bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparative Bioreduction of Fe(III) with Geobacter metallireducens and Bacillus infernus
Authors: Crespo Javier , Muñoz J.A. , González F. , Blázquez M. Luisa , Ballester Antonio
Published: March 2009

A comparative study on the Fe-reducing ability of pure anaerobic strains of Geobacter
metallireducens and Bacillus infernus was investigated using different sources of Fe(III). Batch
tests were carried out in aqueous solutions containing a reducing agent (lactate or formate) and at a
constant temperature of 37°C and 50°C respectively. The formation of biogenic compounds of
Fe(II) was determined using XRD and SEM-EDX techniques.
The bioreduction of magnetite was not affected by the type of bacterial strain used. The kinetics
of the process, initially very fast, stopped rapidly for both types of microorganisms. Vivianite
(Fe3(PO4)2.8H2O) was detected as the main biogenic compound formed during the bioreduction
process.
Sorption of Co Ions on Biogenic Mn Oxides Produced by a Mn-Oxidizing Fungus, Paraconiothyrium sp.-like Strain
Authors: Sasaki Keiko , Matsuda M. , Urata T. , Hirajima Tsuyoshi , Konno H.
Published: March 2009

Sorption of Co(II) on the biogenic Mn oxide produced by a Paraconiothyrium sp.-like strain was investigated. The biogenic Mn oxide, which was characterized to be poorly crystalline birnessite (Na4Mn(III) 6Mn(IV) 8O27 ·9H2O) bearing Mn(III) and Mn(IV) in the structure, showed approximately 6.0-fold higher efficiency for Co(II) sorption than a synthetic Mn oxide. XP-spectra of Co 2p for the biogenic and synthetic Mn oxides after Co(II) sorption indicate that Co was immobilized as Co(III) on the surface of Mn oxides, clearly suggesting that redox reaction occurs between Co(II) ions and each Mn oxides. The Co(II) ions would be initially sorbed on the vacant sites of the surface of biogenic Mn oxide, and then oxidized to Co(III) by neighbor Mn(III/IV) atoms to release Mn(II). For the synthetic Mn oxide, release of Mn(II) was negligibly small because the oxidant is only Mn(IV) in ramsdellite (γ-MnO2). The Mn(II) release from the biogenic Mn oxide during Co(II) adsorption would be not only from weakly bounded Mn(II), but also from redox reaction between Mn(III/IV) and Co(II) ions.
Mercury Sorption on Chitosan
Authors: Campos Karol , Guibal Eric , Peirano Francisco , Ly M. , Maldonado Holger
Published: March 2009

Mercury sorption on chitosan was investigated in batch and continuous systems. Chitosan sorption properties were determined through sorption isotherms. Langmuir and Freundlich equations were used for the modeling of isotherms at pH 5. In batch systems, maximum sorption capacities reached 550 mg Hg/g. Sorption kinetics have been studied as a function of sorbent particle size and stirring rate. Dynamic removal of mercury was tested in a fixed bed reactor investigating the following parameters: particle size, column size, flow velocity and metal ion concentration. Clark and Adams-Bohart models were evaluated for the simulation of breakthrough curves. This study shows that chitosan is an effective sorbent for the treatment and recovery of mercury from dilute effluents at near neutral pH.
Biorecovery of Gold from Jewellery Wastes by Escherichia Coli and Biomanufacture of Active Au-Nanomaterial
Authors: Deplanche K. , Attard G.A. , Macaskie Lynne E.
Published: March 2009

Microbial reduction of Au(III) from HAuCl4 was demonstrated. Escherichia coli and Desulfovibrio desulfuricans reduced 1 mM Au(III) in 60 and 120 min at pH 6.9 and 2.3 respectively. TEM and elemental analysis showed the formation of Au(0) nanoparticles and their pH-dependent cellular localisation. The concept was applied to the recovery of gold from jewellery waste leachates using E. coli. Bio-Au(0) nanoparticles were tested for catalytic activity in the oxidation of glycerol, achieving 30% conversion to glyceric acid. A simple bioprocess for conversion of waste to new material is suggested.
Characterisation of Factors in the Bacterial Leaching of Nickel Laterites Using Statistical Design of Experiments
Authors: Simate Geoffrey S. , Ndlovu Sehliselo
Published: March 2009

Identifying influential factors in the bacterial leaching of nickel laterites using a mixed
culture of chemolithotrophic micro-organisms was explored using the approach of statistical design
of experiments. In a series of experiments, pH, particle size, pulp density, type of substrate and
inoculum size were statistically combined using a quarter fractional factorial designs 2 5−2
III and tested
for their influence on nickel recovery using chemolithotrophic microorganisms. The results
indicated that inoculum size was not statistically significant while the rest of the factors were
statistically significant. Under the ranges studied the interaction between the variables was found to
be weak. The results also showed that recovery was maximized at low pH and low pulp density. In
the range studied, particles of less than 38μm had a negative influence on nickel recovery. Sulphur
substrate also showed better effects than pyrite.
Electrochemical Noise Analysis of Chalcopyrite Carbon Paste Electrodes by Acidithiobacillus ferrooxidans
Authors: Horta Daniela G. , Bevilaqua Denise , Acciari Heloísa A. , Garcia Jr. Oswaldo , Benedetti Assis Vicente
Published: March 2009

