bluuebunny/crossref_metadata_2025 huggingface dataset:
Window Structures in Building with Historical Building Preservation
Authors: Vavrovič Boris , Puškár Anton
Published: January 2016

The building of Faculty of Architecture SUT in Bratislava can be considered by its character and complex design as one of mature works of architect prof. Emil Belluš, DrSc. It is proofed not only by architectonic and spatial concept, but also overall technical facilities, details design and used material scale and their technical and handcrafted quality. The building was constructed in years 1950–1952. The window structures of building are not only the distinguished structural elements but also they are phraseology of the architectural work. They belong to relevant façade structural elements while, at the same time, they determine format, aesthetic impression and façade value. Due to extensive window defects which, in many cases, caused as much as a function loss, it was necessary to change them. The requirements of specialists for listed buildings comprised the preservation of material, facial, colour and function design with the aim of energy saving.
The Algorithm of the Double-Skin Façade without the Effects of Wind
Authors: Palko Milan , Palková Adela
Published: January 2016

The article is focused on the theoretical calculation of double-skin façade without effect of wind. Each algorithm needs entry figures for initiation, so that the computing could be started. Incoming data entry of this computing program consists of two parts - geometric and physical parameters of double-skin façade. Calculation of the mass flow in inter-space is a highly complex matter. Particular unknown quantities in heat computing and air mass flow are unknown and interdependent to each other. Algorithms of their specification by iteration method are processed for designation of these values.
Condensation on the Exterior Surface of Glass System
Authors: Palková Adela , Palko Milan
Published: January 2016

The problem of outer condensation occurs considerably towards the end of summer and early autumn. Surface condensation on the outside of the glazing is rare in the corners, given the fact that the outer edges of the glazing are heated due to a thermal bridge. The coldest point on the outside of the glazing is generally in the middle with the lowest level of heat losses. Surface condensation of water vapour appears on the external surface of an insulating glazing, if the temperature at the surface of the glazing is substantially lower than the air temperature and if it drops below the dew point.
Impact Wind Turbines Implementation in Municipalities in the Context of Sustainable Urbanism with Focus on Dynamic Pedestrian Comfort
Authors: Hépal Martin , Puškár Anton
Published: January 2016

The article, in the context of sustainable urbanism, reflects current tendencies of small urban wind power plants implementation into municipalities. There is an emphasis on wind as one of the aspects of architectural design and urbanism. Due to extensional interdisciplinarity of the examined phenomenon, the article captures a wider framework of the issue. The sustainability objectives in the creation of settlements - housing environment are emphasized. By the overview of wind turbines and selected research papers article demonstrates the current state of the subject. Yet the research points out that dynamic pedestrian comfort is not being taken into account and chosen geometries are not suitable. The article outlines visions and possibilities of implementation of small urban wind power plants while correctly using tools, techniques and qualitative and quantitative parameters.
Atmospheric Boundary Layer Modelling
Authors: Vranková Andrea , Palko Milan
Published: January 2016

The aim of the paper was to define the input options over the boundary layer, as the entrance boundary conditions for simulation in ANSYS. The boundary layer is designed for use in external aerodynamics of buildings (part of the urban structure) for selected sites occurring in the territory of the Slovak Republic.
Fire Safety of Buildings in the Protection Zone of the Electric Power Transmission System of the Czech Republic
Authors: Trčka Martin , Ondruch Jan , Thomitzek Adam , Kavan Štěpán
Published: January 2016

The article presents possible procedure for determining parameters of a building representing a finite group of buildings of the same properties characterized in particular by their size and amount of combustible material (family house furnishings, manufacturing facilities, etc.) that are potentially threatened by overhead electric power transmission lines. Detailed statistical processing was used to find dimensions of these buildings such as length, width, and height and their distance from transmission line conductors, which the first step is preceding subsequent mathematical modeling of a representative building and simulation of a fire in it.
Load Bearing Structures of Glass Single-Storey Buildings
Authors: Vojtekova Eva
Published: January 2016

Since the period of application curtain wall on skeleton buildings, small single–storey buildings are the great topic for architects. By various means architects have effort to create an impression of floating roof structure, or an illusion of levitating roof over the country. The effect of transparent space, overlapping interior and exterior, is possible to achieve by use of various structural schemes and materials of support structure. Nowadays single-storey transparent buildings are regarded as a phenomenon, which presents progress in architecture from the point of dematerialization of support structures and details of secondary transparent structures. Glass is in contemporary transparent curtain walls used not only as a material of the building skin, but also as the material of the support structure in various structural elements within hierarchy of the load bearing structure. Flat glass sheets forming the building skin could be within the suitable chosen shape of enclosed envelope also load bearing structure.
Water Supply for Cooling Tertiary Containments for High Storage Tanks
Authors: Kadlec Zdeněk , Kvarčák Miloš , Thomitzek Adam , Trčka Martin
Published: January 2016

This paper presents a numerical investigation of water supply for cooling tertiary containment wall. These type of tanks are used as a part of petroleum high storage tank. Minimum quantity reasonably needed is perform by heat – balance equation. The calculation in is done for the most heat stressed wall part for a case when neighbouring tank is on fire.
Escape Route Typology
Authors: Mikolai Imrich , Tkáč Ján
Published: January 2016

