The Experts below are selected from a list of 30300 Experts worldwide ranked by ideXlab platform
Akihisa Inoue - One of the best experts on this subject based on the ideXlab platform.
-
rapid degradation of azo dye by fe based Metallic Glass powder
Advanced Functional Materials, 2012Co-Authors: Junqiang Wang, Mingwei Chen, Dmitri V Louzguineluzgin, John H. Perepezko, Akihisa InoueAbstract:The outstanding efficiency of Fe-based Metallic Glass powders in degrading organic water contaminants is reported. While the Glassy alloy contains 24% chemically inactive metalloid elements, the powders are capable to completely decompose the C32H20N6Na4O14S4 azo dye in aqueous solution in short time, about 200 times faster than the conventional Fe powders. The metastable thermodynamic nature and the particle surface topography are the major factors controlling the chemical performance of the Metallic Glass. Our findings may open a new opportunity for functional applications of Metallic Glasses.
-
formation of Metallic Glass nanowires by gas atomization
Nano Letters, 2012Co-Authors: Koji S Nakayama, Na Chen, Yoshihiko Yokoyama, Takeshi Wada, Akihisa InoueAbstract:Gas atomization which is a conventional technique in powder metallurgy is adapted for the formation of Metallic Glass nanowires. This approach is able to produce a large quantity of nanowires with diameters in the 50–2000 nm range. Experiments performed with different conditions and alloy compositions confirm that the key mechanism of the nanowire formation is the spinnability which increases exponentially when the melt stream is supercooled from the liquid state.
-
strong and light metal matrix composites with Metallic Glass particulate reinforcement
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2012Co-Authors: M. Aljerf, Dmitri V Louzguineluzgin, Akihisa Inoue, K. Georgarakis, A.r. Yavari, Le A MoulecAbstract:Abstract A new Al 6061 alloy composite reinforced with [(Fe 1/2 Co 1/2 ) 75 B 20 Si 5 ] 96 Nb 4 Metallic Glass was produced by sintering at a temperature between the Glass transition ( T g ) and crystallization temperature ( T x ) of the Metallic Glass and close to the melting temperature of the Al alloy. At this temperature range (Δ T x = T x − T g ), the Metallic Glass particles exhibit viscous behavior, resulting in composites with low or zero porosity. The use of the Glassy particles as reinforcement led to significant strengthening of the Al matrix alloy while retaining a plastic strain before fracture of about 13% leading to a remarkable combination of high strength and plasticity. Because Metallic Glasses are much harder than Al matrix alloys, when strain is applied to the composite, plastic deformation occurs in the matrix while the Glassy particles deform only elastically.
-
direct observation of local atomic order in a Metallic Glass
Nature Materials, 2011Co-Authors: Akihiko Hirata, Yoshihiko Hirotsu, Pengfei Guan, Takeshi Fujita, Alain Reza Yavari, Toshio Sakurai, Akihisa Inoue, Mingwei ChenAbstract:The atomic configuration of Metallic Glasses is a long-standing issue important to the understanding of their properties. Nanobeam electron diffraction experiments now enable a direct determination of the local atomic order in a Metallic Glass. The determination of the atomic configuration of Metallic Glasses is a long-standing problem in materials science and solid-state physics1,2. So far, only average structural information derived from diffraction and spectroscopic methods has been obtained. Although various atomic models have been proposed in the past fifty years3,4,5,6,7,8, a direct observation of the local atomic structure in disordered materials has not been achieved. Here we report local atomic configurations of a Metallic Glass investigated by nanobeam electron diffraction combined with ab initio molecular dynamics simulation. Distinct diffraction patterns from individual atomic clusters and their assemblies, which have been theoretically predicted as short- and medium-range order6,7,8, can be experimentally observed. This study provides compelling evidence of the local atomic order in the disordered material and has important implications in understanding the atomic mechanisms of Metallic-Glass formation and properties.
-
effect of spraying condition on property of zr based Metallic Glass coating by gas tunnel type plasma spraying
Materials Science and Engineering B-advanced Functional Solid-state Materials, 2010Co-Authors: Akira Kobayashi, Toshio Kuroda, Hisamichi Kimura, Akihisa InoueAbstract:Abstract Metallic Glass has excellent functions such as high strength and high corrosion resistance. However, as Metallic Glass is expensive, a composite material is preferred for better cost performance. Thermal spraying is one of the potential candidates to produce such Metallic Glass composites. Gas tunnel type plasma spraying is useful in obtaining high quality ceramic coatings because it can easily control the condition of spraying powder. In this study, Zr-based Metallic Glass (Zr55–Cu30–Al10–Ni5) coatings were produced by gas tunnel type plasma spraying, and the effect of spraying conditions on the properties of Zr-based Metallic Glass coating was investigated. Dense Zr-based Metallic Glass coatings of more than 200 μm in thickness were prepared with a Vickers hardness of about Hv = 550 at a plasma current of 250 A, and the amorphous phase of this Metallic Glass coating appeared to remain in good condition.