The electrochemical response of chalcopyrite was studied using electrochemical noise
analysis (ENA). The assay was carried out under constant aeration using 30 mL in two
electrochemical cells containing iron-free mineral salts solution. These cells were initially
monitored for 56 hours. After 72 hours, 7.25×1010 cells mL-1 of A. ferrooxidans strain LR were
added in both cells and monitored until 128 h. Subsequent to this period, 0.927 mmol L-1 of silver
ions and 400 mmol L-1 of chloride ions were added each one separately. Both conditions were
monitored until 168 hours. According to results obtained, it was observed that Cl- ions addition
induced an accelerated corrosion process. However, there is a tendency of the system to reach the
stationary state due to repassivation of the electrodic surface. In the other side, the Ag+ addition
contributed for the maintenance of the oxidant atmosphere, in spite of controversial effect caused by
considerable variations in the Rn values, resulting in a instability in the chalcopyrite reactivity.
Microbial Leaching of Metals from Printed Circuit Boards
Authors: Willscher Sabine , Katzschner M. , Jentzsch K. , Matys S. , Pöllmann Herbert
Published: March 2009

Electrical and electronic equipment (EEE), e.g. printed circuit boards, contain substantial amounts of metals, e.g. Cu, Pb and Sn. The objective of this work was to investigate the bioleaching of a material, originating from a technical waste processing facility, as one possible way of a complete separation of the metals from the polymer carrier. During the leaching experiments the mechanism of the leaching process was investigated, and biofilms and precipitates were analyzed by microscopical (SEM) and spectroscopical methods (EDX, XRF, XRD). The enhanced formation of exopolymer layers seems to promote the precipitation of secondary mineral particles beneath and the sorption of particles from the suspension on the layer surface.
Low Heat Joining – Manufacture and Fatigue of Soldered Locally Strengthened Structures
Authors: Esderts Alfons , Wesling Volker , Masendorf Rainer , Schram A. , Medhurst Tim
Published: March 2009

The advantages of low heat joining techniques, such as low distortion and little influence
on the local material properties due to the low introduced amount of heat, shall be made usable for
the manufacture of high strength structures by increasing the process reliability. The dependency
between the parameters of the joining process, the seam geometry, the type of solder, the load type
und the fatigue life especially of soldered structure with local strengthening shall be examined to
allow a calculative estimation of the part’s life.
Setting of Gradient Material Properties and Quality Control of High Tension 3D-Weld Joints
Authors: Reimche W. , Bach Friedrich Wilhelm , Duhm Rainer , Mroz G. , Bernard M.
Published: March 2009

Modern metallic materials used in high loading structures are increasingly being placed
under stringent standards with regard to the mechanical strength and deformation properties of their
individual parts as well as with regard to the loading capacity of their junctions. In order to
determine the strain profile of the individual structural components, the mentioned topics will be
taken from the SFB 675 “High tensile, locally manipulated structural components and structures”
from the subproject C4 “Setting of gradient material properties and qualification of high-tension
3D-NVEB weld joints”. To this end, the strengthened individual structural components will be
heated with an electron beam at defined locations. This is done in order to observe the load related
local micro-structure changes and consequently the targeted, structured local changes in the strength
and deformation properties of the material. A delay in the crack growth will also be sought after.
Additionally, components with specifically designed tensile strength will be welded to high quality
structures. At this the young but efficient non vacuum electron beam welding method will be
preferably developed, qualified and used because of its good welding properties regarding to an
improved beam positioning, process control and weld joint defect detection.
Local Effects of Welding Seams with Laser-Based Joining Concepts for High-Strength Load-Transferring Structure Modules
Authors: Schimek Mitja , Meier O. , Ostendorf A. , Engelbrecht L. , Haferkamp H.
Published: March 2009

In subproject B1, local physical and geometrical effects which have only been observed so
far as side effects in the laser joining process, are to be used purposefully, in order to achieve
graded strength properties and to improve the component rigidity significantly. One aim of the work
in the first requested period is the investigation of effects of laser-based joining connections on the
structure rigidity for simplified sample geometries. A defined local strength increase will first be
done on blind seams and later on seams with suitable seam geometries. In the context of SFB 675,
laser joining processes are to be developed further so that the final assembly can take place with
and other methods to increase strength for semi-finished products without considerably changing
the local material characteristics. Beyond that, general rigidity effects of the connections are to be
used purposefully for rigidity improvement.
Development of Combined Manufacturing Technologies for High-Strength Structure Components
Authors: Denkena Berend , Meyer R. , Breidenstein Bernd
Published: March 2009

Novel manufacturing technologies for high-strength structure components of aluminium
allow a local modification of material properties to respond to operational demands. Machining and
finishing processes for changing material properties like deep rolling or rubbing are to be combined
to a single process step. Intention is the controlled modification of the component’s properties by
manipulation of its subsurface. For that purpose the essential understanding of interaction
mechanisms of the basic processes turning, deep rolling and rubbing is necessary. Influences of tool
geometry as well as process parameters on material properties are investigated. The results are to be
extended by parameter studies, done by numerical simulation. Combined processes like “turnrolling”
or “turn-rub-rolling” will be developed.
CAD Model Generation Using 3D Scanning
Authors: Khalili Khalil , Ahmadi-Brooghani Seyed Yousef , Rakhshkhorshid M.
Published: March 2009