Escape route in the building is the fundamental prerequisite of safe escape in the part of building, or in the whole building. The personnel get away using the escape routes of different quality. The start point of escape is usually on unprotected escape routes that ideally flow directly to exterior.
If it is not possible to eventuate the unprotected escape route directly to free exterior, it must open up into higher quality escape route. That means the persons go to partly-protected escape route or to protected escape route. The dimensions of escape route must verify at least required base typological demands, outgoing from real dimensions of the human body and must also make provision for barriers on them.
Inaccuracies Caused by Non-Uniform Luminance Distribution of Artificial Sky Dome at Scale Model Measurements
Authors: Kondáš Kristián , Darula Stanislav , Lopušniak Martin
Published: January 2016

The primary objective of daylighting measurements, by means of physical models, is the experimental finding of daylight conditions in the interior (in case of scale model of a specific room), or their impact on the surrounding buildings (in case of models of whole buildings). If these measurements are carried out even at the early stage of the building design, they can be very helpful in revealing gross deficiencies of the design or optimization of window apertures. According to the purpose of the measurement, physical models can be placed either on site of the future building – which advantage is the possibility of a reliable reproduction of the actual shading conditions, respectively the amount of reflected light by the envelop of existing buildings – or in laboratory, under artificial sky. The advantage of measurements using artificial skies is mainly the possibility to imitate the conditions of CIE overcast sky, thus the disadvantages of the variability of natural daylight are eliminated, while there is also a potentiality to optimize different solutions at the same boundary conditions. On the other hand, if the luminance distribution of the artificial sky is does not correspond with the theoretical luminance distribution of CIE overcast sky, the results of the measurements can be incorrect. The aim of this contribution is to illustrate through a case study, the importance of ensuring the appropriate boundary conditions at scale model measurements.
The Use of Simulation Tools in the Assessment of External Stationary Sources in Terms of Noise
Authors: Dlhý Dušan , Tomašovič Peter
Published: January 2016

The article is focused on the application of the simulation program to calculate the predicted noise levels from a stationary noise source. These findings are particularly important in the case of protected buildings in category II. According to the Health Ministry Decree No. 549/2007 of the Laws. It gives a concrete solution by simulation program CADNA A, for the purposes of noise study.
Reflection on Modernization of Historic Religious Architecture - Case Study: The Roman Catholic Parish Church, Rajec in Slovakia
Authors: Polomová Beata , Vargová Andrea
Published: January 2016

The historic churches renovation in Slovakia actively served to the religious cult, progressively responds to the gain of new function. It is the use of culture, such as concerts, exhibitions, guided tours. Within a renovation, historic buildings need to be modernized, especially their technical equipment. In this paper we explore a case study of the church restoration in the town Rajec in the north - western Slovakia. It is registered in the list of monuments. We focused on the monitoring of the building construction design which may affect the preservation and presentation of cultural historic values (windows, floors, ventilation, illumination, electro-acoustical amplification system). We concluded that demanding procedures for authentic restoration make sense, especially for the preservation of regional cultural and historical values.
Geometric Tolerance Verification - Innovative Evaluation of Facade Surface Flatness Using TLS (Terrestrial Laser Scanning)
Authors: Funtik Tomas , Dubek Marek , Erdelyi Jan
Published: January 2016

This article assesses the application of TLS when evaluating the façade surface flatness on finished facade. Current methods of geometrical tolerance verification are reviewed and the results are compared data obtained from point clouds (using TLS).The process of currently used methods consist of manual verification of flatness by spirit level in accordance with national standards, which specifies exact places to be assessed and the number of measurements. With TLS technology we assess the surface quality and flatness more precisely, faster and moreover, investigate 100% of area. This may lead to better evaluation of the relative position of investigated areas, points and constructions. However, a further investigation, which would define the methodology for evaluation the geometric tolerance from point clouds is needed.
Strain-Rate Sensitivity Enhanced by Grain-Boundary Sliding in Creep Condition for AZ31 Magnesium Alloy at Room Temperature
Authors: Matsunaga Tetsuya , Somekawa Hidetoshi , Hongo Hiromichi , Tabuchi Masaaki
Published: January 2016

This study investigated strain-rate sensitivity (SRS) in an as-extruded AZ31 magnesium (Mg) alloy with grain size of about 10 mm. Although the alloy shows negligible SRS at strain rates of >10-5 s-1 at room temperature, the exponent increased by one order from 0.008 to 0.06 with decrease of the strain rate down to 10-8 s-1. The activation volume (V) was evaluated as approximately 100b3 at high strain rates and as about 15b3 at low strain rates (where b is the Burgers vector). In addition, deformation twin was observed only at high strain rates. Because the twin nucleates at the grain boundary, stress concentration is necessary to be accommodated by dislocation absorption into the grain boundary at low strain rates. Extrinsic grain boundary dislocations move and engender grain boundary sliding (GBS) with low thermal assistance. Therefore, GBS enhances and engenders SRS in AZ31 Mg alloy at room temperature.
Effect of Solute Elements on Grain Refinement during Friction Stir Processing in High-Purity Aluminum
Authors: Uesugi Tokuteru , Iwami Hideaki , Takigawa Yorinobu , Higashi Kenji
Published: January 2016

