactive materials, which helps cell growing. The objective of this study was to fabricate hydroxyapatite-biopolimer nanofiber mats. To achieve this goal, two different suspensions were used. Approximately 1 μm diameter size fibers with large HAP agglomerates were fabricated using acetone and acetic acid. Fibers with a larger diameter size and homogenous distributed HAP particles were produced applying acetone and isopropanol. During the experiment the effect of the processing parameters: applied voltage, diameter of needle, the distance of the needle tip and the collector, flow rate was analyzed.
Investigation of the Influence of Surface Strengthening Technology on the Material of Railway Car Wheel Axles
Authors: Berecz Tibor , Balogh Levente
Published: September 2010

Surface rolling is a cold-working technology for hardening the surface of components made from steel or ductile cast iron. This process is able to increase the hardness of surfaces and to improve fatigue properties, so it is usually used on axles (shafts) of railway car wheels. In this paper the influence of surface strengthening technology on the microstructure of the material of railway car wheel axles is studied by micro hardness tests, optical microscopy, scanning electron microscopy (SEM) and X-ray line profile analysis.
Stent Retention Measurement
Authors: Bognár Eszter , Balázs Tibor , Ring György , Szabó Barnabás , Nagy Péter
Published: September 2010

This article introduces two original measurement methods (i.e. adhesive layer and pulloff
edge) for the determination of the stent retention force, together with the results from these
measurements. The measurement with the adhesive layer models and quantifies the stentobstruction
occurring in the constrictions; meanwhile the pull-off edge method is based on
modelling and quantifying the collisions and constrictions in the main catheter. For the evaluation
of the measurements our research introduced the specific ‘stent pull-off’ force, which shows the
force required for the ‘pull-off’ of the stent from the balloon, which is referred to as the stent unit
length. This is the maximum force value shown on the retention diagram (insert diagram reference
here). It is ascertainable, that the presence of the polyurethane coating and the increase of the
pulling-speed are increasing the ‘stent pull-off’ force. During the test interval of the pull-off speed,
the ‘stent pull-off’ force for the Chronoflex®-coated stents increased from 0.45 N/mm to
0.76 N/mm.
Measuring of Equibiaxial Tension of Rubber-Like Materials by Optical Method
Authors: Bojtos Attila , Huba Antal , Zentner Lena , Risto Uwe
Published: September 2010

For the simulations of elastic constructions actuated by inner pressure we need for the
definition of the material model parameters, the data originating from the biaxial test. The paper
reviews the biaxial material testing methods, especially the bubble inflation methods. It contains a
short summary of the stress analysis of the rotation ellipsoid shells in association with the bubble
inflation. The paper shows a developed equibiaxial inflating test using optical measurement method.
Two different methods using image processing are showed. The test result of an examined silicone
rubber (MED-4930) is presented with it’s material parameters.
Study of Aluminium-Titanate Based Ceramics in Fe2O3-Al2O3-TiO2 System
Authors: Korim Támas
Published: September 2010

Solid solutions formed within the Al2O3-TiO2-Fe2O3 (Fe2xAl2(1-x)TiO5) system upon heat treatment were investigated by adjusting the substituting Fe3+ content in the range of x=0.0 to 1.0.
X-ray diffraction phase analyses and lattice parameter determinations confirmed that substitution of Fe3+ ions within the aluminium titanate lattice was complete.
For this complete solid solution, however, the trends observed for changes in d-spacing values indicated that there were certain discrete compositions to identify with Fe3+ substitution. Within these, Fe0.4Al1.6TiO5 and Fe1.6Al0.4TiO5 crystalline phases were investigated in detail and their
X-ray diffraction cards were constructed.
Self-healing effect occurring in repeated heating-cooling cycles in Fe3+ doped AT ceramics were proved; it was demonstrated that Fe3+ doped AT ceramics do not decompose even if exposed to repeated thermal shock.
Mechanical Testing of Si3N4/SiC/Graphite Ceramic Composites
Authors: Koncsik Zsuzsanna , Berkes Maros Maria , Kuzsella László
Published: September 2010