3D Scanners are used in industrial applications such as reverse engineering and inspection. Customization of existing CAD systems is one of rapid ways to supplying a 3D Scanning software. In this paper, using AutoLisp and Visual Basic programming languages, AutoCAD has been customized. Also facilities of automatic scanning of physical parts, in the domain of free form surfaces, have been provided. Furthermore, possibilities such as, control of scanner automotive system, representation of registered point clouds, generation of polygon and /or NURBS model from primary or modified point clouds, have been prepared. Triangulation and image processing techniques along with a new fuzzy logic algorithm have been used to extract the depth information more accurate. These, accompanying with AutoCAD capabilities have provided acceptable facilities for 3D scanning.
The Experimental Investigation of the Effects of Different Chip Breaker Forms on the Cutting Forces
Authors: Gürbüz Huseyin , Kurt Adem , Korkut I. , Şeker Ulvi
Published: March 2009

The objective of this paper is experimentally investigation of the effects of different chip breaker forms on the cutting forces according to various cutting parameters. AISI 1050 workpiece material, most used material in the manufacturing industry, and SNMG 120408R inserts and PSBNR 2525M12 tool holder have 75° approaching angle according to ISO 3685 are used in the experiments. Seven groups chip breaker form were used in the tests. The chip breaker forms are the coated inserts MA, SA, MS, GH and standard, and the uncoated inserts MS and standard. These inserts are Mitsubishi UC 6010 and UTI20T grade; correspond to ISO P30 and P15 grade, respectively. Machining tests were carried out by using five levels of cutting speeds (150, 200, 250, 300, 350 m/min), three levels of feed rate (0.15, 0.25, 0.35 mm/rev) and two levels of depth of cut (1.6, 2.5 mm). Cutting forces were measured using Kistler dynamometer. The test results show that the highest cutting force values were measured on SA, GH, MA forms, respectively. Complex chip breaker forms cause the increase of the cutting forces. Although the cutting forces on the uncoated inserts were partly small in light cutting conditions, it has increased on the uncoated inserts in heavy cutting conditions compared to coated inserts.
Corrosion Inhibition of Zinc in KOH Solutions
Authors: Prună Alina , Brânzoi V. , Brânzoi F.
Published: March 2009

The influence of electrolyte additions on the corrosion of zinc in aqueous solutions of
KOH has been determined using electrochemical and nonelectrochemical techniques. These
included anodic and cathodic polarization resistance and potentiodynamic method. The inhibitors
studied included ZnO and tetra-alkylammonium bromides in different concentrations. From the data
provided corrosion currents were calculated. The effectiveness of the inhibitors was compared and
it was found that combinations of zinc oxide with tetra-alkylammonium salts were the most
effective. Surface analysis obtained with scanning electron microscopy (SEM) revealed
morphology characteristics developed at the zinc surface.
Protective Alumina Coatings by Low Temperature Metalorganic Chemical Vapour Deposition
Authors: Şovar Maria Magdalena , Samelor Diane , Gleizes Alain , Alphonse P. , Perisanu S. , Vahlas C.
Published: March 2009

Alumina thin films were processed by MOCVD from aluminium tri-iso-propoxide, with
N2 as a carrier gas, occasional addition of water in the gas phase, deposition temperature in the
range 350-700°C, total pressure 0.67 kPa (2 kPa when water was used). The films do not diffract Xray
when prepared below 700°C. At 700°C, they start to crystallize as γ-alumina. EDS, EPMA,
ERDA, RBS, FTIR and TGA revealed that films prepared in the range 350-415°C, without water in
the gas phase, have an overall composition Al2O3-x(OH)2x, with x tending to 0 with increasing
temperature. Al2O3 is obtained above 415°C. When water is added in the gas phase, the film
composition is Al2O3, even below 415°C. Coatings deposited in these conditions show promising
protection properties.
Mechanical and Corrosion Behaviour of Some Devices for Ostheosinthesis
Authors: Ghiban Brandusa
Published: March 2009

Orthopaedic implants represent mechanical devices which may be used for different purposes in human skeleton. such as either repairing of soft tissues (ligaments) or hard tissues (fractures. osteotomy. partial or total replacements). The aim of present paper is to put in evidence some macro and micro structural features revealed at state of surface after 5 months of implant in a female femoral fracture. Investigated surfaces were analyzed by optical and scanning electron microscopy and by X-Rays diffraction.
Obtaining of Ni Base Intermetallic Alloys by Solidification Control
Authors: Lucaci Mariana , Orban Radu L. , Lazarescu M. , Gavriliu Stefania , Lungu Magdalena , Patroi Delia
Published: March 2009

Directional solidification techniques have been applied to produce Ni based intermetallic
alloys with preferentially oriented columnar crystals extended along the complete length and
parallel to the solidification direction. Enhanced ductility is expected from such alloys. In this paper
we present the research results concerning the application of this technique to some complex Ni3Al-
Fe-B alloys obtained from compacted mixtures of elemental powders. The corresponding master
alloys have been obtained in a vacuum induction furnace by the known Exo-Melt process [1]. The
directional solidification of these alloys was subsequently performed on cylindrical samples, at two
solidification rates, 30 and 15 mm/h. The influence of the rate and composition used on the
dimensional variations, densities, microstructure, constituent phases and lattice parameters, as well
as on the surface chemical composition have been documented and are presented in the paper.
Studies Regarding the Hardness and Microhardness of Al-Si Alloys Solidified in Ultrasound Field
Authors: Porcar Dan , Domşa Şerban , Jumate Nicolae , Porcar Iozefina
Published: March 2009