William L Johnson - One of the best experts on this subject based on the ideXlab platform.
-
Designing color in Metallic Glass
Scientific Reports, 2019Co-Authors: Jong Hyun Na, Maximilien Launey, Glenn Garrett, Marios D Demetriou, William L JohnsonAbstract:“Designing” Metallic Glasses to exhibit properties beyond those offered within the narrow composition ranges where Glass formation is possible poses a formidable scientific challenge. This challenge may be tackled by forming composite structures comprising a Metallic Glass matrix and homogeneously precipitated dendrites, known as “Metallic Glass matrix composites” (MGMCs). In principle, MGMCs can be designed to exploit the attractive performance characteristics of the Metallic Glass while alleviating its negative undesirable attributes. In this work we introduce a MGMC development concept for designing color in Metallic Glass. MGMCs consisting of a white-gold Metallic Glass matrix with finely dispersed yellow-gold microdendrites are explored. A series of gold MGMCs is developed displaying uniform and visually-unresolved yellow colors over a broad range of chromaticity, along with high overall hardness. This design concept paves the way for the development of a new generation of metal alloys that combine advanced engineering performance with attractive cosmetic attributes.
-
new processing possibilities for highly toughened Metallic Glass matrix composites with tensile ductility
Scripta Materialia, 2008Co-Authors: Douglas C Hofmann, Jinyoo Suh, Aaron Wiest, William L JohnsonAbstract:New processing possibilities are explored for a semi-solidly-processed bulk Metallic Glass matrix composite based on the ZrTiNbCuBe system. Thermoplastic processing in the supercooled liquid region, extensive room temperature cold-rolling, and tensile ductility with work-hardening are all achieved. This research demonstrates that bulk Metallic Glass matrix composites have potential that far exceeds high tensile ductility and ultra-high toughness.
-
processing microstructure and properties of ductile metal particulate reinforced zr57nb5al10cu15 4ni12 6 bulk Metallic Glass composites
Acta Materialia, 2002Co-Authors: Haein Choiyim, R D Conner, Frigyes Szuecs, William L JohnsonAbstract:The Zr57Nb5Al10Cu15.4Ni12.6 bulk Metallic Glass forming liquid is reinforced with up to 50 Volume-percent (% Vf) Ta, Nb, or Mo particles. An extensive reaction layer of varying composition formed in the Metallic–Glass matrix surrounding the particles. A characterization based on X-ray diffraction, differential scanning calorimeter, electron microprobe, and scanning electron microscopy is presented. The composites were tested in compression and tension. Compressive strain-to-failure increased by up to a factor of 12 compared to the unreinforced Zr57Nb5Al10Cu15.4Ni12.6 bulk Metallic Glass. The increase in compressive strain-to-failure is due to the particles restricting shear band propagation, promoting the generation of multiple shear bands and additional fracture surface area.
-
quasistatic and dynamic deformation of tungsten reinforced zr57nb5al10cu15 4ni12 6 bulk Metallic Glass matrix composites
Scripta Materialia, 2001Co-Authors: Haein Choiyim, Robert D. Conner, Frigyes Szuecs, William L JohnsonAbstract:Quasistatic and dynamic deformation behavior of composites of Zr57Nb5Al10Cu15.4Ni12.6 Metallic Glass reinforced with tungsten is studied. The plastic deformation of the Metallic Glass was increased under quasistatic compression in composites. Localized shear band failure of these composites results in self-sharpening behavior during ballistic impact.
-
Fracture toughness determination for a beryllium-bearing bulk Metallic Glass
Scripta Materialia, 1997Co-Authors: Robert D. Conner, Ares J. Rosakis, William L Johnson, David M OwenAbstract:A class of beryllium-bearing bulk Metallic Glass alloys has recently been developed at the California Institute of Technology. These alloys can be fabricated in the form of large ingots with minimum dimensions on the order of centimeters, which allows valid mechanical tests to be performed on these materials. Such tests were not formerly possible given the small dimensions of earlier Metallic Glass specimens. Some basic physical and mechanical properties have been measured on specific beryllium-bearing bulk Metallic Glass with a nominal composition of Zr{sub 41.25}Ti{sub 13.75}Cu{sub 12.5}Ni{sub 10}Be{sub 2.5}, by the authors and some of their co-workers. The purpose of this paper is to report on the first ever direct measurement of the fracture toughness of any bulk Metallic Glass system.