Pin-on-disc tribological tests were performed on Si3N4/SiC/graphite ceramic composites
with 5N applied load, at room temperature in dry conditions. Tests were completed with
microhardness tests (F=10N), indentation fracture toughness tests (F=100N), furthermore
morphological analyses of the wear tracks by SEM. Based on SEM pictures of the wear traces the
main damage mechanism could be identified as an abrasive wear.
The purpose of the paper is to model the abrasive wear of the given composites. For this reason
lateral crack chipping model suggested by Evans and Marshall for Si3N4 ceramics was used for the
assessment of the worn volume of the abrasive wear process. The model has been applied with the
aim of validating it
Laser Treatment of Cast Iron Engine Cylinder Bore with Nanosecond Laser Pulses
Authors: Májlinger Kornél , Szabó Péter János
Published: September 2010

The environmental and polluting materials emission standards in Europe are going to be always stricter, so in order to keep up with them, one of the largest European automotive manufacturer performs a laser treatment on the cylinder bores of their internal combustion engines. Due to the laser treatment, the near surface area of the cylinder bore becomes harder and more wear resistant, furthermore, due to the inhomogenity of the pearlitic matrix and graphite lamellae, oil reserving holes are formed.
In our present work we investigated the laser treated layer of cast iron cylinder bores with lamellar graphite. Samples prepared with two different lasertypes and different energies were investigated on behalf of metallographic and functional aspects.
Measuring the Heparin Binding Capability of Polyurethane-Coated Stainless Steel Stents with a Label-Free Biosensor
Authors: Puskás Zsolt , Toldy Árpád I. , Ginsztler János
Published: September 2010

In the development of modern drug eluting implants it is crucial to be able to measure the long term desorption processes which determine the drug elusion. In this article we set up a simple model for these measurements, which consists of stainless steel stent-model samples with polyurethane coatings incubated in heparin, and a label-free OWLS (Optical Waveguide Lightmode Spectroscopy) biosensor to measure the elusion of heparin from these samples. We found that porous coatings bind heparin better than smooth coatings, and that the PUR materials tested by us all have different binding properties. We also constructed a dual-flow set-up for the instrument, which enabled us to do real-time elusion measurements instead of sample injection, which would make the monitoring of desorption processes much clearer, although this measurement method is yet to be fully developed.
Trackability and Flexibility of Coronary Stents
Authors: Szabadíts Péter , Dobránszky János
Published: September 2010

Coronary stents are the most important materials in our days cardiology. Flexibility and trackability are two basic features of stents. In this paper seven different balloon-expandable coronary stent systems were investigated mechanically in order to compare their suitability. The coronary stent systems were assessed by measurements of stent flexibility as well as by comparison of forces during simulated stenting in a self-investigated coronary vessel model. The stents were cut by laser from a single tube of 316L stainless steel or L-605 (CoCr) cobalt chronium alloy. The one- and four point bending tests were carried out to evaluate stent flexibility E∙I (Nmm2), under displacement control in crimped and expanded configurations. The flexibility of stents would rather dependent on the design than raw material. In generally the more flexible stent needs lower tracking force during the implantation. The L-605 row material stents need lower track force to pass through in the vessel model as the 316L row materials stents. In the curve of the vessel model the sort and long stents passed through in different ways. The long stents nestled to the vessel wall at the outer arc and bent, while the short stents did not bend in the curve, only the delivery systems bent.
Compositional and Stress-Sensitive Factors during the Thermopower Characterization of Single Phase Crystalline and Glassy Alloys
Authors: Szabó A. , Weltsch Zoltán , Lovas Antal
Published: September 2010

For the study of stress state in engineering alloys, the thermopower (S) measurement could be acceptable method after a suitable calibration (fitting the S value to the change of well known other physical parameters like the magnetic coercive force, hardness or strength increase during various thermomechanical treatments). For this purpose a simple equipment is constructed and built by which the S shift can be measured versus the increasing mechanical tensile load. The first results will be published in this paper, obtained on various metallic glass ribbons.
The Transformation of Added Vegetal Waste Materials during Clay Brick Firing
Authors: Kristály Ferenc , Gömze László A. , Papp István
Published: September 2010

