bluuebunny/crossref_metadata_2025 huggingface dataset:
Solid State NMR Study of Calcium Fluoroaluminosilicate Glasses
Authors: Karpukhina Natalia , Law Robert V. , Hill Robert G.
Published: March 2009

Fluorine containing calcium aluminosilicate glasses are widely used for a number of
technological applications including dental cements, mould fluxes in steel making and in a variety
of glass-ceramic systems. Despite of their importance these systems remain quite poorly understood
with respect to their composition. To address this question a glass composition corresponding to the
equimolar binary system anorthite−fluorite (Ca2Al2Si2O8−CaF2) was chosen as a base point for two
series of compositions. One of the series is designed on the anorthite stoichiometry and considered
as classically charge balanced. Another series starts from the fluorine free composition of the
anorthite−lime (Ca2Al2Si2O8−CaO) stoichiometry and, therefore, is characterized by a disrupted
network with at least one non-bridging oxygen (NBO) attached to silicon. A multinuclear 19F, 27Al,
29Si solid state NMR study of the glasses was undertaken. It is shown that in both series fluorine is
predominantly coordinated by calcium, F−Ca(n), and in addition interacts with aluminium forming
Al−F−Ca(n) complexes, where n denotes the number of first neighbouring calcium cations. Small
amounts of high coordinated aluminium grows with increasing fluoride content in both glass series.
However, the high coordinated aluminium may not be solely due to the formation of the
Al−F−Ca(n) complexes. Glasses of the first series displayed systematic upfield shift of 29Si NMR
resonance while substituting fluoride for oxide, starting from the fluorine free composition. This
upfield shift is interpreted as the lack of cations in the network, due to formation of the F−Ca(n),
which drives silicon network to polymerize toward a higher Qn structure. Contrary to the first series,
the 29Si NMR resonance remains constant for fluorine containing compositions of the second series
but differs downfield from the initial anorthite glass. The latter is explained by the excess of cations
in the network due to addition of the fluorite resulting in formation of NBO on the silicon. Binding
of fluorine with silicon is considered negligible in these systems. Thus, fluorine and calcium both
define the degree of network polymerization and are considered as a cause for the changes in silicon
and aluminium networks.
Anomalously Low Light Scattering in the Na2O-Nb2O5-SiO2 Glass-Ceramics
Authors: Shepilov Michael , Dymshits Olga , Golubkov Valerii V. , Zhilin Alexander A.
Published: March 2009

An evolution of the structure of three glasses of Na2O-Nb2O5-SiO2 system in the course
of isothermal heat treatments at 660–700°C and the extinction coefficient of the material were
studied. Spinodal phase separation was found to be a primary process followed by precipitation of
nano-sized NaNbO3 crystalline phase. It was found that the spectral dependence of the extinction
coefficient in the wavelength range λ= 400–800 nm corresponds to light scattering by spinodal
structure at the phase separation stage and by independent Rayleigh scatterers (NaNbO3
nanocrystals) at the early stage of crystallization. The extinction coefficient increases at the first half
of the crystallization stage and then decreases. At the late stage of crystallization and for the final
glass-ceramics, the extinction coefficient α is 10–20 times smaller than that calculated for
independently scattering nanocrystals and is characterized by anomalous wavelength dependence
(α ∝ λ−6). The model for calculation of extinction coefficient is proposed, in which the interference
effects in light scattering by nanocrystals are taken into account. On this basis, the variation of
extinction coefficient in the course of crystallization and its wavelength dependence are explained.
Simulation of the Chemical Influences to the Polishing Process of Optical Glasses
Authors: Becker Elisabeth , Prange Andreas , Conradt Reinhard
Published: March 2009

In the last step of fabrication, optical and fine-optical glasses are polished to fulfill the
optical requirements for their surfaces. The major influences on the process are caused by the
mechanics of the polishing machine, by the chemistry (composition of the glass, as well as the
polishing suspension of water and polishing grains, CeO2) [1], [2] and by the material and structure
of the polishing pad.
From previous own results [3], [4] it is known that the stability of the colloidal system has a major
impact on the polishing results and that it is influenced by matter from the glass removal. Thus the
glasses have been classified in glass families, depending on their chemical composition and their
mutual compatibility in the process. As it is not always possible to measure this compatibility, the
impact of the various dissolved glass ions in the fluid phase of the polishing suspension is simulated
by the use of thermodynamic parameters. Therefore the specific solubility products in the aqueous
phase are modeled (using, e.g., the software HSC) comprising steady accumulation of ions from the
glass removal.
With this simulation, the examination of the chemical part of the chemo-mechanical polishing
process will be concluded.
Structural Features of Nano-Scaled Metamaterials Containing PbS Nanocrystals
Authors: Onushchenko A.A. , Golubkov Valerii V. , Zhilin Alexander A.
Published: March 2009

Formation processes and morphology of nanostructured glass ceramic materials containing finely
dispersed lead sulfide crystalline phase has been studied by X-ray technique. The spatial ordering of
PbS nanocrystals has been revealed which manifests itself by interference effects in X-ray
scattering. We have ascertained that important morphology feature of the system is nearly
monodisperse size distribution of nanocrystals.
The Corrosion of E-Glass Fibres in Complexing Organic Acids
Authors: Jones Robert L.
Published: March 2009