Friction stir processing (FSP) is one of the severe plastic deformation (SPD) processes. It has been reported that SPD-processed Al with various purities attained a minimum grain size when Zener-Hollomon parameter is larger than 1016 s-1. The minimum grain size is different by purity level and alloying elements. We investigated the influence of Fe solute atoms on grain refinement of high-purity Al on the condition that Zener-Hollomon parameter was larger than 1016 s-1. FSP was conducted on Al-0.01%Fe, which was fabricated by using 5N Al (99.999% purity). FSP-ed Al-0.01%Fe exhibits the minimum grain size of 1.4 μm, although high-purity aluminums with more than 99.998% exhibits much larger minimum grain sizes of 30-40 μm. Only 101 at.ppm Fe played a critical role in the grain refinement of pure aluminums.
Enhanced Plasticity of Pure Nickel Processed by HPT Consolidation of Rapid Quenched Ribbons
Authors: Zhilyaev Alexander P.
Published: January 2016

Although superplasticity has intensively been studied for half century, few observations have been reported for pure metals due to fast grain growth at temperatures required for superplasticity. With developing of nanocrystalline materials, there was a hope that superplasticity could be obtained in a number of pure metals. Indeed, low temperature superplasticity in pure nickel was reported in pioneering work in 1999, later superplastic feature of nanonickel was attributed to sulfur presence in grain boundaries. Recently, it was concluded that superplasticity it is not related to the presence of sulfur at grain boundaries or a liquid phase at grain boundaries. Thereby, the phenomenon of superplasticity in pure metals is still far away for our understanding and it requires future work. This report is devoted to reassessment of superplastic behavior of nanonickel and it provides new results on enhanced plasticity of pure nickel processed by HPT consolidation of rapid quenched ribbons.
Research on Superplasticity of Supplied 5A06 Aluminium Alloy Sheet
Authors: Bi Bao Peng , Wang Yong
Published: January 2016

Superplasticity of supplied 5A06 aluminum alloy is reviewed in this paper. Supplied 5A06 aluminum alloy is researched on superplasticity by the methods of same strain rate high temperature uniaxial tensile tests at temperature range375°C-500°Cand strain rate range 2.5×10-4s-1~1.0×10-2s-1. Microstructure and fracture of tensile samples are analyzed and discussed, deduce that grain boundary sliding (GBS) is the predominant deformation mechanism. Superplastic formability of the alloy is evaluated by gas bulging test at elevated temperatures. Gas bulging test demonstrates the deformation process parameters for the best superplastic formability is 400°Cand 0.005s-1 ,suggesting good application prospect for this aluminum alloy.
Superplasticity of Metallic Alloys: Some Current Findings and Open Questions
Authors: Blandin Jean Jacques
Published: January 2016

Superplasticity of metallic alloys has been widely investigated for many years but despite numerous studies, some important questions regarding superplastic behavior of metals can be considered as still open. Among others, one can mention the role of grain boundary sliding as contributing mechanism of deformation, the microstructural requirements for getting superplasticity in metallic alloys or the link between mechanisms of deformation and mechanisms of damage. Interesting information were recently obtained by the use of new experimental techniques. One can mention for instance the development of fine grids allowing more detailed studies of the respective contributions of intra-and inter-granular strains in superplastic alloys or fast X-ray micro tomography allowing in situ 3D damage studies. The aim of this paper is to give information about current findings related to superplastic deformation of metallic alloys and to suggest some perspectives for future.
High-Temperature Plasticity in Super Hard Boron Carbide Ceramics
Authors: Moshtaghioun Bibi Malmal , Gómez-García Diego , Domínguez-Rodríguez Arturo
Published: January 2016

Boron carbide-based ceramics will be probably the most promising materials during the next decades due to their excellent mechanical properties combined with its chemical stability and low-density. Boron carbide itself is a very challenging system because of its complicated but highly-symmetrical crystallographic structure. Room-temperature mechanical properties of pure boron carbide have deserved considerable attention due to its remarkable hardness and resistance to shock-impact; however, its high-temperature plasticity with unsual ductility remains unexplored. The high-temperature creep of pure B4C polycrystals and the microsturctural observation were performed to find the mechanism of deformation in this material.
Thermo-Mechanical Modeling of Distortions Promoted during Cooling of Ti-6Al-4V Part Produced by Superplastic Forming
Authors: Rollin Maxime , Velay Vincent , Penazzi Luc , Pottier Thomas , Sentenac Thierry , Iranzo-Perez Laura , Dupuy Alain , Khelifati Gaël
Published: January 2016

In AIRBUS, most of the complex shaped titanium fairing parts of pylon and air inlets are produced by superplastic forming (SPF). These parts are cooled down after forming to ease their extraction and increase the production rate, but AIRBUS wastes a lot of time to go back over the geometric defects generated by the cooling step. This paper investigates the simulations of the SPF, cooling and clipping operations of a part on Abaqus® Finite element software. The different steps of the global process impact the final distortions. SPF impacts the thickness and the microstructure/behavior of material, cooling impacts also the microstructure/behavior of material and promotes distortions through thermal stresses and finally, clipping relaxes the residual stresses of the cut part. An elastic-viscoplastic power law is used to model material behavior during SPF and a temperature dependent elastic perfectly plastic model for the cooling and clipping operations.
Chronicling the Development of a High Strength 5xxx-Based Superplastic Aluminium Alloy
Authors: Miller-Jupp Simon Peter
Published: January 2016