Vegetal materials are generated in high amounts and are applied as additives in clay bricks since ancient times. They have a certain heat contribution to the firing process. As revealed by X-ray Powder Diffraction, main component of vegetal waste materials is cellulose. Thermal and Evolved Gas Analysis revealed the combustion process in its details. Mixtures of clay and vegetal additives prepare for test bodies were analyzed by Thermal Analysis. The thermal effects were quantified by Differential Thermal Analysis and correlated with Thermogravimetry and Derivative Thermogravimetry.
Study of Non-Monotonity of Forming Processes Using Finite Element Analysis
Authors: Bobor Kristóf , Krallics György
Published: September 2010

The method of severe plastic deformation is often used to produce bulk ultra-fine grained materials. Numerous methods exist, which are able to produce ultra fine grained materials. Investigated the mechanical schema of these procedures, we searched for such attributes, which characterize the mentioned techniques. By our previous researches can be established, that for these techniques shear deformation as well as the so-called non-monotonic deformation are characteristic. In this paper a degree of non-monotonity is presented, which is an appropriate measure to characterize the forming processes. Besides this the combined Euler – Lagrange method is showed, which is appropriate to obtain a continuous velocity field from finite element analysis. Eventually the mechanical analysis of the extrusion, conventional and asymmetric rolling is showed with respect to the non-monotonity.
Parameter Identification Methods for Generalized Maxwell Models: Engineering Approach for Small-Strain Viscoelasticity
Authors: Bódai Gábor , Goda Tibor
Published: September 2010

The present paper surveys briefly the parameter identification methods widely used in
case of generalized Maxwell-model. Beside those basing on dynamical-mechanical thermal analysis
(DMTA) and stress relaxation measurement authors have presented a technique using simple tensile
tests. The latter can be effectively used by combining it with the genetic algorithm of Matlab for
parameter identification in a limited frequency/time domain. The proposed method can be
generalized easily for example for shear and compression tests too. After comparing it with other
existing methods author make a proposal for the strain rate of the uniaxial tensile test.
Simulation of Phase Transformations Driven by Short Range Diffusion by Cellular Automaton
Authors: Gyöngyösi Szilvia , Tóth Anita , Barkóczy Péter
Published: September 2010

The same property of the phase transformations driven by short range diffusion (recrystallization, allotropic transformation, grain coarsening) is that the movements of the grain or the phase boundaries take place by atomic jumps through the boundaries. The probability (frequency) of these jumps depends on only on the energy state of the closenear neighborhood of the atoms. In the operation of cellular automata Consequently, only the closenear neighborhood of the cells is taken into account in the operation of the cellular automaton. This similarity makes applicable the cellular automaton applicable to simulate the aforementioned phase transformation processes. A condition (rule) of the movement of grain and phase boundaries is introduced, which makes it possible to simulate all the all mentioned phase transformation by the same automatona.
Calculation of the Immiscibility Gap by ESTPHAD Method
Authors: Mende Tamás , Roósz András
Published: September 2010

By using the thermodynamic equations, the ESTPHAD (Estimation of Phase Diagrams) method developed by us has been made suitable for calculating the immiscibility gap of monotectic systems. 2 special parameters were introduced in the basic equation of ESTPHAD which ensure the description of the characteristics of monotectic curve on the basis of the boundary conditions created by us. By means of the monotectic ESTPHAD equation, the equations of separation temperatures of monotectic parts in the Zn-Bi and Al-Bi systems were calculated (with an accuracy of +/- 10K) on the basis of the reference data.
Mathematical Modeling on Welding Phenomena
Authors: Palotás Béla
Published: September 2010

The development of computer technology has been followed by welding as well, in the last 15 years. It is true for software development and it is true for hardware application. The paper gives a summary of computer technology application and mathematical modeling in welding, with a demonstration of software development and modeling activities carried out in Hungary. After some statistical data about software application in welding, this paper demonstrates the differences between handling databases, calculation software and elements of Artificial Intelligence. Some of the most important results of software development carried out at the Budapest University of Technology and Economics (BUTE) are also introduced in this paper.
Mathematical modeling is a very important part of information technology development in the case of welding as well.
Classification of Fullerene Isomers Using Local Topological Descriptors
Authors: Réti Tamás , László István , Bitay Enikő , Došlić Tomislav
Published: September 2010