This paper examines the leaching patterns of pyruvic acid, and relates this to similar
patterns of oxalic, glyoxylic and malonic acids in a further attempt to clarify the mechanism of the
corrosion process. It appears that these acids selectively leach boron to a greater extent than other
cations, and as boron is part of the E-glass matrix rather than just an interstitial ion, this would
explain the means by which these relatively weak acids are able to corrode the glass fibres. It is
well known that oxalic acid forms strong complexes with boron, and it is likely that other
dicarboxylic acids or carboxylic acids with appropriately placed ligand groups (e.g. glyoxylic acid)
will do likewise. This work presents a study of the rate of strength loss and the rate of leaching of
cations from E-glass fibres with particular emphasis on boron.
Crystallization of Glasses in the MoO3-Bi2O3 System
Authors: Iordanova Reni , Milanova Margarita , Stoyanova Angelina , Iliev Cvetoslav
Published: March 2009

α-Bi2Mo3O12 and β-Bi2Mo2O9 crystal phases have been synthesized by crystallization of
a glass for a short time. Amorphous samples with the compositions corresponding to the alpha and
beta bismuth molybdates have been obtained at high cooling rates (104-105 K/s). XRD, DTA and
SEM studies were performed to examine the phase formation, thermal behavior of the glasses and
the microstructure of obtained crystalline products. By scanning electron microscopy it was shown
that the obtained bismuth molybdates consist of dense agglomerates, containing uniform distributed
crystals with submicron size.
Evolution of Absorption Spectra in the Process of Nucleation in Photo-Thermo-Refractive Glass
Authors: Lumeau Julien , Glebova Larissa , Glebov Leonid B.
Published: March 2009

Photo-thermo-refractive (PTR) glass belongs to a class of photosensitive multicomponent
silicate glasses which demonstrate photo-thermo-induced precipitation of a crystalline
phase. Photo-induced crystallization of sodium fluoride results in refractive index variations in
exposed areas of PTR glass which was successfully applied for phase hologram recording.
However, even if this glass is widely used for advanced optical applications such as the stabilization
of laser diodes or spectral beam combining, the detailed mechanism of its photosensitivity is not
well known. We present in this paper an analysis of the evolution of the absorption spectra of UVexposed
PTR glass at the early stages of the thermal treatment (nucleation). Absorption spectra were
measured on samples nucleated at constant temperature for different periods. Analysis of the
structure of these spectra shows that the optimum of the nucleation process is associated with the
appearance of a new absorption band in visible range that disappears when the crystal growth
process starts. Analogous study was performed during the nucleation process. High temperature
spectroscopic measurements were performed during the thermal treatment. It was found that
absorption spectra evolve with a change of temperature, i.e. the band structure of these spectra is
different whether or not the temperature is decreased below a temperature of ~400°C. We associate
this process with the change of phase of the silver bromide nuclei (liquid/solid) that appears during
the cooling or heating processes.
Thermal Stability vs. Crystallization of the Lithiumsilicate Glasses with Addition Zirconium Dioxide and Titanium Dioxide
Authors: Pavlík Viliam , Jóna Eugen , Sapietová Martina , Šnircová Soňa
Published: March 2009

The glasses with composition of Li2O . 2 SiO2 . n ZrO2 . n TiO2 (where n = 0; 0.015;
0.031; 0.050; 0.075; 0.1; 0.15; 0.2) were prepared and the relationship between structural and
selected parameters of thermal stability vs. crystallization has been studied by differential thermal
analysis. Structural analysis was provided by X–ray diffraction. The order of thermal stability vs.
crystallization representing of activation energy of studied glass systems which increase with higher
addition both oxides. The same order was obtained from the values of XRD. On the comparison the
glasses with zero addition titanium dioxide their activation energy was much higher.
What is the Ideal Glass Bath Depth of a Glass Furnace?
Authors: Muijsenberg H.P.H. , Muijsenberg Marketa , Chmelar J.
Published: March 2009

Mathematical modelling is reaching a high acceptance level within the glass industry.
Today most new furnaces are being modelled before the final design is decided. It is clear that the
modelling helps to optimise the furnace in respect to glass quality, energy efficiency and furnace
life-time. The extra effort of the modelling is leading for sure to a quick pay-back of this extra
investment and an increased profit over the furnace life-time. Even the furnace life-time can be
extended with better insight on temperature distribution and glass speeds that corrode the refractory.
Many glass produces are always asking us: “what is the optimal glass depth”? There is not just one
answer to this, but the paper demonstrates how mathematical modelling can help to find the optimal
furnace depth for a certain furnace design.
Virtual Modeling of Dynamic Loading of Glass Mould
Authors: Matoušek Ivo
Published: March 2009

In the contribution problem of dynamic loading of glass moulds is analysed. Possibilities
of FEM for evaluation of tensile states initiated with temperature variations are shown on a
particular case. Critical areas where cracks nucleation as a result of thermal fatigue can be expected
are evaluated. Results are used for relative comparison of service life of mould with classical design
and mould with optimised design (with control cooling).
Behavior of Zinc Selenite, Calcium Selenite and Metallic Selenium as Decolorizing Agents in Flint Glass Production
Authors: Müller-Simon Hayo , Griebenow Peter
Published: March 2009