Akira Kobayashi - One of the best experts on this subject based on the ideXlab platform.
-
effect of spraying condition on property of zr based Metallic Glass coating by gas tunnel type plasma spraying
Materials Science and Engineering B-advanced Functional Solid-state Materials, 2010Co-Authors: Akira Kobayashi, Toshio Kuroda, Hisamichi Kimura, Akihisa InoueAbstract:Abstract Metallic Glass has excellent functions such as high strength and high corrosion resistance. However, as Metallic Glass is expensive, a composite material is preferred for better cost performance. Thermal spraying is one of the potential candidates to produce such Metallic Glass composites. Gas tunnel type plasma spraying is useful in obtaining high quality ceramic coatings because it can easily control the condition of spraying powder. In this study, Zr-based Metallic Glass (Zr55–Cu30–Al10–Ni5) coatings were produced by gas tunnel type plasma spraying, and the effect of spraying conditions on the properties of Zr-based Metallic Glass coating was investigated. Dense Zr-based Metallic Glass coatings of more than 200 μm in thickness were prepared with a Vickers hardness of about Hv = 550 at a plasma current of 250 A, and the amorphous phase of this Metallic Glass coating appeared to remain in good condition.
-
mechanical properties and microstructure of plasma sprayed ni based Metallic Glass coating
NEW TREND IN APPLIED PLASMA SCIENCE AND TECHNOLOGY: The Seventh International Symposium on Applied Plasma Science, 2010Co-Authors: Akira Kobayashi, Toshio Kuroda, Hisamichi Kimura, Akihisa InoueAbstract:Various developmental research works on the Metallic Glass have been conducted in order to broaden its application field. Thermal spraying method is one of the potential techniques to enhance the excellent properties such as high toughness and corrosion resistance of the Metallic Glass material. The gas tunnel type plasma spraying is useful to obtain high quality ceramic coatings such as Al2O3 and ZrO2 coatings. In this study, the Ni‐based Metallic Glass coatings were produced by the gas tunnel type plasma spraying under various experimental conditions, and their microstructure and mechanical properties were investigated. At the plasma current of 200–300 A, the Ni‐based Metallic Glass coatings of more than 200 μm in thickness were formed densely with Vickers hardness of about Hv = 600.
-
mechanical property of fe base Metallic Glass coating formed by gas tunnel type plasma spraying
Surface & Coatings Technology, 2008Co-Authors: Akira Kobayashi, Shoji Yano, Hisamichi Kimura, Akihisa InoueAbstract:Abstract Metallic Glass has excellent functions such as high toughness and corrosion resistance. Therefore it is one of the most attractive materials, and many researchers have conducted various developmental research works. However, the Metallic Glass material is expensive and a composite material is preferred for the industrial application. Thermal spraying method is one of potential candidates to produce Metallic Glass composites. The gas tunnel type plasma system, which has high energy density and efficiency, is useful for smart plasma processing to obtain high quality ceramic coatings such as alumina (Al 2 O 3 ) and zirconia (ZrO 2 ) coatings. Also, the gas tunnel type plasma spraying can produce Metallic Glass coatings. In this study, the Fe-base Metallic Glass coatings were formed on the stainless-steel substrate by the gas tunnel type plasma spraying, and the microstructure and mechanical property were investigated. The Fe-base Metallic Glass coatings of about 200 μm in thickness were dense with a Vickers hardness of about Hv = 1100 at plasma current of 300 A. The abrasive wear resistance of Fe-base Metallic Glass coating was higher than the SUS substrate.