. A method for the structural classification of fullerenes via graph invariants is presented. These graph invariants (called edge-parameters) represent the 9 different types of bonds existing in fullerenes between two neighbouring carbon atoms and they are also applicable to classify the fullerene isomers into equivalence classes. Discriminating performance of edge-parameters has been tested on the sets of C40 and C66 fullerene isomers. It is shown that the stability of C40 and C66 isomers can be efficiently predicted using a novel topological descriptor (Ω) defined as a function of four appropriately selected edge parameters.
Shape Features of 2D Figures
Authors: Szakál Zoltán , Zsoldos Ibolya
Published: September 2010

The symmetry-diagram was originally defined for symmetry recognition. As a consequence it has been proven that the symmetry-diagram shows the unique shape property of the two-dimensional (2D) figures. The symmetry-diagram is different in the case of 2D figures having a different shape. It is very sensitive to the smallest change in the shape. The only exception for its applicability is the 2D figure having two or more concentric boundary loops.
3D Milling by Micro Electrical Discharge Machining
Authors: Farkas Balázs Zsolt , Takács Márton
Published: September 2010

One of the most important tasks of the manufacturing engineering of our accelerated world is giving suitable answer to the ever growing demand on miniaturization arising on every field of the industry. Our institute has been carried out theoretical and experimental research work on micro machining since 10 years. Micro machining can be defined as formation of structures smaller than 1 mm. Our previous research activity focused primarily on micro milling process carried out by carbide end mill. Milling offers the most various machining method among the chip removal processes. Investigation of formation of micro structures by electrical discharge machining (EDM) is a perfect continuance of the research work. A process similar to micro milling can be realized by the lateral moving of the miniature cylindrical electrode of an EDM machine, just the physical principle of material removing is different. This paper introduces the latest results of our research work, including
Characterization of Mineral Materials as Asphalt Fillers
Authors: Geber Robert , Gömze László A.
Published: September 2010

In this work the Authors are dealing with the utilization of mineral fillers used in the Hungarian road construction. Six different types of mineral fillers – andesites, basalt, dolomite and limestone – were tested. In the purpose of the applicability of mineral aggregates in road construction XRD, BET specific surface test, as well as SEM tests were made and hydrophilic coefficient of fillers were also determined.
The results of the XRD, BET specific surface test, SEM and hydrophilic coefficient tests show that all of the examined fillers are suitable for asphalt-technological applications, particularly limestone filler (Alsózsolca) and dolomite filler (Pilisvörösvár).
Optimization of the Mixing Ratio of Two Different Clays Used for Ceramic Roof Tiles
Authors: Geber Robert , Kocserha István , Orosz Viktor , Simon Andrea , Paróczai Csilla
Published: September 2010

Brick- and tile manufacturing is one of the most rapidly developing industries. Professionals are constantly seeking modern technological solutions with which much better and longer lifetime of ceramic roof tiles can be reached.
The aim of this R&D work was to optimize the mixing ratio of two different clay minerals of the industrial partner. The Authors have tried to develop a mixture by increasing the mixing ratio of the clay „Jamina”, which reaches or exceeds the mechanical strength and frost-resistance of the ceramic roof tiles which were made according to the present recipe used by the industrial partner.
After XRD tests in virtue of preliminary mixture design, the Authors have made clay mineral mixtures that were milled and homogenized in an edge mill for an appropriate grain size. After mixing and homogenizing, samples with different length were made for further investigations with the use of a laboratory vacuum extrusion system. Shrinkage after drying and firing, apparent porosity and water absorption were measured on these samples. Mechanical test were also executed, as well as bending strength tests and compressive strength tests.
On the basis of the results of the executed tests, it can be seen that the Authors were successfully developed clay mixtures, with which ceramic roof tiles can be produced with properties that are more favourable than the present mixture used by the industrial partner. The increase of the ratio of ‘Csaba I.’ clay increases the bending and compressive strength of the fired ceramic roof tiles. So the reduction of the amount of clay „Jamina” affects the mechanical properties of the ceramic roof tiles favourably.
Fatigue Crack Growth Examinations on Austenitic Stainless Steel in Corrosive Environment and at Elevated Temperature
Authors: Lukács János
Published: September 2010