The paper presents an experimental study regarding two Al-Si alloys concerning the influence of ultrasonic treatment on the hardness and microhardness. AlSi12 ultrasound treated function as time hardness important decreases are observed. AlSi7 ultrasound treated function as time hardness easily increases is observed. The contradiction between two measurements was studied by microhardness of AlSi7 grain and eutectic mass materials. Important microhardness decreasing on eutectic mass materials is observed.
A Re-Examination of the Toughness and Fatigue Performance of PM Steels
Authors: Moon J.R.
Published: March 2009

It is now fairly well established that to achieve low values of the Paris exponent for the
growth of fatigue cracks in PM steels, high values of fracture toughness are required. Fracture
toughness is related to other measures of toughness, such as impact tests and the mechanical work
that the material can absorb before fracturing. All of these are functions of the basic ductility of the
material. A coherent picture of all these inter-relationships is presented.
Compositional and Processing Determination over Cermets’ Properties Al2O3-Ni with Metallic Admixtures
Authors: Cârlan P. , Chicinaş Ionel , Ducu C. , Stoica F.
Published: March 2009

It was studied the possibility to obtain cermets with nickel on alumina basis, using conventional methods such as cold pressing and sintering. γ transitional alumina was employed as oxide elemental, due to its OH- groups which have a positive effect to the press, by decreasing the friction forces. There were investigated the Al2O3-Ni cermets in the range where the concentration of the ceramic material is preponderant. Oxide and metallic admixtures were mixed in the powdered blend in order to study their influence on the properties of the cermets. These were characterized by measuring sintering density, hardness, bending strength and fracture toughness. The values of the characteristics are comparable to those reported in literature for non-conventional energetic methods: the sintered density up to 98%TD; the Rockwell hardness up to 40HRC; the bending strength up to 352MPa and the fracture toughness up to 4MPam0.5, function of their composition. The fracture has a mixed character, it is fragile-ductile.
Practical Guidebook for Elementary Engineering Management Education in Finishing Technology
Authors: Ioi Toshihiro , Ogawa Y. , Yamamoto Takeshi
Published: March 2009

The practice and evaluation of elementary management of technology (hereafter, MOT)
education has previously been investigated. It is recognized that elementary MOT education using
trading games (hereafter, TG) has great educational effects on the awareness of the importance of
MOT skills. On the other hand, a large amount of preparation time and labor is required when
elementary MOT education using TG is first introduced into elementary schools. Development of a
practical guidebook for elementary engineering management (hereafter, EM) education would
likely be a useful educational tool for elementary EM education, and may then be applied in many
elementary schools. In this study, a guidebook for elementary EM education is proposed, and its
educational effects are verified. The practical application of elementary EM education to the
finishing technology will be completed in the future works.
Study on the Cutting Parameter Optimization of Medical Titanium Alloy Based on Tools Durability
Authors: Du Q.L. , Chen X.H. , Zhang Ke Hua
Published: March 2009

In this paper, based on analyzing the properties of medical Ti-6Al-4V Titanium alloy, the
author takes the purpose of studying the machinability of the medical Ti-6Al-4V Titanium alloy and
aims at improving the tool durability. The study starts from the tool material, geometrical parameters
of the tools, usage for the cutting and other aspects in order to achieve the suitability of selecting
cutting tool as well as the optimization of choosing cutting usage which lays the foundation for
further investigation of the machinability of the medical Ti-6Al-4V Titanium alloy and carry out the
online optimization of cutting parameters.
Processing Flow of Optical Fabrication for Correcting Lenses
Authors: Zhang Yun , Zhi Jing Feng
Published: March 2009

This paper presents the processing flow and results of optical fabrication for an optical correcting lens with a free-form surface, namely a free-form lens. Because a correcting lens has no rotation axes of symmetry and its surface cannot be expressed by a continuity equation, its processing technology is different with that of general aspheric lenses. The correcting lens was firstly formed from a glass workblank with flat face using diamond abrasion wheel with spherical shape, and then loose abrasive lapped and polished with oblique axis spherical tools to decrease the surface roughness and increase the surface accuracy based on the measuring result after forming. At the lapping and polishing stages, two processing methods are employed. One is to control the processing pressure, and the other is based on dwell time. Since high precision fabrication is closely related with high precision measuring, this paper also presents a high precision non-contact optical measuring method based on image transforming for correcting lenses. The effectiveness of the processing flow and technology is confirmed by an experiment in which a workblank is processed into a satisfying correcting lens.
Study on Contact Pressure between Grain and Workpiece during Floating Polishing
Authors: Xu Xiao Cun , Yuan Zhe Jun , Lin Bing
Published: March 2009

Since almost large die surfaces are free-form surfaces, currently, these are almost manually
implemented. In order to overcome this barrier, floating polishing is a feasible polishing technology.
The contact pressure between grain and workpiece is a key problem of floating polishing technology.
This paper focuses on contact pressure between grain and workpiece. At first, study the friction bound
condition between grain and workpiece by ANSYS analysis software, then, compare with the analysis
results of slip-line field theory and the test results of single grain. The results show the feasibility of
the hypothesis of full friction condition. Finally, study the contact pressure between polishing disk
and workpiece using the analysis results of single grain. The research achievements will be used for
developing the floating polishing.
Investigation into LST and its Novel Application in Mould
Authors: Wang Yun , Xu Z.Y. , Fu Y.H. , Cai Lan
Published: March 2009