In recent years there has been a largely unspoken demand for a high strength, non-heat treatable aluminium alloy for superplastic forming applications. This is particularly true for the automotive industry since the high strength, superplastic aluminium alloys, such as AA7475, are both too time consuming (in forming and heat treatment) and too expensive. Compound this with the expense of corrosion protection and almost all aluminium alloys except for AA5083 fall by the wayside for the automobile industry.However, the need for a higher strength alloy has remained. To achieve this Hydro has systematically investigated the basis behind the superplastic forming of AA5083. On this basis a new high strength 5xxx alloy was extrapolated. The resulting alloy was then characterised and benchmarked against the existing SPF alloy, AA5083. The new alloy, an AA5456-type alloy demonstrated a higher strength than AA5083 while improving the formability and rate of forming. This paper will discuss some of the lessons learned during the development of this alloy.
Influence of Second-Phase Particles on the Hot Ductility of Al–Mg Solid-Solution Alloys
Authors: Ito Tsutomu , Kawasaki Kentaro , Mizuguchi Takashi
Published: January 2016

Class-I or Class-A solid solutions are substitutional with a relatively large difference in size between the solute and solvent atoms. High-temperature deformation of these solid solutions causes uniform transgranular deformation because of the solute drag motion of dislocations. Consequently, enhanced ductility can be obtained regardless of grain size. In our research, we specifically investigated the effects of second-phase particles resulting from adding impurity atoms on the hot ductility; i.e., how the second-phase particles obstruct the solute drag motion of dislocations. In this study, the effect of Mn and Cr impurities on the high-temperature ductility of typical Class-I Al−Mg solid solutions is investigated. The results show that hot ductility in the basic Al−Mg alloy leads to an elongation to fracture of above 200% at 673 and 723 K. We found that the dominant deformation mechanism causing high ductility is solute drag creep. The hot ductility decreases when Cr is added to the basic alloy, but an elongation to fracture of above 200% can still be achieved by adding Mn, although the elongation is less than that of the basic alloy.
Elimination of Shrinkage Cavities by Liquid Hot Isostatic Pressing in Aluminum Alloys under Superplastic Conditions
Authors: Tagirov Damir , Kaibyshev Rustam
Published: January 2016

The liquid hot isostatic pressure in superplastic conditions was applied to eliminate macroporosity in a die cast Al-12%Si eutectic alloy. The removing of macroporosity provides the yield stress increase of 56%, the ultimate tensile strength increase of 46%, the total elongation increase of 21%, the fracture toughness increase of 340% and the fatigue strength increase of 58%. Remarkable improvement of mechanical properties is caused by suppression of crack initiation on internal coarse pores.
Severe Plastic Deformation under High Pressure for Production of Superplastic Materials
Authors: Horita Zenji
Published: January 2016

Grain refinement is an important prerequisite for advent of superplasticity. In particular, as the grain size is smaller, the superplasticity appears at higher strain rates and lower temperatures. Severe plastic deformation (SPD) is a useful process for achieving significant grain refinement. This presentation shows that applicability of the SPD process is enhanced when it is operated under high pressure through high-pressure torsion (HPT) and high-pressure sliding (HPS). It is demonstrated that commercially available conventional alloys but less ductile alloys such as Mg alloys, age-hardenable high-strength Al alloys (A2024, A7075) and Ti alloys become superplastic after processing by HPT or HPS.
Production, Properties and Application of Ultrafine-Grained Titanium Alloys
Authors: Zherebtsov Sergey , Salishchev Gennady
Published: January 2016

Some features ofstructure, way of production and mechanical properties of titanium andtwo-phase titanium alloys with ultrafine-grained (UFG) microstructure werediscussed. Various methods of UFG structure formation was considered andoptimal conditions for attaining of a homogeneous microstructure with thesmallest grain size were determined. The kinetics of microstructure evolutionin titanium and two-phase titanium alloys during large (severe) plasticdeformation in a wide temperature interval and the mechanisms of ultrafinegrain formation were analyzed. The influence of grain size on static mechanicalproperties was determined. Significantly reduced temperatures of superplasticforming of the UFG conditions were shown. Some examples of practical applicationsof the UFG two-phase titanium alloys were discussed.
Mechanical Behavior and Microstructure Evolution during Superplastic Deformation of the Fine-Grained AlCoCrCuFeNi High Entropy Alloy
Authors: Stepanov Nikita , Shaysultanov D.G. , Salishchev Gennady A. , Senkov O.N.
Published: January 2016

Characteristics of mechanical behavior during superplastic flow and associated microstructural evolution in the wrought AlCoCrCuFeNi high-entropy alloy were studied. The alloy had complex microstructure with fine grain/particle size of ≈2.1 μm. 4 different phases with volume fractions from 7% to 46% and different deformation characteristics were found in the alloy. Very high tensile elongations of up to 1240% were observed during deformation at temperatures of 800°C–1000°C and at strain rates of 10-4 s-1–10-1 s-1 despite presence of pronounced softening stage followed by steady state flow stage. Microstructure of the alloy after tensile testing was studied in detail. Phase transformations were analyzed employing thermodynamic modeling and their role in strain accommodation is discussed.
Nanostructurization of Magnesium Alloy via Friction Stir Lap Processing
Authors: Kimoto Yoshihisa , Nagaoka Toru , Watanabe Hiroyuki , Fukusumi Masao , Morisada Yoshiaki , Fujii Hidetoshi
Published: January 2016