There are different documents and standards containing fatigue crack propagation limit or design curves and rules for the prediction of crack growth. The background of the curves and the calculations consist of two basic parts: statistical analysis of numerous experiments and a fatigue crack propagation law. The research work aimed to measure basic data for limit curves on austenitic stainless steel, in corrosive environment and at elevated temperatures, and to determine the design curves based on statistical analysis of measured data and a fatigue crack propagation law. Experiments were performed on modified CT specimens, in water solution and at two different temperatures. The fatigue crack growth tests were executed by constant load amplitude method. In order to study the hold time effect, fatigue crack growth tests were terminated and hold time period was applied. It can be concluded that the modified CT specimens are suitable for fatigue crack growth tests in corrosive environment; the fatigue crack propagation characteristics are different at different testing temperatures; and stable crack propagation and/or crack tip blunting can be detected during the hold time period at the used higher testing temperature.
Effects of Extruder Head’s Geometry on the Properties of Extruded Ceramic Products
Authors: Kocserha István , Kristály Ferenc
Published: September 2010

A plastic brick clay with high clay mineral content was selected and the effects of different extruder heads on the main physical properties of the extruded products were investigated. The raw material was processed by a laboratory extruder after homogenization and wetting. Extruder heads with conical and special (spherical and torus) inner shape were applied to form and produce the green products which were examined after drying and firing. The rotation of the extruder screw was also varied between 15-55 1/min. Applying optical microscopy and SEM, the structure of the green products was analyzed. In addition to the physical properties of the products, the pressure caused by the extruder heads was determined by theoretical calculation and measurement. The results revealed that the physical properties of the products could be changed only by changing the shaping die geometry when the product size and production method remained unchanged. Maximal compressive strength of fired brick products (35.45 MPa) was obtained in case of the spherical head while the use of torus head caused some 5% decrease in the power consumption of the extruder. The density of fired products decreased and water adsorption increased when the rotation speed of the extruder screw was increased. The measurements confirmed the theoretical order of the applied extruder heads in terms of capability of pressure generation.
Investigation of Laser Brazing of Aluminium
Authors: Markovits Tamás
Published: September 2010

Use of aluminium materials has increased in the vehicle industry in the last years due to their low weight. Machining of aluminium by industrial lasers is a more complex task than that of steel because of the lower absorption, higher heat conduction, higher heat capacity and oxide layer on the surface.
The low absorption ability of the Al surface can be significantly improved by using appropriate brazing flux suspension on the wavelength of CO2 lasers.
In this paper the role of brazing flux components and their influence are investigated in the heating efficiency in case of Nd:YAG lasers, which are widely used in the laser joining technology. This research work presents the differences between the effects of the brazing flux in case of CO2 and Nd:YAG lasers.
The Role of the External and Internal Reinforcing on the Structural Integrity of Industrial and Transporting Steel Pipelines
Authors: Lukács János , Nagy Gyula , Török Imre
Published: September 2010

The lifetime management of different engineering structures and structural elements is one of the important technical-economic problems nowadays. On the one hand, the aim of our research work is to develop an integrity management plan for pipelines and pipeline systems, and afterwards a Pipeline Integrity Management System. Material databases play important role both on the integrity management and on the engineering critical assessment of the pipeline systems. On the other hand, the aim of our research work is to establish the Pipeline Integrity Management System with different data, frequently with experimental data. The direct purpose of the paper is to present the role of the external and internal reinforcing on the structural integrity of industrial and transporting steel pipelines, based on own examinations. External and internal reinforcement was developed using carbon fibre and glass fibre polymer matrix composites, respectively. Fatigue and burst tests were performed on pipeline sections containing natural and artificial metal loss defects, and girth welds including weld defects. Both unreinforced and reinforced pipeline sections were examined. The burst pressures belonging to the unreinforced and the reinforced pipelines, and belonging to the passed and not passed girth welds were compared.
Fatigue of Laserbeam Welded Joints of High-Carbon Steel Strips
Authors: Magasdi Attila , Ginsztler János , Dobránszky János
Published: September 2010