Zinc selenite, calcium selenite and metallic selenium have been consecutively introduced
as decolorizing agents in a flint glass production. The selenium concentration in the glass has been
measured by wet-chemical analysis, optically by the evaluation of the cielab a-value and
electrochemically by means of a voltammetric sensor. All measuring techniques showed the highest
selenium retention for calcium selenite followed by zinc selenite and the least retention using
metallic selenium. The best reproducibility is achieved using zinc selenite while both calcium
selenite and metallic selenium provide only poor reproducibility.
Numerical and Experimental Investigations on the Residual Stresses at the Centre of Flat Glass Disks After Thermal Tempering
Authors: Soulié Frédéric , Siedow Norbert , Anton John , Lochegnies Dominique
Published: March 2009

Flat glass disks are thermally tempered by air-cooling with two air jets at the centre of
their surfaces. Numerical modelling and photoelasticity measurements are proposed to analyze the
distribution of the residual stresses through the glass thickness at the centre of the tempered disks.
For the modelling, glass properties dependent of the temperature are used for the conductive heat
transfer. Radiation is modelled by an improved approximation method. By taking both structural
and stress relaxations into account, the transient and residual stresses are computed along the disk
thickness. For experimentation, a complete procedure is proposed to access to the stress state in the
centre of the disks using a scattered light polariscope. The average distribution of the residual
stresses is deduced from stress profile measurements taking four radial orientations at the disk
centre into consideration. Comparison between numerical and experimental values is finally
discussed for the residual surface and half-thickness stresses at the disk centre.
Analysis of Industrial Glass by Portable µ-EDXRF
Authors: Agostino Angelo , Falcone R. , Vallotto M. , Verità M.
Published: March 2009

Portable energy-dispersive micro X-ray fluorescence spectrometry (-EDXRF) is a useful
device for non-destructive chemical analysis of different materials. Despite its evident potential in
the fields of glass analysis, only few archaeometric studies have been performed yet. In this work
preliminary results on the analysis of different types of industrial glass by -XRF are presented in
view to apply this method in industrial applications (monitoring of glass cullet, production quality
control, classification of end products, etc.). The experimental results show a reliable qualitative
recognition of detectable elements in the glass. A good correlation line intensity/concentration was
verified for several important elements. Furthermore very low limits of detection were estimated for
critical elements such as Fe, Cr and Pb.
Defects of Golden and Luster Decorations on Glass
Authors: Hradecká Helena , Rohanová Dana
Published: March 2009

Decoration of glass by a thin layer of golden or luster solutions demands a high quality of the glass
surface, decorating solutions, as well as technological procedure. In the presented work the authors
monitored causes of defect formation for two types of luster decorations and two types of
commercial glass gilding preparations with various Ag contents. The results have shown that in
case of an unsuitable technological process the layers on the glass demonstrate insufficient
adhesion, colors different from the required shade or matt spots. The resistance of golden
decorations against damage was further tested by washing of decorated samples in a dishwasher. In
case of alkaline washing the decorations were more resistant on sodium-potassium glass and on a
previously dealkalised glass surface. A high durability against washing was found for the golden
decoration with high Ag content. The quality of layers was investigated with a spectrophotometer,
optical microscope and SEM and compositions of the original and decorated glasses were
determined with RTG-F and SEM/EDS analyses.
Recent Problems in Glass Melting from the View Point of Refractory and its Solutions
Authors: Kido Nobuyuki
Published: March 2009

In these years, glass industry has several problems to solve which are derived from
environmental protection, energy saving, resource saving, demands for high quality glass and so on.
Refractory for the glass melting also has some problems corresponding to the glass industry, such as
more corrosive service circumstance, less glass contamination from the refractory, recycling and so
on.
NOx reduction, one of the environmental protection, brings the oxy-fuel combustion and/or the
reducing atmosphere operation of glass melting into the glass industry.
Under the reducing atmosphere, some kind of refractories can not endure for a long period of time
and under the oxy-fuel combustion, refractories ought to endure around 3 to 4 times more severely
corrosive circumstance.
Thus, the problems of refractory that are corresponding to the glass industry are explained and
discussed in this presentation.
The solutions for the above are also discussed and presented, if possible in the presentation.
The Microstructure of Fused Cast AZS Materials before, during and after the Use for Glass Melting
Authors: Fleischmann Bernhard
Published: March 2009

A part of a soldier block, placed in a float glass furnace near the hot spot area, was
investigated to learn about the changes in the microstructure during the production of the block,
during the use for glass melting and after the shut down of the furnace and the cooling of the block.
Beside the three phases after the production (baddeleyite, corundum, vitreous phase) during use as a
soldier block mullite and secondary corundum as well as secondary zirconia may occure. Cooling
down the used block after the furnace campaign the beginning of the crystallisation of feldspars
may be seen.
Characterization of Aluminophosphate Glasses Containing Pr3+, Er3+, Gd3+ and Yb3+ Ions
Authors: Elisa M. , Vasiliu Ileana Cristina , Grigorescu Cristiana Eugenia Ana , Grigoras B. , Niciu H. , Niciu Daniela , Meghea Aurelia , Iftimie Nicoleta , Giurginca Maria , Roxana Patrascu , Trodahl Joe , Dalley M.
Published: March 2009