Friction stir processing (FSP) in a lap configuration of a metal sheet and an alloy plate has been examined to produce surface alloy layer with nanostructures. The 1-pass friction stir lap processing (FSLP) over 0.5 mm-thick Cu sheet on an AZ91 substrate produced multilayer structure with nanograins and/or nanoprecipitates in each layer, but the structure distributed only partially in the stir zone (SZ). Through the 3-pass FSLP along the same line, the multilayer structure has disappeared and the fine structure with precipitates in size ranging from several 100 nanometer to 3 micrometer has yielded among the entire SZ. 2-dimensional microhardness mapping have shown that the standard deviation of microhardness values in the SZ has decreased by half from 1-pass to 3 pass FSLP. Homogeneous microstructure involving nanostructures has been successfully produced via multi-pass FSLP.
Superplastic Behavior of an AA2139 Subjected to ECAP
Authors: Gazizov Marat , Kaibyshev Rustam
Published: January 2016

An AA2139 alloy belonging to Al-Cu-Mg-Ag system was subjected to thermomechanical processing (TMP) included solution treatment at 525°C for 1 h, quenching in water, over-aging at 380°C for 3 h followed by equal-channel angular pressing (ECAP) at 250°C to a total strain of ~12 via route BC. This TMP produced a partially recrystallized structure with fine crystallites having an average size of ~0.9 μm and a fraction of high-angle boundaries of ~56%. Tensile test was performed in the temperature interval 300-500°C at initial strain rates ranging from ~1.8×10-4 to ~1.7×10-1 s-1. It was shown that the highest elongation-to-fracture of ~660% appears at a temperature of 400°C and an initial strain rate of 1.4×10-3 corresponding with the coefficient of sensitivity coefficient, m, of 0.34.
Submicrocrystalline Austenitic Stainless Steel Processed by Cold or Warm High Pressure Torsion
Authors: Tikhonova Marina , Enikeev Nariman , Valiev Ruslan Z. , Belyakov Andrey , Kaibyshev Rustam
Published: January 2016

The formation of submicrocrystalline structure during severe plastic deformation and its effect on mechanical properties of an S304H austenitic stainless steel with chemical composition of Fe – 0.1C – 0.12N – 0.1Si – 0.95Mn – 18.4Cr – 7.85Ni – 3.2Cu – 0.5Nb – 0.01P – 0.006S (all in mass%) were studied. The severe plastic deformation was carried out by high pressure torsion (HPT) at two different temperatures, i.e., room temperature or 400°C. HPT at room temperature or 400°C led to the formation of a fully austenitic submicrocrystalline structure. The grain size and strength of the steels with ultrafine-grained structures produced by cold or warm HPT were almost the same. The ultimate tensile strengths were 1950 MPa and 1828 MPa after HPT at room temperature and 400°C, respectively.
Superplastic Behavior of a Cu-Cr-Zr Alloy Subjected to ECAP
Authors: Mishnev Roman , Shakhova Iaroslava , Belyakov Andrey , Kaibyshev Rustam
Published: January 2016

A Cu-0.87%Cr-0.06%Zr alloy was subjected to equal channel angular pressing (ECAP) at a temperature of 400 °C up to a total strain of ~ 12. This processing produced ultra-fine grained (UFG) structure with an average grain size of 0.6 μm and an average dislocation density of ~4×1014 m-2. Tensile tests were carried out in the temperature interval 450 – 650 °C at strain rates ranging from 2.8´10-4 to 0.55 s-1. The alloy exhibits superplastic behavior in the temperature interval 550 – 600 °C at strain rate over 5.5´10-3 s-1. The highest elongation-to-failure of ~300% was obtained at a temperature of 575 °C and a strain rate of 2.8´10-3 s-1 with the corresponding strain rate sensitivity of 0.32. It was shown the superplastic flow at the optimum conditions leads to limited grain growth in the gauge section. The grain size increases from 0.6 μm to 0.87 μm after testing, while dislocation density decreases insignificantly to ~1014 m-2.
About Formability of Ultra-Fine Grained Metallic Materials
Authors: Sabirov Ilchat , Moreno-Valle Eva , Murashkin Maxim Yu. , Valiev Ruslan Z.
Published: January 2016

Ultra-fine grained (UFG) and nanostructured metallic materials obtained via severe plastic deformation typically show very high mechanical strength but low tensile ductility, which dramatically limits their practical utility. Significant efforts were made to improve uniaxial tensile ductility of ultra-fine grained and nanostructured metallic materials. The developed strategies can be divided into two main groups. (1) The ‘mechanical’ strategies employ the mechanical characteristics of these materials, such as their work hardening ability and/or strain rate sensitivity. These mechanical characteristics can be varied via changing testing parameters, such as temperature and/or strain rate. (2) The ‘microstructural’ strategies are based on idea of intelligent microstructural design to suppress necking at early stages of plastic deformation thus improving ductility. However, not much attention was paid to the fact, that in metallforming operations, metallic materials are not deformed uniaxially, but have to undergo deformation under complex strain paths. This work aims to demonstrate that despite UFG metallic materials have low tensile ductility, they can show enhanced formability during plastic deformation in complex stress state (such as formability under biaxial stretch, which is sufficient for metalforming operations.
Superplastic Forming of a Complex Shape Automotive Component with Optimized Heated Tools
Authors: Sorgente Donato , Palumbo Gianfranco , Scintilla Leonardo Daniele , Brivio Riccardo , Carozzi Gabriele , Tricarico Luigi
Published: January 2016