The high-carbon steel strips are one of the most widely used base materials of bandsaw blade manufacturing. These materials have sufficient strength and ductility to cope with the high fatigue load of the bandsaw blades. These endless strips are produced by welding, and therefore the weld and the heat affected zone have different mechanical properties, like tensile strength and fatigue resistance, than the base material. These properties of the weld can be influenced by preheat and post weld heat treatment. Regarding to the latest industrial requirements, the application of laserbeam welding was examined to produce higher standard bandsaw blade. The laserbeam welded joints has lower heat input and narrower heat affected zone compared to metal inert gas (MIG) welding, which is currently used in bandsaw blade manufacturing. To assure the proper mechanical properties and sufficient resistance to fatigue, an examination was carried out to determine the effect of preheat temperature and post weld heat treatment time on the mechanical properties and fatigue behaviour of the laserbeam welded joint.
Examination of Tile Industrial Usability of High-Quartz Content Clay
Authors: Orosz Viktor , Kocserha István , Geber Robert , Paróczai Csilla
Published: September 2010

The Hungarian roof tile plants settle near a discovered clay mine in every case thus they work with different content clays. Examining characteristics of certain clay layers is needed to ensure stable product quality. Some clay layers with significantly different content occur among the presently used ones, which need an extensive examination for the production of good quality items. Results of high quartz content clay usability examinations are shown in this paper. The aim of examinations is to determine the usability of frequently occurring high quartz content clays. In the course of tests high quartz content clay mineral was mixed in increased amounts to clay mineral for roof-tile production provided by the industrial partner. Shrinkage, porosity and mechanical properties were examined as a function of mixing ratio.
Cold Deformation Effect on Microstructure and on the Hydrogen Permeability of Low Carbon Al-Killed Steels
Authors: Enikő-Réka Fábián
Published: September 2010

The cold rolling effect on the hydrogen permeability (TH value) and on the microstructure have been studied on samples prepared from Al-killed low carbon steel sheets after several cold rolling levels. The TH values of the hot rolled strips were very short, but due to the cold rolling increase exponentially. The fragmentation of large cementite phase has a significant influence on the evolution of texture during the cold rolling process. The cold deformation effects on the TH value were studied on four annealed enamelling grade steel sheets also. Depending on the carbides sizes and carbides position in ferrite grains after annealing the TH values increase or decrease after low deformation degrees, due to the steel texture modification and dislocation character. Dislocations act as major tripping site for hydrogen, if deformation degree is higher than 30%.
A Method for the Approximate Determination of the Specific Material Properties of Metals under the Extreme Conditions of Fast Deformation
Authors: Pálmai Zoltán
Published: September 2010

The common feature of the different forming technologies is that the deformation is concentrated into a relatively narrow shear zone. The behaviour of the material can be defined only by specific material properties, the definition of which is difficult and costly. We have developed a new method for the comparatively simple and cheap definition of these specific material properties based on the well known theory and the sophisticated measuring technology of cutting. To achieve this we have developed our previous dynamic technological model, which is described by evolution and delay differential equations. As an example, in the case of a steel with 13% Cr content T, C555520−≈8.26.2−≈=φεγ, the thermal softening 4410−−≈=sφεγ&&≈κ0.98±0.016 MPa/K, the strain rate sensitivity constant k≈0.034±0.009 and the strain hardening exponent n0.170.005.
The Effect of Pre-Electron Beam Irradiation of HDPE on the Thermal and Mechanical Properties of HDPE/PET Blends
Authors: Ronkay Ferenc , Mészáros László , Jánoki Gábor , Czvikovszky Tibor
Published: September 2010

The effect of electron beam (EB) irradiation of high density polyethylene (HDPE) on polyethylene-terephthalate (PET)/HDPE blends has been investigated. The HDPE component was radiation treated before the blend was melt mixed. Although the radiation treatment of HDPE component with 50-200 kGy caused some decrease in the tensile strength and elasticity modulus, the maximum tensile elongation of the blend showed a significant increase (+40%) at optimum dose (100 kGy). The DSC results and the scanning electron microscope images of the fracture surfaces also showed the benefit of a 100 kGy EB-dose in the connection the otherwise thermodynamically incompatible part of the blend.
The Effect of Electron Irradiation on the Mechanical Properties of MWCNT/Carbon Fiber Reinforced Hybrid Nanocomposites
Authors: Szebényi Gábor , Romhány Gábor
Published: September 2010