A wet non-conventional method for preparing aluminophosphate glasses is presented.
Aluminophosphate glasses belonging to the oxide system Li2O-BaO-Al2O3-La2O3-P2O5, doped with
rare-earth ions (Pr3+, Er3+, Gd3+, and Yb3+) were obtained. The influence of the doping ions on the
optical properties of the phosphate glasses has been investigated in relation with micro-structural
and local electronic phenomena The optical behavior of Li2O-BaO-Al2O3-La2O3-P2O5 glasses
doped with 3% mol. rare-earth ions has been studied by ultra-violet-visible-near-infra-red (UV-VISNIR)
spectroscopy. The transmission spectra revealed electronic transitions between 4f and 6s inner
orbital of the rare-earth ions. Structural information via optical phonons was provided by infra-red
(IR) absorption spectra in the range 400-4000 cm-1. IR optical phonons are characteristic for the
vitreous phosphate network, showing out the glass network-forming role of P2O5. The absorption
spectra present the main PO2 and P-O-P symmetrical stretch modes besides P-O-P bend mode, P-OH,
P=O, PO3
2-, asymmetrical and symmetrical vibration modes. Fluorescence spectra of the rareearth-
doped aluminophosphate glasses, in the visible range, were obtained by laser excitation at
514.5 nm. The fluorescence signals revealed specific electronic transitions, which provide visible
and near-infra-red emission. Glasses containing rare-earth ions exhibit luminescence at the
following wavelengths: Pr3+ ions at 820 nm and 880 nm, Er3+ ions at 520 nm, 550 nm and 560 nm,
Gd3+ ions at 530 nm, 540 nm, 550 nm 820 and 880 nm, Yb3+ions at 530 nm, 540 nm, 550 nm and
980 nm.
Structural Model of K2O-GeO2-P2O5 Glasses Based on Diffraction Results
Authors: Hoppe U. , Walter G. , Brow R.K. , Wyckoff N.P.
Published: March 2009

An increase of the Ge–O coordination numbers (NGeO) from 4 to 5 with decreasing GeO2
content is obtained by diffraction on K2O-GeO2-P2O5 glasses of GeO2 fractions ≥ 50 mole%. First
sharp diffraction peaks (FSDP) appear at small scattering vectors Q of 7.5 nm-1. A structural model
is already reported which explains this behaviour for that sample (25K2O-50GeO2-25P2O5) with the
FSDP reaching maximum intensity and NGeO = ~5. Here, this model gets support by considering the
detailed fractions of the structural groups which exist at the corresponding glass stoichiometry.
Structures similar to this model are not known of the crystalline germanophosphate compounds.
Glass Formation and Structure of the Glasses in the MoO3-Nd2O3-Bi2O3 System
Authors: Iordanova Reni , Aleksandrov Lyubomir , Stoyanova Angelina , Dimitriev Yanko B.
Published: March 2009

Low melting glasses in the MoO3-Nd2O3-Bi2O3 system were obtained at slow (102 K/s)
and high cooling rates (104-105 K/s). The amorphous state of the samples was proved by X-ray
diffraction. Comparative analysis of the infrared spectra of the obtained glasses and other available
molybdate spectral data was carried out. The structure of glasses with a high MoO3 content was
found to consist of corner shared MoO6 units. The increasing of Nd2O3 and Bi2O3 lead to partial
transformation of MoO6 to MoO4 units, due to breaking of Mo-O-Mo linkage.
Diagnosing Boiler Tube Failures Related to Overheating
Authors: Lobley Graham R. , Al-Otaibi Waleed L.
Published: March 2009

Unexpected tube failure is the major factor causing unreliability in utility boilers. The
first step in analyzing tube failures is to identify the active damage mechanisms. Three tube
damage mechanisms related to overheating are presented and possible root causes are discussed to
resolve these tube failures. Damage mechanisms can be recognized by metallurgical evaluation,
comprising a combination of both visual and microexamination, complemented by chemical
analyses of tube or fireside deposits, as appropriate. Characterizing the degree of microstructural
degradation can also help to confirm and separate various potential high temperature tube damage
modes, such as long or short term overheating, as well fuel ash attack. Carbon steel is the standard
tube material for high pressure boilers (typically up to 625 psig steam) and has a normal design
temperature limit of about 440 °C. However, microstructural changes occurring as a result of higher
temperature exposures in service can include carbide spheroidization, graphitization and other
transformations. Metallography is powerful tool for evaluating overheated failures and also for fire
damage assessment. Evaluating overheated steel microstructures utilizes the principles of steel heat
treatment and application of the iron-iron carbide equilibrium diagram.
Strength and Plastic Deformation Behavior of Nano-Scale Au/Cu and Cr/Cu Multilayers
Authors: Li Y.P. , Zhang G.P. , Wang Z.G.
Published: March 2009

Nano-scale Au/Cu multilayers were investigated by nano/microindentation. It was found
that the hardness of the multilayers increases with decreasing individual layer thickness (λ), and
shear band deformation can occur more easily in the multilayer with small λ. For comparison, the
same experiments were also performed on Cr/Cu multilayers with the same layer structure. The
results show that the Cr/Cu multilayer can be more effective in resisting shear band deformation
than the Au/Cu multilayer. Finally, the λ dependence of shear band deformation and the difference
between plastic deformation behaviors of the two multilayers were analyzed based on dislocation
plasticity.
Indentation Creep and Adhesion of Hybrid Sol-Gel Coatings
Authors: Latella Bruno A.
Published: March 2009