Superplastic forming (SPF) commonly requires industrial presses with an integrated large furnace able to uniformly heat the tools and the blank. In this work the feasibility to form via SPF an automotive component using a different heating approach was investigated. The heat is localized only where it is really needed embedding electric heating elements directly in the forming tools. Preliminary numerical simulations of the heating phase were aimed at calculating the electrical power and at choosing a suitable positioning of the heating elements. Further forming simulations were run to calculate the pressure profile. SPF experiments were finally conducted and sound components were obtained saving energy costs and using a common industrial press with lower investment costs.
Efficient Diffusion Bonding of Large Scale Parts
Authors: Jahn Simon , Gemse Felix , Broich Udo , Saendig Sabine
Published: January 2016

Worldwide there is a trend to use diffusion bonding for more and more applications, for example for large scale micro channel heat exchangers and heat sinks. For large scaled parts there is only a limited range of systems commercially available today. One most important criterion for large scale diffusion bonding is a homogeneous load distribution. To achieve this, different concepts can be used, e.g. multiple supports around pressing plates or using very thick pressing plates. In the presentation an overview of bonded examples, made of different materials, is given as well as a detailed description of the used diffusion bonding systems. In addition, the methods for characterization of the systems and bonded parts are included as well.
Research on Work Hardening Type Superplastic Deformation Behavior of FSW Titanium Alloy
Authors: Fu Ming Jie , Li Xiao Hua , Han Xiu Quan , Xu Hui Yuan
Published: January 2016

The combination of FSW and SPF processing is one of most attractive fabrication method for the larger structures and integrate substructure to reduce the part count of aircraft assemblies and costs. One purpose of the SPF technology development is to decrease the forming temperature and increase the forming rate, then reduce cost and enhance the efficiency. Maybe FSW could supply another way to achieve this besides reduce the grain size by traditional rolling process. The purpose of this study is to indicate some new results of the superplasticity of weld nugget for the Ti-6Al-4V alloy. It is found that the temperature has no much effects on the superplastic tensile elongation of the weld nugget, and deformation rate has the contrary effects on the superplasticity to the traditional results, the elongation will be higher with the higher deformation rate. The mechanism will be discussed with the analysis of the microstructure by SEM. The tensile properties was tested after SPF process with a 60% strain.
Formabilities of C-Si-Al-Mn Transformation-Induced Plasticity-Aided Martensitic Sheet Steel
Authors: Kobayashi Junya , Nakashima Yumenori , Sugimoto Koh Ichi , Itoh Goroh
Published: January 2016

The substitution of Si with Al in 0.2%C-1.5%Si-1.25%Mn-0.2%Cr ultrahigh strength transformation-induced plasticity (TRIP)-aided martensitic (TM) sheet steel improves galvanization. The effect of Al content on the microstructure and formabilities of the TM steel was therefore investigated. Replacement of Si with Al maintained the high volume fraction of the retained austenite and the high stretch-formability and stretch-flangeability, whereas it decreased the tensile strength. Complex addition of Si and Al yielded the best formabilities with 1.5 GPa tensile strength grade. The superior formabilities of Si-Al bearing TM steel were attributed to the strain-induced transformation of the metastable retained austenite and the relatively soft lath-martensite structure matrix. The former leads to plastic relaxation of the localized stress concentrations, thus suppressing void formation.
Characterization of Superplastic Materials by Results of Free Bulging Tests
Authors: Aksenov Sergey A. , Zakhariev Ivan Y. , Kolesnikov Aleksey V. , Osipov Sergey A.
Published: January 2016

Determination of material constants describing its behavior during superplastic gas forming is the main subject of this study. The main feature of free bulging tests is the stress-strain conditions which are very similar to ones occurring in the most of gas forming processes. On the other hand, the interpretation of the results of such tests is a complicated procedure. The paper presents a simple technique for the characterization of materials superplasticity by free bulging tests, which is based on inverse analysis. The main idea of this technique is a semianalytical solution of the direct problem instead of finite element simulation which allows one to reduce the calculation time significantly. At the same time the results this simplified solution are accurate enough to obtain realistic material constants.
Superplastic Behavior of ATI 718Plus Superalloy
Authors: Mukhtarov Shamil Kh. , Utyashev Farid Z.
Published: January 2016