-
Fe-based Metallic Glass coatings produced by smart plasma spraying process
Materials Science and Engineering B-advanced Functional Solid-state Materials, 2008Co-Authors: Akira Kobayashi, Shoji Yano, Hisamichi Kimura, Akihisa InoueAbstract:Abstract Metallic Glass has excellent functions such as high toughness and corrosion resistance. Therefore it is one of the most attractive materials, and many researchers have conducted various developmental research works. However, the Metallic Glass material is expensive and a composite material is preferred for the industrial application. Thermal spraying method is a potential candidate to produce Metallic Glass composites. The gas tunnel type plasma system is useful for smart plasma processing to obtain high quality ceramic coatings such as alumina (Al2O3) and zirconia (ZrO2) coatings. Also, the gas tunnel type plasma spraying can produce Metallic Glass coatings. In this study, the Fe-based Metallic Glass coatings were produced by gas tunnel type plasma spraying, and the microstructure and some properties were investigated. The amorphous phase of this Metallic Glass coating was confirmed by the XRD method. The Fe-based Metallic Glass coatings of about 200 μm in thickness were dense with a Vickers hardness of about Hv = 1100 at plasma current of 300 A.
Hisamichi Kimura - One of the best experts on this subject based on the ideXlab platform.
-
effect of spraying condition on property of zr based Metallic Glass coating by gas tunnel type plasma spraying
Materials Science and Engineering B-advanced Functional Solid-state Materials, 2010Co-Authors: Akira Kobayashi, Toshio Kuroda, Hisamichi Kimura, Akihisa InoueAbstract:Abstract Metallic Glass has excellent functions such as high strength and high corrosion resistance. However, as Metallic Glass is expensive, a composite material is preferred for better cost performance. Thermal spraying is one of the potential candidates to produce such Metallic Glass composites. Gas tunnel type plasma spraying is useful in obtaining high quality ceramic coatings because it can easily control the condition of spraying powder. In this study, Zr-based Metallic Glass (Zr55–Cu30–Al10–Ni5) coatings were produced by gas tunnel type plasma spraying, and the effect of spraying conditions on the properties of Zr-based Metallic Glass coating was investigated. Dense Zr-based Metallic Glass coatings of more than 200 μm in thickness were prepared with a Vickers hardness of about Hv = 550 at a plasma current of 250 A, and the amorphous phase of this Metallic Glass coating appeared to remain in good condition.
-
mechanical properties and microstructure of plasma sprayed ni based Metallic Glass coating
NEW TREND IN APPLIED PLASMA SCIENCE AND TECHNOLOGY: The Seventh International Symposium on Applied Plasma Science, 2010Co-Authors: Akira Kobayashi, Toshio Kuroda, Hisamichi Kimura, Akihisa InoueAbstract:Various developmental research works on the Metallic Glass have been conducted in order to broaden its application field. Thermal spraying method is one of the potential techniques to enhance the excellent properties such as high toughness and corrosion resistance of the Metallic Glass material. The gas tunnel type plasma spraying is useful to obtain high quality ceramic coatings such as Al2O3 and ZrO2 coatings. In this study, the Ni‐based Metallic Glass coatings were produced by the gas tunnel type plasma spraying under various experimental conditions, and their microstructure and mechanical properties were investigated. At the plasma current of 200–300 A, the Ni‐based Metallic Glass coatings of more than 200 μm in thickness were formed densely with Vickers hardness of about Hv = 600.
-
formation of rosette like nanopatterns by selective corrosion of Metallic Glass
Japanese Journal of Applied Physics, 2008Co-Authors: Wei Zhang, Hisamichi Kimura, Akihiko Inoue, T Sakurai, Mingwei ChenAbstract:Cu nanostructured patterns were spontaneously generated by the selective corrosion of CuZr Metallic Glass ribbons. Free corrosion of Glassy CuZr ribbons in dilute HCl leads to the selective dissolution of Zr atoms from the Glassy substrate and leaves behind nanocrystalline Cu with self-assembled patterns. This study may lead to the development of a facile approach to synthesizing nanostructured architectures with well-defined patterns by manipulating the corrosion process of Metallic Glass.
-
micro flash welding of super duplex stainless steel with zr Metallic Glass insert
Materials Science Forum, 2008Co-Authors: Toshio Kuroda, Masahiro Shimada, Kenji Ikeuchi, Akihisa Inoue, Hisamichi KimuraAbstract:Micro flash butt welding of super duplex stainless steel with Zr-based Metallic Glass insert was carried out using the temperature controlling system. Zr55Cu30Ni5Al10 of Zr-based Metallic Glass with thickness of 0.05mm and Zr metal with thickness of 0.1mm and 0.5 mm were used as the insert materials, in order to improve weldability. The specimens were mounted on the dies using a Gleeble thermal simulator, and then, flash butt welding was made. After welding, Zrbased Metallic Glass insert became much thinner than Zr metal insert. The super-cooled liquid in the interface protruded outside due to the superplastic deformation. The formation of the protrusion discharged the oxide films on the butting surfaces and contact surface; resulting in metallurgical bonding through the fresh surfaces. The Fe-Zr Metallic compound for Zr-based Metallic Glass insert was hardly observed. The micro flash butt welding with Metallic Glass insert was successfully accomplished for super duplex stainless steel.