In our work carbon fiber/epoxy composite and multiwalled carbon nanotube/carbon fiber/epoxy hybrid nanocomposite laminates have been prepared by resin transfer moulding (RTM) technology. The specimens have been irradiated using a high energy electron gun with multiple doses. The effect of the electron irradiation has been characterized using three point bending, interlaminar shear and instrumented falling weight impact tests.
Rapid Tooling Technologies in the Processing of Thermoplastic Polymers
Authors: Szenti Alexandra , Tuba Ferenc , Kovács Norbert Krisztián
Published: September 2010

Thousands of people are affected by the newest achievements of material science and manufacturing technologies each year in the form of biomedical implants. In this field, the aim of developement is to create individual implants to satisfy the geometrical and adapting requirements of the patient. This manufacturing process has been recently improved by shortening the cycle time and using cost effective methods. Biocompatible thermoplastic polymers can be shaped with hot pressing technique. Rapid Tooling was used to create a forming tool for manufacturing process. 3D Printing was used to fabricate the computer generated forming tool. This tool was reinforced by infiltrating it with an epoxy resin. Different epoxy resins were examined to secure the best mechanical properties of this tool. Then the reinforced tool was used for hot pressing of the biocompatible thermoplastic polymer, poly(ε-caprolactone).
Actuation Strategy for a New Driving Simulator Setup
Authors: Capustiac Alina , Unterreiner Michael , Schramm Dieter
Published: September 2010

This paper focuses on the actuation strategy of an active driving simulator and its validation using experimental driving data. The simulator combines the simulation of both the road characteristics and the vehicle dynamics into a single architecture. The goal is to combine actual road excitation signals with imposed vehicle movements to create a realistic driving experience.
Wearable Exerciser
Authors: Chetran Beniamin , Lungu Ion , Aluţei Alexandra Maria , Mândru Dan
Published: September 2010

In this paper we present a new compact and portable rehabilitation system. It's role is to provide therapeutic passive motions of the hand. The anatomical characteristics and the biomechanics of the wrist are emphasized. The target anatomical movements of the hand are flexion-extension and abduction-adduction. A comparative study of similar devices is presented. The principle of operation of chosen variant is given. Its design methodology is detailed. A functional prototype was developed and its functional parameters are presented.
Video Camera Measuring Application Using Matlab
Authors: Coman Mircea , Radu Balan
Published: September 2010

This paper presents the implementation in the Matlab/Simulink environment of an application for measuring distances using a video camera. Some of the advantages of using image processing as a method of measurement and of the Matlab for designing de application. The principles that where use to obtain de distance calculated where presented. Also the steps of the application implementation in Simulink where described.
Intelligent Robot with Microcontroller for Obstacles Avoiding
Authors: Dragomir Florin , Patic Paul Ciprian , Dragomir Otilia Elena
Published: September 2010

The paper describes a intelligent robot with two stepper motor and microcontroller PIC16F84A for obstacles avoiding (IRSMP). An experimental prototype, based on a stepper motor, microcontroller PIC16F84A and infrared sensors, has been realized using conventional digital circuits. The proposed control scheme can be usefully applied to any intelligent robot. The infrared sensors has using for obstacles avoiding. The program for microcontroller is making in assembler language.
The Analysis of the Weaving Wire’ Mechanism Using CosmosMotion under SolidWorks
Authors: Filip Viviana , Negrea Alexis , Dobra Gabi
Published: September 2010

In the first part of this paper, there are presented the computing relations for kinematic (getting the velocity and the accelerations) and kinetostatic (getting the reactions – force and moment from the links) of a plan mechanism which has five elements. In the second part of the paper, there is a three-dimensional model of the mechanism created of SolidWorks and the analysis of this mechanism motion using COSMOSMotion under SolidWorks, the goal is a comparison between the results that we obtained on analytical way and the ones from this program.
A Fuzzy Model for Establishing Two Main Parameters of GTAW Process
Authors: Gorghiu Gabriel , Patic Paul Ciprian , Cârstoiu Dorin
Published: September 2010

In the last period, the quality and productivity of arc welding operations increased more than ever, especially in the areas that require high technology, represented mainly by the aerospace and nuclear industry, which led naturally to automation and robotics welding operations.
The paper proposes a fuzzy system for the establishing of the main control parameters (welding current and welding speed) function of two important input parameters (plate thickness and diameter of the non consumable tungsten electrode). In this way, one of the actual modeling techniques (fuzzy logic) can be extended in welding technologies as an alternative tool, being particularly attractive for automated and robotized welding processes.
Automation of Logistics Processes by Using a Universal Control
Authors: Kirchheim Alice , Echelmeyer Wolfgang
Published: September 2010