In this study the creep behaviour and adhesion characteristics of hybrid sol-gel silica-based coatings
on copper substrates was examined. Sol-gel technology was used to synthesize the organically
modified silanes using mixtures of tetraethoxysilane and glycidoxypropyltrimethoxysilane
precursors. The creep properties and adhesion behaviour of the coatings were assessed using
nanoindentation and microtensile testing, respectively. The link between film structure and creep
behaviour was explored. It is shown that the creep response of the coatings is influenced
dramatically by the introduction and quantity of the organic substituent.
Mechanical and Physical Properties of Recycled Cellulose Fibre-Reinforced Epoxy Eco-Composites
Authors: Sommers J. , Kho H.S. , Al-Ghamedi R. , Low It Meng , Davies Ian J. , Latella Bruno A.
Published: March 2009

Epoxy composites reinforced with recycled cellulose fibre (RCF) have been synthesized
and characterized. The reinforcement by RCF has resulted in a significant increase in the strain at
break, fracture toughness and impact toughness but moderate increase in flexural strength and
flexural modulus. The effect of seawater soaking on the flexural and impact properties has also been
investigated. The micromechanisms of toughening and crack-tip failure processes are identified and
discussed in the light of observed microstructures from in-situ and ex-situ fracture.
Corrosion Resistance of Electrodeposited RE-Ni-W-P-SiC-PTFE Composite Coatings
Authors: Zhu Xiao Yun , Guo Zhong Cheng , Yang Xian Wan
Published: March 2009

Corrosion rates and anode polarization curves of RE-Ni-W-P-SiC-PTFE
composite coatings in various concentrations of sulfuric acid and hydrochloric acid
solutions have been studied. Results show that corrosion law of the RE-Ni-W-P-PTFE-SiC
composite coatings in various concentrations of sulfuric acid solutions is identical. The
corrosion rates of the composite coatings are increased with increasing sulfuric acid concentration
while the corrosion rates are decreased with increasing concentration of hydrochloric acid. Anode
polarization curves of RE-Ni-W-P-SiC-PTFE composite coatings in various concentrations
of sulfuric acid and hydrochloric acid solutions have showed that anode polarization
electric current density of the composites at 200°C or 500°C heat treatment was below that
at other heat treatment, it is clear that the composite coatings at 200°C or 500°C heat
treatment has better corrosion resistance.
Advances in Residual Stress Modeling and Measurement for the Structural Integrity Assessment of Welded Thermal Power Plant
Authors: Edwards Lyndon , Smith Mike C. , Turski Mark , Fitzpatrick Michael E. , Bouchard P. John
Published: March 2009

The safe operation of both thermal and nuclear power plant is increasingly dependent
upon structural integrity assessment of pressure vessels and piping. Furthermore, structural failures
most commonly occur at welds so the accurate design and remnant life assessment of welded plant
is critical. The residual stress distribution assumed in defect assessments often has a deciding
influence on the analysis outcome, and in the absence of accurate and reliable knowledge of the
weld residual stresses, the design codes and procedures use assumptions that yield very conservative
assessments that can severely limit the economic life of some plant. However, recent advances in
both the modeling and measurement of residual stresses in welded structures and components open
up the possibility of characterising weld residual stresses in operating plant using state-of–the–art
fully validated Finite Element simulations. This paper describes research undertaken to predict
residual stresses in stainless steel welds in order to provide validated reliable, accurate Structural
Integrity assessment of nuclear power plant components
Barkhausen Noise and its Use for Quality Control of the Production of Transmission Gears
Authors: Siiriäinen Juha , Kendrish Stephen J. , Rickert Theo J. , Fix Robert M.
Published: March 2009

The use of magnetic Barkhausen Noise Analysis (BNA) has been proven to be an
effective tool for the non-destructive detection of microstructural anomalies in ferrous materials.
Used as an in-process tool for the detection of grinding burn, heat treat defects and stresses, BNA is
a quick comparative and quantitative alternative to traditional destructive methods.
Applications of BNA as a quality control tool in gear production have existed for nearly two
decades. This paper presents examples that demonstrate how BNA is used to evaluate changes in
microstructural properties. Quantitative results correlate BNA test values to X-Ray diffraction
values for the detection of changes in surface residual stress. Other quantitative analysis correlates
BNA test values to surface hardness values for the detection of re-tempering burn. Qualitative
results correlate BNA test values to acid etch patterns/colors for the detection of grinding burn
defects.
Robotically automated systems can test gear teeth and provide immediate feedback for process
control and quality assurance.
An Artificial Neural Network Approach to Plastic Collapse of Oval Boiler Tubes
Authors: Zarrabi K. , Basu A.
Published: March 2009