Laser surface texturing (LST) technology that is firstly used in rollers, is a specialized surface engineering process capable of enhancing the surface material properties, wear resistance, fretting fatigue life and reducing friction. This practical technology of the LST process is based on a pulsating laser beam that, by material ablation, generates the optimum topographical surface. In order to exploit the full potential of the process, a great amount of research has explored from the material removal mechanics to the development of the LST process. This paper reports on the LST research involving the LST technology surveying process optimization, LST equipment and its industrial applications. The paper also highlights the forming theory describing the skin-pass process of transferring the textured roller’s surface structure onto the steel sheet, and the laser-matter interaction that occurs when and intense laser beam is tightly focused in the workpiece surface. It presents the influence of various factors affecting the textured workpiece performance together with the investigations into tribology of textured components. The paper also discusses these developments and some fundamental on future LST research.
Study on Macro/Micro Complex Feed Mechanism in Dry-ECD Assisted Truing and Dressing of Diamond Wheel
Authors: Wang Yan , Wang Shi Ming , Zhou H. , Hu De Jin
Published: March 2009

A novel truing and dressing method, namely dry electrical discharge (dry-ECD) assisted
truing and dressing, is proposed to overcome the shortcomings associated with conventional
mechanical dressing methods, ELID and ECD methods. The macro/micro complex feed mechanism
in dry –ECD assisted truing and dressing equipment is designed to maintain continuous discharge
between the tool electrode and diamond wheel in dry-ECD automatically. A series of basic
performance experiments of the micro feed mechanism show that the position accuracy of the
micro-feed mechanism is below 0.35μm using the micro-positioning control system. Whereas，the
position accuracy of the mobile negative electrode is 1μm without macro/micro complex feed
mechanism.
The High-Efficient Low-Cost Wheel-Grinding Technology for CVD Diamond Films
Authors: Jin Zhu Ji , Ma Xing Wei , Yuan Ze Wei
Published: March 2009

CVD diamond films have been used in many high-tech fields with the industrial and scientific developments, while the lagging of the polishing technology for the CVD diamond films has limited their widely applications. This paper presents a high-efficient low-cost wheel-grinding technology for CVD diamond polishing, and the two key techniques of this technology are introduced in detail based on thermo-chemical polishing technology. Furthermore, wheel grinding technology exhibits a promising perspective for the widely application in the diamond films.
Optimization of Bulkhead Processing Sequence for Multi-Frame Monolithic Components by FEM
Authors: Tang Zhi Tao , Liu Zhan Qiang , Ai Xing
Published: March 2009

When machining aerospace monolithic components, most of materials could be removed,
resulting in severe deformation of the parts due to the release and redistribution of the blank’s original
residual stress, together with the action of cutting loads and clamping force. A finite element model
(FEM) is built for predicting the deformation caused by those factors mentioned above. In this model,
some key techniques such as material properties, initial residual stress model, and application of
dynamic cutting loads and transformation of boundary condition are discussed in details. The
proposed model predicts the machining deformation for multi-frame monolithic components.
Particular attention is paid to the influence of the bulkhead processing sequence on part deformation.
At last the paper puts forwards optimal bulkhead processing sequence based on minimizing the
machining deformation.
Mechanism Influence on Fatigue Characters of Aerial Engine Blade by Laser Shock Processing
Authors: Ren Xu Dong , Zhang Yong Kang , Li Y.H. , Cheng W. , Zhuang M.
Published: March 2009

In Laser Shock Processing when a material is irradiated with short laser pulses (ns)of very high densities(>GW/cm2), a high intensity shock wave is generated. This treatment can reduce the rate of fatigue cracking and stress corrosion cracking in structural metals or alloys needed for aerospace, nuclear power plants, and military applications. And laser shock processing has been shown to be a viable method of strengthen metallic components. Transformation on the characters of aerial engine blade by laser shock processing and influence on the fatigue life with these transformations were studied. And the relatively fatigue life experiment of aerial engine blade was done to validate the influence on the fatigue life of aerial engine by laser shock processing. It was found that laser shock processing could bring residual compressive stress and high-density dislocation on the surface of the blade. All these transformation greatly increase the fatigue life of aerial engine blade.
Application of Taguchi Method for Optimization of Finishing Conditions in SUS440 Stainless Steel Substrate
Authors: Zhu Cong Rong , Yuan Ju Long , Lv Bing Hai , Zhou Zhao Zhong
Published: March 2009

This paper focuses on the application of Taguchi method for optimization of SUS440
stainless steel polishing process parameters to obtain the best finish. An optimization experiment for
polishing stainless steel with SiO2 was designed by Taguchi method. Surface roughness Ra is
considered as criteria for optimization. Influence of parameters involving load, speed, and slurry
concentration for a given workmaterial with given abrasive (material and size) are discussed, and the
optimum polishing conditions are figured out. Compared with single parameter experimental results,
it illustrates that the experiment design based on Taguchi method can successfully applied to
determine the optimum processing conditions for SUS440 stainless steel polishing process.
Influence of Reaction Temperature for the Manufacturing of Al-3Ti and Al-3B Master Alloys and their Grain Refining Efficiency on a Al-7Si Alloy
Authors: Kori S.A. , Auradi V.
Published: March 2009