Complex shaped, ultra thin-walled parts can be manufactured using superplastic forming. Hot working temperature for the production of fine-grained billets (d=5-15 μm) out of ATI Allvac 718Plus® superalloy is in the range of 982-1038°C. An ultrafine-grained structure (d=0.3 μm) was produced by multi-axial forging with a gradual decrease of the forging temperature from 950 to 700°C. Superplastic properties of the alloy were carried out in the temperature interval of 700-950°C. It has been revealed that the fine-grained alloy provided superplastic elongations about 300% at 950°C and strain rate of 10-4 s-1. The highest elongation of ultrafine-grained alloy was about 1450% and very low flow stresses were reached at 900°C and strain rate of 3×10-4 s-1. The ultrafine-grained alloy showed superplastic properties also at 700°C (0.62Tm). The microstructure and superplastic properties of the alloys 718 and 718Plus are compared.
Production of a Superplastic Vibration-Damping Steel Sheet Composite Using Friction Stir Forming
Authors: Mofidi Tabatabaei Hamed , Hara Takahiro , Nishihara Tadashi
Published: January 2016

This study proposes a novel method of manufacturing composite vibration-damping steel sheet with Zn-22Al superplastic alloy using friction stir forming (FSF). Trials of mechanical interlocking of steel sheet with Zn-22Al superplastic alloy using FSF were carried out on a modified milling machine. The results are discussed in terms of residual microstructures and mechanical properties. We concluded that cladding steel sheet with Zn-22Al superplastic alloy using FSF results in superplastic forming and diffusion bonding.
Texture Change during Superplastic Deformation in Fine-Grained Magnesium Alloys
Authors: Watanabe Hiroyuki , Uesugi Tokuteru , Takigawa Yorinobu , Higashi Kenji
Published: January 2016

Texture change during superplastic deformation was examined and compared in two magnesium alloys with different chemical composition. These alloys were extruded to refine the microstructure. The pre-existing basal texture of both alloys became slightly more random within the bulk probably owing to grain boundary sliding and the accompanying grain rotation. However, the texture changes differed between tensile and compressive deformation along the extrusion (longitudinal) direction. This fact suggests that dislocation slip is important in superplastic deformation. It was concluded that dislocation slip acts primarily as an accommodation mechanism for grain boundary sliding.
Study on the Potential of Kaolinitic Clay from Perak State, Malaysia for Aluminosilicate Ceramic Ball
Authors: Yahya Hamdan , Othman Mohd Roslee , Ahmad Zainal Arifin
Published: January 2016

Commercially made kaolin is identified as one of the important materials for production of aluminosilicate for catalyst bed support. In this work, an attempt is made to study the potential of local clay for production of aluminosilicate. Three area were identified as kaolin sources in Perak state as they are Trong, Simpang Pulai and Bidor, and labelled as TC, SP and BC, respectively. For preparation of aluminosilicate, formulation using 30% clay and the rest used feldspar (40%) and silica sand (30%). Each batch were formed into ball shapes’ before fired at 1250°C at controlled firing rate of 3°C/min. From the investigation, it is found that only two local clays (CBTC and CBSP) highly potential to be used to produce ceramic ball for catalyst support. In addition, the crushing strength is 100% better than the commercial made product which also have less than 1% water absorption.
Titania (TiO2) as Antibacterial Material in Ceramic Tiles: Effect of Composition
Authors: Mohamad Hasmaliza , Shian Foo Hui , Mokhtar Ahmad Kamil Fakhruddin
Published: January 2016

Titania (TiO2) is one of a common and favorable material use in the manufacturing industry due to its uniqueness and functional performances to human and environment. The study was focused on the performance of glaze added TiO2 (anatase phase) in the application of porcelain tiles. Anatase powder in micro size was used (varies at 5 wt%, 10 wt % and 15 wt%) to observe their performance as antibacterial materials. The anatase powders were mix into the glaze composition and apply to the porcelain tile through dip coating. The viscosity of each composition was observed to study their effect. Characterization used to observe the properties of anatase mixed glazed porcelain tile were X-ray diffraction (XRD), Scanning electron microscopy (SEM) and antibacterial test. The results shown that higher composition of anatase powder, viscosity of the mixed glaze is higher and a rougher surface of glazed tiles was formed. XRD result shows that the higher the composition is more the intensity of TiO2 on the glaze coating surface, supported by SEM results. Antibacterial testing towards E.Coli was observed by counting the colonies of bacterial growth in 0 hr, 2 hrs, 4 hrs and 8hrs. The antibacterial properties increase when the composition of anatase increases.
Influence of Calcination Temperature on the Microstructure and Crystallographic Properties of Hydroxyapatite from Black Tilapia Fish Scale
Authors: Ahmad Fara Ahmad Norman Khalis , Abdullah Hasan Zuhudi
Published: January 2016

Hydroxyapatite extensively used for orthopaedic and dental reconstruction as biomaterials due to their chemical and biological similarity to human hard tissue. Therefore, this paper describes the extraction of natural hydroxyapatite from tilapia fish scale via a conventional heat treatment. The calcination temperatures (600, 800, 1000, and 1200°C) were varied. XRD results indicated that the presences of biphasic phase (HA/β-TCP) were identified during heat treatment. Transformation of biphasic phase to single phase (β-TCP) can be observed at 1200°C, results on decomposition of hydroxyapatite. The degree of crystallinity and crystallite size originated increase with the calcination temperature. The FT-IR spectra confirmed that all organic compounds were eliminated during the heat treatment process. FESEM images were used to determine the size and shape of grains of calcined samples. The biphasic mineral grain size was estimated in range of 500 – 100 nm. The analysis show that variation of calcination temperatures significantly impact on the properties of hydroxyapatite derived from tilapia fish scale.
Effects of Hydrochloric Acid Concentration on the Properties of Black Tilapia Fish Skin Gelatin
Authors: Ismail Norhasikin , Abdullah Hasan Zuhudi
Published: January 2016