Boilers in power, refinery and chemical processing plants contain extensive range of tube
bends. Tube bends are manufactured by bending a straight-section tube. As a result, the crosssection
of a tube bend becomes oval. Using the finite element analysis (FEA) and artificial neural
network (ANN), the paper presents the relationships between the plastic collapse pressures and tube
bend dimensions with various degrees of ovality. It is found that as ovality increases the plastic
collapse pressure decreases. Also, the reduction of plastic collapse pressure with ovality is small for
a thick tube bend when compared with that for a thin tube bend.
Influence of Advances in Technologies for the Management of Aircraft Structural Integrity within RAAF
Authors: Janardhana Madabhushi , Davies Charles , Bowler Adam , Zemel David
Published: March 2009

The basic concept of an Aircraft Stuctural Integrity Program is to ensure that airframes
are adequately managed to ensure safe operation without catastrophic failure, to maximise fleet
availibilty and to minimise cost of ownership. In managing these three aspects, a number of
conventional and advanced technologies are being adopted and applied within the RAAF.
Composites and bonding technology has been developed and transitioned onto various RAAF
aircraft over many years in the form of Bonded Patch Repairs to airframe structures (wing and
fuselage). Based upon conventional heat treatment behaviour of aluminium alloys, Retrogressive
Re-Ageing technology is being transitioned to minimise stress corrosion cracking. From structural
mechanics and FEA technologies, Geometric Shape Optimisation methods have been applied to
minimise peak stress thresholds within aged airframe structures. To manage structural degredation
(fatigue and corrosion) a number sensor-based monitors are being developed and applied on RAAF
aircraft. Finally, using the reliability methodology, a proactive management program to assess the
extent of corrosion degradation within a whole aircraft is being instituted. This methodology is
being articulated through a new paradigm known as “Environmental Degradation Management
System – Tool Box” (EDMS-TB). Within RAAF it can be demonstrated that candidate technologies
which are adopted have direct and in-direct positive influences within ASIPs to address the key
structural integrity parameters of Safety, Availability and Cost of Ownership.
Use of the Master Curve to Investigate the Effect of Post-Weld Heat Treatment on ASTM A106B
Authors: Driessen N. , Clegg Richard E.
Published: March 2009

ASTM A106/B is commonly used for pressure piping in alumina refineries. Due to the
problem of caustic cracking in alumina refineries, piping must be stress relieved after welding,
usually through a post-weld heat treatment (PWHT) process at a temperature of 635°C. However,
multiple PWHT procedures tend to degrade the mechanical properties of steel and design standards
have set limits on the length of time PWHT can be carried out before steel should be replaced. In
this study, the effect of PWHT time on the properties of A106/B parent metal was examined, with
particular emphasis on the effect on toughness. PWHT was carried out for 1, 8 and 40 hours and
the results were compared with those for as-received material. Impact transition temperature and
room-temperature tensile results were determined using standard tests. The reference temperature,
To, was determined using ASTM E1921 with arc-shaped tension specimens. The results showed
that the ductile-to-brittle transition temperature increased significantly as PWHT time increased and
the implications of this to a fracture mechanics analysis of plant operations are discussed.
Fatigue Behaviour of Ti-6Al-4V Alloy in Vacuum and at Low Temperature
Authors: Zuo J.H. , Wang Z.G. , Han En-Hou
Published: March 2009

Investigations have been conducted on the fatigue behavior of Ti-6Al-4V alloy with the
bimodal microstructure in air at room temperature, in vacuum at room temperature and in vacuum
at low temperature (100K), respectively. The results show that the fatigue life of this alloy is longer
in vacuum and/or at low temperature than that in air at room temperature. The combination of
vacuum and low temperature can much improve the fatigue properties of this alloy because of their
purifying effect on fatigue cracks propagation. SEM observation of fatigue fracture surface
indicates that all the fatigue cracks initiate in the sample surface when Nf ≦106 cycles. The above
three testing conditions lead to different modes of fatigue crack propagation and therefore much
different morphology of fatigue fracture.
Mechanical Modelling of Wire Reinforced Metal Matrix Extrusion Profiles
Authors: Wedekind M. , Baier H.
Published: March 2009

Compound extruded unidirectionally reinforced profiles are heterogeneously
reinforced metal matrix composites. Profiles made from this material show a different
mechanical behaviour than classical composite components. Homogenized material properties
are required for an efficient design process. Within this paper an approach is shown to provide
homogenized data for stiffness and strength for compound-extruded components. The
usability of the Tsai-Hill failure criterion is investigated, and shown for cases with negligible
residual stresses. Load cases including thermal stresses cannot be investigated by the Tsai-
Hill failure criterion. Within the failure investigation a procedure is shown to include residual
and thermal stresses.
Experimental and Computational Analysis of Machining Processes for Light-Weight Aluminium Structures
Authors: Weinert Klaus , Biermann Dirk , Kersting Michael , Grünert Sven
Published: March 2009