In the present work binary Al-3Ti and Al-3B master alloys were prepared at different reaction temperatures in an induction furnace by the reaction of halide salts like potassium fluoborate and potassium titanium fluoride with liquid molten Al. The indigenously developed master alloys were used for grain refinement studies of Al-7Si alloy and evaluated for their grain refining ability by CACCA studies. The present results suggest that, the reaction temperature influences the size, size distribution and morphology of the intermetallic (Al3Ti in Al-3Ti, and AlB2/AlB12 in Al-3B) particles present in Al-3Ti and Al-3B master alloys. Grain refinement studies of Al-7Si alloy reveal that, Al-3Ti and Al-3B master alloys prepared at 8000C-60 min. have shown better grain refining efficiency on Al- 7Si alloy when compared to the master alloys prepared at 9000C-60 min and 10000C-60 min respectively. In addition, B-rich Al-3B master alloy shows efficient grain refinement than Ti rich Al- 3Ti master alloy.
Characterisation of Ti(Al,O)-Al2O3 Composite Powders and Thermally Sprayed Coatings
Authors: Salman Asma , Gabbitas Brian , Zhang De Liang , Cao Peng , Raynova Stella
Published: March 2009

A feedstock of Ti(Al,O)-Al2O3 composite powders was produced by high energy milling
of a mixture of Al and TiO2 powders followed by a thermal reaction process. The feedstock was
then thermally sprayed using a high velocity oxygen-fuel (HVOF) technique on H13 steel substrates
to produce Ti(Al,O)-Al2O3 composite coatings. The performance of the coatings was assessed in
terms of thermal fatigue behaviour and reaction with molten aluminium (soldering). The composite
powders and coatings were characterised using scanning electron microscopy (SEM) and X-ray
diffractometry (XRD). This paper reports the experimental observations and discusses
characteristics and potential applications of the composite coatings.
A Novel Process for Lowering the Cost of Titanium
Authors: Adam Gorgees , Zhang De Liang , Liang Jing , Macrae I.
Published: March 2009

Titanium and titanium alloys are the materials of choice for many industrial applications because of their attractive combination of low density, good mechanical properties, and high corrosion resistance, and titanium is the fourth most abundant metal in the earth crust (0.86 % by weight) behind aluminum, iron, and magnesium. However, titanium and titanium alloys are not widely. The reason for this is the high cost of titanium and titanium alloys! The cost gap for titanium and titanium alloys widens when they are used for fabricating components and structures. Consequently, much effort has been expended to reduce the cost of titanium and titanium alloys. In conjunction with the University of Waikato, Titanox Development Limited-New Zealand has been successful in creating a modified novel process to produce TiAl based alloy powders with different particle sizes and compositions at low cost. The process offers several benefits to the titanium industry the most significant one of which is that it displays the potential to significantly reduce the commercial production costs of Ti-Al based alloys. This paper describes the Titanox Development Limited technology in brief, and shows how it can economically produce titanium alloy powders for different industrial applications and making titanium alloys affordable. The process has been disclosed in a PCT (Patent Corporation Treaty) application which was approved in 2004 [1], and the related patent applications either have been approved or are being filed in different countries.
Effect of Carbon Addition on the Microstructure and Properties of M3:2 High Speed Steels Processed by Powder Metallurgy
Authors: Zhou R. , Wang D. , Shen Jun , Sun J.
Published: March 2009

M3:2 high speed steels with and without carbon addition were prepared by using powder
metallurgy at sintering temperature between 1210 and 1280 °C. Densification, microstructure and
mechanical properties of M3:2 high speed steels were investigated. Experimental results show that
with 0.4wt% carbon addition, full density high speed steels were obtained at temperatures in the
range 1240-1260 °C which is 40 °C lower than that of the undoped counterparts, leading to a sintering
window expanded by 10 to 20 °C. By the addition of 0.4wt% carbon, the sintered steels show
attractive combinations of bend strength and hardness over those of M3:2 steels without carbon
addition. The results reveal that the addition of carbon will not only lower the sintering temperature
and oxygen content, but also improve the mechanical properties of the sintered steels.
Processing of Mullite Whiskers from Kaolin
Authors: Kim B.M. , Yang Tae Young , Yoon Seog Young , Stevens Ron , Park Hong Chae
Published: March 2009

Mullite whiskers have been manufactured by firing compacts of kaolin, Al2(SO4)3 and (NH4)2SO4 powders, with a small addition of Na2SO4, in air at 1400o C for 15 h. From the batch composition of Al2O3/SiO2 = 0.7, molar ratio, alumina-deficient (Al2O3/SiO2 = 1.02, molar ratio), orthorhombic mullite whiskers with an aspect ratio of >30 (0.2-0.4 μm in diameter) were obtained. With increasing Al2O3/SiO2 molar ratio, the size and aspect ratio of the mullite whiskers decreased.
Joining of Ceramic Components in the Green State via LPIM
Authors: Waesche Rolf , Paulick Carl , Steinborn Gabriele , Richter V. , Werner M.
Published: March 2009