Gelatin extractedfrom fish skin is an alternativeresource instead of mammalian animals. Theextraction process of gelatin from black tilapia skin was carried out throughthe use of hydrochloric acid (HCl) with different concentration (0.05 M – 1.0 M)and followed by a final extraction with water at 50°C for 4 hours and endedwith drying. Characterization of gel strength was done in accordance with BSI:1975while moisture content and percentage yield on wet basis with AOAC 1999. Theeffects of acid concentration used during pre-treatment process on yield andphysical properties of fish gelatin were measured. The yield of gelatin for0.05 M and 1.0 M were 10.45% to 22.25% respectively. The gel strength ofgelatin at 0.05 M is the highest (833 g) due to longer storage time. Gelatin whichtreated with high acid concentration gives lower in gel strength that suitableas an edible gelatin.
Effect of Bath Temperature on Surface Properties of Anodised Titanium for Biomedical Application
Authors: Lee Te Chuan , Mazlan Mohd Hafifi Hafizat , Abbas Mohamad Imran , Abdullah Hasan Zuhudi , Idris Maizlinda Izwana
Published: January 2016

Anodic oxidation is an electrochemical method to deposit ceramic coatings on the metals substrate to improve the bioactivity. This study aims to investigate the effect of bath temperature on the surface properties of anodised titanium. High-purity titanium foil was modified by anodising in mixture of β-glycerophosphate disodium salt pentahydrate (β-GP) and calcium acetate monohydrate (CA). The experiments were carried out at 350 V, 30 mA.cm-2 for 10 minutes at different bath temperature (4-100 °C). Field emission scanning electron microscopy (FESEM), glancing angle X-ray diffractometer (GAXRD) and goniometer were used to characterise the surface morphology, mineralogy and wettability of anodised titanium, respectively. The results showed that porosity and crystallinity of surface decreased as increasing of bath temperature. Interestedly, the α-tricalcium phosphate (α-TCP) was deposited on the samples which anodisation at higher bath temperature (≥ 60 °C) and resulted high hydrophilicity behaviour even the surface was found relatively smooth.
Effect of Using Different Compositions and PU Foam Template to Produce Cobalt Chromium Molybdenum (CoCrMo) Foams
Authors: Abdul Manaf Nur Suliani , Ahmad Sufizar , Ibrahim Rosdi
Published: January 2016

Slurry dipping is a simple and popular method of producing porous and interconnected foams using a metallic slurry. The advantage of the network-like metal foams is it exhibits a natural bone-like structure which enables ingrowth of bone cells and blood vessels. The aim of the present study was to investigate the effect of using difference composition and scaffold to produce Cobalt Chromium Molybdenum (CoCrMo) foams. The CoCrMo slurry was prepared by using different composition of CoCrMo powder which was 60wt%, 65wt% and 70wt%. Also two different types of scaffold were used in this study. The CoCrMo slurry was produced by mixing CoCrMo powder with Polyethylene Glycol (PEG), Carboxyl Methyl Cellulose (CMC) and distilled water. Then, polyurathane foam template was dipped in CoCrMo slurry and dried at room temperature. Sintering process was running by vacuum furnace at high temperature, 1200°C. The CoCrMo foam was characterized by using a Scanning Electron Microscopy (SEM) analysis. The physical properties of CoCrMo foam was analyzed by porosity and bulk density test that was Archimedes method. From the study it was expected that the composition of metallic slurry play important roles to produce a CoCrMo foam. In order to orthopaedics application to apply in cancellous bone, highest value of porosity from PU foams type (a) was most suitable result to use. This is due to the value of porosity that generate that was 65.2%.
Preparation of Bioactive Titanium Film via Anodic Oxidation in Agitation Condition
Authors: Lee Te Chuan , Mazlan Mohd Hafifi Hafizat , Abbas Mohamad Imran , Abdullah Hasan Zuhudi , Idris Maizlinda Izwana
Published: January 2016

Anodic oxidation is a well-established surface modification method which combines electric field driven metal and oxygen ion diffusion to produce protective oxide layer on metals. This method has been widely used to modify the surface properties of titanium and its alloy. This present study aims to investigate the effect of agitation speed on the surface properties of anodised titanium. At first, the high purity titanium foils were anodised in mixture of 0.04 M β-glycerophosphate disodium salt pentahydrate (β-GP) and 0.4 M calcium acetate monohydrate (CA) at 350 V and 30 mA.cm-2 for 10 minutes at different agitations speed (300 rpm - 1500 rpm). Next, surface properties of anodised titanium were characterised by digital single-lens reflex camera (DSLR camera), field emission scanning electron microscopy (FESEM) and glancing angle X-ray diffractometer (GAXRD). At lower agitation speed (≤ 900 rpm), surface of anodised titanium covered by small donut-shaped pores. With increasing of agitation speed (≥ 1100 rpm), the oxide layer became more porous and covered by larger donut-shaped pores. Rutile TiO2 peaks were detected at agitation speed more than 1100 rpm. Agitation condition is believed to be an effective method to enhance the surface properties of anodised titanium for biomedical applications.