Different possible reasons for defects have to be considered in machining light-weight
aluminum structures. In the machining process, the cutting power affecting the workpiece leads to a
thermo-mechanical load that can cause undesirable workpiece deformations and thus shape
deviations. Moreover, the microstructure and the machined surface can be influenced, which is
detrimental to the later application of the structures. Previously conducted experimental and
simulative investigations, estimated the circular milling process to be the most suitable machining
operation that provides the best compromise between mechanical and thermal loads compared to
drilling operations [1,2].
In this paper the results of machining end-cross-sections of an aluminum profile are presented. The
machining was obtained by a milling process, which is demanding, because of the low profile
stiffness. For this process it is important to know the effects of machining in view of the shape
deviations. By means of a Finite-Element-Analysis the deformations of the profile web can be
calculated as well as validated by experiments. Based on these results, the appropriate process
parameter values for end machining can be defined.
Progresses on the Fatigue Reliability Research of China Railway Vehicles in Recent Decade
Authors: Shen Zhi Yun , Zhao Yong Xiang , Yang Bing , Zhang Wei Hua
Published: March 2009

Main progresses are reviewed and prospected from four elements on the fatigue reliability
analysis research of China railway vehicles during recent decade. First, material fatigue database has
been moderately developed and an emphasis was placed on the systemized fatigue properties. Second,
a great of on-line inspections have been performed on the wheel-track contact forces and service
stresses of key structures. A reliable vehicle dynamics simulation technique has been developed for
simulating the contact forces and a multi-variable quadratic regression approach has been proposed to
calculate the service stresses for recuing imperfect inspections. Third, systemized fatigue reliability
researches have been made on improved fatigue limit measurement, probabilistic S-N curves,
scale-deduced fatigue behavior, design Goodman-Smith diagram, and reliability analysis approach to
address on the real super-long life of railway vehicle’s structures. Fourth, a critical safety state theory
is established to address the time-dependent off-round wheel wear and the interactive fatigue damage
between components. Fatigue cracking threshold measurement is improved. And a fatigue crack
growth modeling is developed to cover entire physical process from the threshold to the fracture. The
axle critical safety sizes are determined under considering the off-round wheel and the wheel critical
safety wear sizes are measured to ensure the axle expected safety life. All researches are valuable to
be further studied.
Modulus Prediction for 2D PWF Composites
Authors: Cheng Xu , Xiong Jun Jiang
Published: March 2009

This paper seeks to develop the analytical method for predicting the compression modulus
of 2D plain weave fabric (PWF) composites based on a micro-mechanical curved beam model
depicted with sinusoidal shape functions. The modulus calculations are obtained and compared with
the experiments, demonstrating that predictions correlate well with the experimental results.
Coding and Decoding of Topological Entities in Constraint-Based Variational Design
Authors: Wu Tao , Xi Yi Shan , Li Zhang , Wan Yan Ling
Published: March 2009

In top-down, constraint-based variational design environment, user expresses his design
intent through a series of construction steps that will be further transferred to design variants
maintained by the system. Persistent naming techniques build a bridge between design variants and
user design intent. The graph-based coding and decoding method together with parameter
information, presented in this paper successfully maintain the user design intent in constraint-based
variational design. Besides, the energy of parameter vector field decoding method gives a
mathematical definition on comparability between original model and regenerated model.
Radial Clearance is Key Factor Affecting Roller Bearing Life Prediction in Tri-Cone Bit
Authors: Bu Chang Gen
Published: March 2009

The life of tri-cone bits will directly affect the economic and technical drilling target. In
order to control and evaluate bit’s life, the paper builds up the calculating mathematical model, which
is suitable for determination of tri-cone bit’s life, to rationally design the radial clearance of non
standard bearings. Effect of the radial clearance on the life of roller bearing was systematically
deduced. The larger the radial clearance is; the higher the contact stress is; and the shorter the roller
bearing life is. It follows from the model that the key factor of the radial clearance should be taken into
consideration besides structure data and anti-friction pair’s heat treatment of roller bearing in order to
decrease the contact stress of anti-friction pair and prolong the bit’s life.
Research on Tolerance Analysis System Based on 3D Collaborative Design Platform
Authors: Shao Xin Yu , Lin K. , Gao Liang , Qiu Hao Bo
Published: March 2009

Computer supported collaborative work (CSCW) technology is used to solve the
resource-sharing problems in collaborative design, analysis, and manufacture. To address this need, a
system called CollabVue for collaborative product design between designers and manufacturers is
proposed in this study. This paper first introduces the framework of tolerance analysis system based
on CollabVue, and then discusses the utilization of geometric topology information in 3D model to
resolve the problem of dimension information input and the related specific operations. Based on
object-oriented technology, a new data structure to interactively pick up and store dimension
information is established. Finally the model uses iterative method to compute technological
dimension chain equation.
Dynamic Reliability Sensitivity Analysis of Torsion Bar
Authors: Wang Xin Gang , Zhang Yi Min , Yan Y.F. , Wang Bao Yan
Published: March 2009

In this paper, the variation rules of strength, load, reliability and failure rate of mechanical
components are studied with time, and a state equation model for dynamic reliability of mechanical
components is established under random load. Meanwhile, reliability index is obtained by using
Second moment method and perturbation method. Based on the reliability design theory and
sensitivity analysis method, torsion-bar is taken as an example, and the dynamic reliability sensitivity
of torsion-bar is extensively discussed and a computing method is presented for dynamic reliability
sensitivity design. The variation rules of dynamic reliability sensitivity are obtained and the effects of
design parameters on reliability of torsion-bar are studied. As a result, the proposed method provides
theoretical basis for reliability design of torsion bar.
Destroy Probability of Ship Defensive Structure Subjected to Underwater Contact Explosions
Authors: Zhang Jing , Shi Xing Hua , Xu Ding Hai , Wang Shan
Published: March 2009