Due to the globalization companies are forced to implement efficient processes. Automation is a chance to reduce costs especially for repeative tasks. But by now it causes high costs for companies to integrate robots especially in case of individual systems for specific tasks. Due to the changing goods and working spaces within logistic processes automated systems have to be developed with respect to the task. The universal control computes an inverse kinematic based on application based data, executes an efficient path-planning and collision detection. This approach results in decreased develop costs for system-integrators, decreased costs for service and maintenance as less expert know-how is necessary and it results in shorter integration time, less system-failure due to the usage of standard components.
Dynamics of Hybrid Robot Structures Using Variational Principles
Authors: Negrean Iuliu , Vuscan Ioan , Schonstein Claudiu , Kacso Kalman , Duca Adina , Negrean Calin
Published: September 2010

The purpose of this paper is to determine the dynamic equations for a hybrid robot structure which consists of a mobile robot named PatrolBot and a 2TR robot serial structure. The motion equations will be determined on the basis of the new concepts in advanced mechanics, such as Matrix Exponentials Algorithm and Variation Principles in Analytical Mechanics, concerning the kinetic and acceleration energy part of important scientific researches deployed by the main author.
Socially Assistive Robots and Autism
Authors: Nikolopoulos Chris , Kuester Deitra , Sheehan Mark , Dhanya Sneha , Herring William , Becker Andrew , Bogart Lauralyn
Published: September 2010

Socially Assistive Robotics is a newly emerging area of robotics where robots are used to help a human through social interaction. This paper describes an ongoing project on the use of robotics as therapeutically or educationally useful tools for treating individuals with Autism Spectrum Disorders (ASD). The robotic Lego NXT platform was used to develop an economical, practical and efficient means of helping teach social behavior to individuals with ASD in school/home environments. In addition, our approach to treatment is described as an educational intervention which is a combination of Socially Assistive Robotics, the DIR/Floortime intervention model and social script/stories.
Research Concerning the Ramp and Sinusoidal Command Signals of the Piezoelectric Miniactuators
Authors: Noveanu Simona , Mândru Dan , Ivan Alexandru , Csibi Vencel Iosif
Published: September 2010

In this paper is presented a mini-system with compliant minigripper and piezoelectric actuation. The piezoelectric actuator is controlled with ramp and sinus signals. The response of the mini-system is predicted by the finite elements method. The displacement of the compliant mini-gripper and piezoactuator are analyzed. In the end is presented a comparison of the experimental results for same actuator but for two different types of the signals with theoretical results.
Kinematics Investigation, Workspace Analysis and Actuators Design for a 2-DOF Redundant Parallel Robot
Authors: Rad Ciprian , Rusu Calin , Balan Radu
Published: September 2010

This paper discusses the inverse and forward kinematics problem for a 2-dof parallel robot with actuator redundancy. The reachable workspace of the robot is generated for a set of parameters and a solution for the actuators is proposed in the final.
A Novel Method for Rural Road Construction Planning Using Quad-Tree Decomposition on the Satellite Image
Authors: Shojaeipour Shahed , Nejad Abbas Tahmasebi , Masoomi Mohammad Saeed , Mokhtarian Hamid Reza , Jahanshahi Ali
Published: September 2010

Rural roads construction projects are expensive, this has led to difficulties in developing accurate construction plans and modeling the construction operation using a novel simulation system. In this field, the aim of this research is to create a knowledge driven rural road construction simulation system to assist satellite image in generating s and reliable road construction plans.
Road construction operations of the resources have been identified, developed, classified and modeled through a comprehensive analysis of a Simulink road construction projects. For every road construction operation a GIS-based template for little models was defined and developed. The models abridge distance of the path on the roads construction between villages and automating the optimizing of works. Also, the models provide a roadmap for evaluating several shortest paths on road construction via Quad-tree decomposition of the satellite image.
A simulation case study was modeled to identify applicability, usefulness and accuracy of the developed simulation system and results are presented in this paper. The study fulfilled that the system generated for fast marching.