It has been successfully demonstrated that ceramic materials can be joined in the green
state without a second phase by using low pressure injection molded parts. The investigation of the
joining interface revealed that a high quality interface can be achieved by carefully adjusting the
different manufacturing steps. The use of monomodal particle size distribution in the used powder
CT3000SG is inferior to a broader particle size distribution obtained by replacing 33% of the finer
alumina powder by coarser CT1200SG. In this way the dewaxing process is significantly improved
when the wall thickness of the part exceeds 3 mm. The investigation of the mechanical properties of
the joined and sintered parts revealed, that the bending strength of the joined specimens achieved
about 80 % of the unjoined, monolithic specimens.
Fabrication and Microstructure Evaluation of Oxide and Carbide Ceramic Coatings onto Heterogeneous Substrates by Solid-Vapor Reaction
Authors: Kang Jin Ho , Bao Q.H. , Jung Yeon Gil
Published: March 2009

Silicon carbide (SiC) and alumina (Al2O3) have been synthesized on graphite and silica
(SiO2) substrates, respectively, using a solid-vapor reaction (SVR). SiC and Al2O3 layers are
synthesized on each substrate by reacting between SiO vapor and substrate (SiO (vapor) + 2 C (from
graphite)), and between AlO vapor and substrate (2AlO (vapor) + 1/2O2 (from SiO2)). Both reaction
processes were performed at 1400 °C for 9 hour at a heating rate of 5 °C/min under an Ar/H2
(160:40) flow of 200 sccm (ml/min). The pack composition for each case was adjusted with 1:1
mole ratio, which was used as precursors of the AlO and SiO vapors. The synthesized SiC layer
consists of α-SiC and β-SiC, and its thickness is affected by the porosity of graphite. The Al2O3 top
layer synthesized on SiO2 substrate is coarse and relatively porous, resulting in some defects.
Rheological Characterization of Jute/HDPE Composites
Authors: Mohanty S. , Nayak S.K.
Published: March 2009

The present paper summarizes an experimental study on the molten viscoelastic behavior of HDPE / jute composites under steady and dynamic mode. Variations of the melt viscosity and die swell of the composites with an increase in shear rate, fibre loading and coupling agent concentration have been investigated using capillary rheometer. It was observed that the melt viscosity of the composites increased with addition of fibres and MAPE. Further, the dynamic viscoelastic behavior of the composites was measured employing parallel plate rheometer. Time temperature superposition was applied to generate various viscoelastic master curves. The fibrematrix morphology of the extrudates were also examined using scanning electron microscopy.
Natural Fibre-Reinforced Thermoplastics Processed by Rotational Moulding
Authors: Jayaraman Krishnan , Lin Richard , Bose D. , Maarouf M.
Published: March 2009

Rotational moulding or rotomoulding is a manufacturing process best suited for
producing one-piece, hollow plastic products. The raw materials can be in powder or liquid form
with linear polyethylene of varying densities being dominant worldwide. Due to the modest
material properties of polyethylene, reinforcement in various forms have been incorporated within
the rotomoulded components to improve the performance of these products. With the abundance
and eco-friendliness of natural fibre resources, this study has focused on the use of sisal and
woodfibres along with linear medium density polyethylene (LMDPE) powder to produce
rotomoulded composite components. Tensile and impact properties of the rotomoulded natural
fibre-reinforced composites have been determined as a function of fibre content.
Accelerated Weathering of Modified Wood Flour Plastic Composites
Authors: Fabiyi J.S. , McDonald A.G.
Published: March 2009

The effect of accelerated weathering on the chemical and color of wood plastic composites (WPC) made from modified pine wood fiber (control, extractives free and holocellulose) was investigated. WPC were produced from the various wood fibers (60%, weight) and high density polyethylene (40%, weight) as matrix were subjected to accelerated weathering in xenon-arc weatherometer for up to 1200 hours. This study aimed at getting a better understanding of the chemical changes that occur to weathered WPC relative to its material compositions (wood and plastic). Chemical analyses and color measurement of the weathered surface using Fourier transform infrared (FTIR) spectroscopy, pyrolysis gas chromatograph mass spectrometry and colorimetery showed that degradation of WPC had occurred, causing color changes. It was observed that WPC made from holocellulose wood fiber had the lowest color change compared to extractives free wood and control wood fiber based WPC.
Improvement of the Red Mud Polymer-Matrix Composites by Organophillization of Red Mud
Authors: Bhat A.H. , Banthia A.K.
Published: March 2009

Red mud was organophilized by aniline formaldehyde and to know the effect of various filler
loading on the properties of PVA-Organophilized red mud composite prepared by a conventional
solvent casting technique and comparison of the same with that of the virgin polymer, various
characterizations was done. The as-synthesized composite films were typically characterized by
FTIR spectroscopy and X-Ray Diffraction.The exfoliation of galleries of organo- red mud was more
evident in the composite film containing 2% of filler loading.The morphological image of the
composite materials was studied by scanning electron microscopy (SEM) and optical microscope
(OM). The thermal properties measured by thermogravimetric analysis (TGA) showed that organored
mud enhanced the thermal stability of a series of composite materials freestanding films.The
differential scanning calorimetry (DSC) showed increase in glass transition temperature and
crystallization of the composite films.
Hemp Fibre Reinforced Poly(Lactic Acid) Composites
Authors: Sawpan M.A. , Pickering K.L. , Fernyhough Alan
Published: March 2009