The reliability of ship defensive structure subjected to underwater contact explosions is
important both in theory and engineering. Because of the complex response of structure under
explosions in which the fluid-structure-interaction should be considered, the problem under
discussion could not be solved by analytical method. The Monte Carlo combined with FEM method
is used to solve this problem in this paper. The samples of basic random variables that are dynamite
density, the elastic modulus and ultimate strength of plate material are generated by the random
number generate program. Then, with these samples, the simulations of multilayer plate-shell
structure subjected to underwater contact explosions are done by LS-DYNA, and the maximum
stress of each plate is obtained, which should be validated to obey the normal distribution. Based on
the intensity rule, the destroy index is introduced in this paper, then the destroy probability of each
plate and system are calculated using the basic theory of reliability.
Determination of the Maintenance Tasks for Aircraft Structural Significant Items Based on CBR Method
Authors: Geng Duan Yang
Published: March 2009

Based on the CBR technique and the characteristics of developing corrosion inspection
tasks and intervals of aircraft structural items, a new method which can determine the initial
scheduled preventive maintenance tasks and intervals of aircraft structural items is given, and is
implemented by the tools of object -oriented program design method and visual C++ language.
Finally, an example of wing assembly of some model of aircraft in china is given in order to validate
the feasibility of this system. The results indicate that the CBR-MTI system can establish the
maintenance tasks and intervals quickly, and its consequences are more consistent with the actual
situation because all maintenance tasks and intervals in the case-base have been validated by the
actual operation of other aircraft.
Power Train-Vehicle Modeling to Simulate Shifting Transients of Off-Highway Vehicles
Authors: Mou Liu Chen , Yin Guang Fu
Published: March 2009

Analytic modeling and analog computer simulation techniques are presented to determine
the power train transient responses excited by clutch-actuated gear shifts. A method to describe the
dynamics of a transmission arrangement having several clutches and interconnected planetary gear
sets is considered in detail. Simulation model testing is directed toward optimizing system design
parameters and evaluating power train component capability and vehicle shift-feel. Data reduction
techniques applied to model responses of torque and speed will yield appropriate spectrums
representative of simulated work cycle.
Design of Personal Positioning for Coal Mine Based on Mesh
Authors: Gao Wen Hua , Ma J. , Kang L.
Published: March 2009

This paper puts forward a method for a location system for colliery worker based on
wireless mesh network combined with zigbee technology which supports IEEE 802.15.4 wireless
communication standard, with low power dissipation. Data receipt and transmission by wireless
communication is realized by RF chip MC13192 produced by Freescale company. Data procession
and analysis is achieved by S3C2410A chip manufactured by Sumsung which belongs to ARM9
16/32 RISC processor.
Numerical Simulation of Fuel Processor for Fuel Cell Vehicles
Authors: Li Cong , Wu Xun Cheng , Jiang Lei
Published: March 2009

In this paper, a two-dimensional mathematical model of a processor for fuel cell vehicles
was presented in order to predict the effect of the parameters on the hydrogen content of the processor.
The structure of the processor and the operating parameters were taken into account in the model. The
complex physical and chemical process in the processor of dimethyl ether partial oxidation was well
described by this model. The mathematical model was introduced into the commercial software
star-cd, and then numerical simulations were also performed based on this model. In order to
accounting for the effect of the processor temperature and volume fraction field, TGrid mesh method
and laminar flow model were selected. Experimental verification of the two-dimensional
mathematical model was implemented on self-designed equipment. The result indicates that the
computed data is in good agreement with the experiment one. Finally, on the basis of the
mathematical model, the effect of the parameters on the hydrogen content of the processor were
investigated.
Fatigue Life Prediction of a Railway Bogie Frame
Authors: Deng Rui , Zhai W.M. , Xiao Shou Ne
Published: March 2009

A fatigue life prediction method was introduced. The method was based on the
combination of time domain and frequency domain method. Dynamic model of a complete railway
locomotive system was established using SIMPACK software. The dynamic load histories acting on
the bogie frame can be obtained by the Multi-Body System (MBS) analysis technique with time
integration. FEM model of the bogie frame was established by applying ANSYS software. The
natural frequencies and mode shapes of the frame were calculated and the dangerous nodes in the
critical location were determined using the modal analysis technique. The stresses in dangerous nodes
were calculated with the quasi-static stress/strain technology. PSD of the stresses was generated using
the Fast Fourier Transformation (FFT). Fatigue life of the bogie frame was evaluated with the Dirlik’s
formulation. Results showed that the calculated life of the analyzed bogie frame could meet the design
requirement.
A New Approach for Multi-Criteria ABC Analysis
Authors: Jiang R. , Yuan Xiao Na
Published: March 2009

Manufacturing enterprises need to manage many inventory items. To effectively manage
the inventory, a usual practice is to classify the inventory items into several groups and use different
management strategies for the items in different groups. ABC classification has been widely used,
and has evolved into various multi-criteria classification schemes. Recently, a few multi-criteria
ABC classification approaches using variable weights appeared in the literature. This paper analyzes
their properties and proposes an improved approach. A numerical example is included to illustrate
the appropriateness of the proposed approach.