The potential of hemp fibre as a reinforcing material for Poly(lactic acid) (PLA) was investigated. Good interaction between hemp fibre and PLA resulted in increases of 100% for Young’s modulus and 30% for tensile strength of composites containing 30 wt% fibre. Different predictive ‘rule of mixtures’ models (e.g. Parallel, Series and Hirsch) were assessed regarding the dependence of tensile properties on fibre loading. Limited agreement with models was observed. Differential scanning calorimetry (DSC) and x-ray diffraction (XRD) studies showed that hemp fibre increased the degree of crystallinity in PLA composites.
Actuation Behavior of CP Actuator Based on Polypyrrole and PVDF
Authors: Ha J.M. , Lim Hyun Ok , Jo Nam Ju
Published: March 2009

Conducting polymer (CP) actuators undergo volumetric changes due to the movement of
dopant ions into the film during the electrical oxidation process. In this work, PPy/SPE/PPy
electroactive tri-layer actuator was prepared by the electrochemical polymerization of pyrrole and the
actuation characteristics were studied. An all-solid actuator, consisting of two polypyrrole (PPy) films
and a solid polymer electrolyte (SPE) based on poly(vinylidene fluoride) (PVDF), clearly showed a
reversible displacement in an atmosphere when a voltage was applied.
A Novel Nano-Water-Purifying Material
Authors: Han W. , Lu Ming Xia , Wang H. , Liu G.
Published: March 2009

Water contaminated by heavy metals remains a serious environmental and public health
problem. The toxic effects of heavy metals on the biosphere have been demonstrated by a number of
studies. Since the main sources of heavy metals for humans are water and food, the monitoring of the
heavy metals content in natural water is of paramount importance. Diverse technologies have been
used to reduce the contents of heavy metals in water. Recently, adsorption methods have been widely
used because of their low cost. The novel nano-water-purifying material used in our work is
composed of AlO(OH) nanoparticles loaded onto glass fibre and supported by active carbon felt. The
Al nano-powder starting material, was prepared using an electric explosive technique. The products
were characterized by X-ray diffraction, scanning electron microscope, transmission electron
microscope, and BET techniques. It was found that the particles consisted of AlO(OH) nanofibres of
pure boehmite structure. They exhibited a surface area of 431.7 m2 / g. The composite material was
found to be effective in removing cadmium from dilute aqueous solutions and could find broad
application in heavy metal removal.
Warm Hydroformability and Mechanical Properties of Pre- and Post- Heat Treated Al6061 Tubes
Authors: Yi Hyae Kyung , Lee Jung Hwan , Lee Young Seon , Moon Young Hoon
Published: March 2009

Warm hydroformability and mechanical properties of pre- and post- heat treated Al6061
tubes were investigated in this study. For the investigation, as-extruded, fully annealed and T6-
treated Al 6061 seamless tubes were prepared. To evaluate the hydroformability, uni-axial tensile
test and free bulge test were performed at room temperature and 200ÓC. Also mechanical properties
of hydroformed part at various pre- and post-heat treatments were evaluated by tensile test. The
tensile test specimens were obtained from hexagonal shaped tube hydroformed at 200ÓC forming
temperature. As a result, hydroformability of fully annealed tube is 25% higher than that of
extruded tube. The tensile strength and elongation were more than 330MPa and 12%, respectively,
when hydroformed part was T6 treated after warm hydroforming. However, hydroformed part using
T6 pre treated tube represents low elongation, 8%. Therefore, the T6 treatment after hydroforming
for as-extruded tube is proved to be the most cost-effective among various processing conditions.
Advanced Wood- and Bio-Composites: Enhanced Performance and Sustainability
Authors: Winandy Jerrold E.
Published: March 2009

Use of wood-based-composites technology to create value-added commodities and traditional
construction materials is generally accepted worldwide. Engineered wood- and lignocellulosiccomposite
technologies allow users to add considerable value to a diverse number of wood- and
lignocellulosic feedstocks including small-diameter timber, fast plantation-grown timber,
agricultural fibre and lignocellulosic residues, exotic-invasive species, recycled lumber, and timber
removals of hazardous forest-fuels. Another potential advantage of this type of economic- and
materials-development scenario is that developing industrial composite processing technologies
will provide producers an ability to use, and to adapt with, an ever-changing quality level of wood
and/or other natural lignocellulosic feedstocks. However, the current level of performance of our
state-of-the-art engineered composite products sometimes limit broader application into
commercial, non-residential and industrial construction markets because of both real and perceived
issues related to fire, structural-performance, and service-life. The worldwide research community
has recognized this and is currently addressing each of these issues. From a performance
standpoint, this developing knowledge has already and will continue to provide the fundamental
understanding required to manufacture advanced engineered composites. From a manufacturing
and a resource sustainability standpoint, with this evolving fundamental understanding of the
relationships between materials, processes, and composite performance properties we now can in
some cases, or may soon be able to, recognize the attributes and quality of an array of bio-based
materials then adjust the composite manufacturing process to produce high-performance composite
products. As this fundamental understanding is developed, we will increasingly be able to produce
advanced, high-performance wood- and bio-composites. Then we must use those technologies as
tools to help forest and land managers fund efforts to restore damaged eco-systems and which in
turn may further promote sustainable forest management practices.