-
mechanical property of fe base Metallic Glass coating formed by gas tunnel type plasma spraying
Surface & Coatings Technology, 2008Co-Authors: Akira Kobayashi, Shoji Yano, Hisamichi Kimura, Akihisa InoueAbstract:Abstract Metallic Glass has excellent functions such as high toughness and corrosion resistance. Therefore it is one of the most attractive materials, and many researchers have conducted various developmental research works. However, the Metallic Glass material is expensive and a composite material is preferred for the industrial application. Thermal spraying method is one of potential candidates to produce Metallic Glass composites. The gas tunnel type plasma system, which has high energy density and efficiency, is useful for smart plasma processing to obtain high quality ceramic coatings such as alumina (Al 2 O 3 ) and zirconia (ZrO 2 ) coatings. Also, the gas tunnel type plasma spraying can produce Metallic Glass coatings. In this study, the Fe-base Metallic Glass coatings were formed on the stainless-steel substrate by the gas tunnel type plasma spraying, and the microstructure and mechanical property were investigated. The Fe-base Metallic Glass coatings of about 200 μm in thickness were dense with a Vickers hardness of about Hv = 1100 at plasma current of 300 A. The abrasive wear resistance of Fe-base Metallic Glass coating was higher than the SUS substrate.
J Eckert - One of the best experts on this subject based on the ideXlab platform.
-
structure property relationships in shape memory Metallic Glass composites
Materials, 2019Co-Authors: Xudong Yuan, D şopu, Franco Moitzi, M Stoica, J EckertAbstract:Metallic Glass composites with shape memory crystals show enhanced plasticity and work-hardening capability. We investigate the influence of various critical structural aspects such as, the density of crystalline precipitates, their distribution and size, and the structural features and intrinsic properties of the phase on the deformation behavior of Metallic amorphous Cu 64 Zr 36 composites with B2 CuZr inclusions using molecular dynamics simulations. We find that a low density of small B2 inclusions with spacing smaller than the critical shear band length controls the formation and distribution of plastic zones in the composite and hinders the formation of critical shear bands. When the free path for shearing allows the formation of mature shear bands a high volume fraction of large B2 precipitates is necessary to stabilize the shear flow and avoid runaway instability. Additionally, we also investigate the deformation mechanism of composites with pure copper crystals for comparison, in order to understand the superior mechanical properties of Metallic Glass composites with shape memory crystals in more detail. The complex and competing mechanisms of deformation occurring in shape memory Metallic Glass composites allow this class of materials to sustain large tensile deformation, even though only a low-volume fraction of crystalline inclusions is present.
-
shear avalanches in plastic deformation of a Metallic Glass composite
International Journal of Plasticity, 2016Co-Authors: X Tong, Karin A. Dahmen, P K Liaw, G Wang, Jianzhuang Ren, S Pauly, Yulai Gao, Qijie Zhai, N Mattern, J EckertAbstract:Abstract Changes in intermittent shear avalanches during plastic deformation of a Cu 50 Zr 45 Ti 5 (atomic percent) alloy in response to variant structures including fully Glassy phase and/or nanocrystal/Glass binary phase are investigated. Second crystalline phases are introduced into the Glassy-phase matrix of a Cu 50 Zr 45 Ti 5 Metallic Glass to interfere with the shear-avalanche process, which can release the shear–strain concentration, and then tune the critically-dynamic behavior of the shear avalanche. By combining microstructural observations of the nanocrystals with the statistical analysis of the corresponding deformation behavior, we determine the statistic distribution of shear-avalanche sizes during plastic deformation, and established its dependence on the geometric distribution of nanocrystals. The scaling behavior of the distribution of shear-avalanche sizes follows a power–law relation accompanied by an exponentially-decaying scaling function in the pure Metallic Glass, and the Metallic Glass containing the small nanocrystals, which can be described by the mean-field theory. The large shear-avalanche events are dominated by structural tuning-parameters, i.e., the resistance of shear banding, and the size and volume fraction of the second crystalline phase in Metallic Glasses.
-
nanocrystallization at shear bands in bulk Metallic Glass matrix composites
Scripta Materialia, 2008Co-Authors: M H Lee, Won Tae Kim, Dong Hyun Bae, Do Hyang Kim, D J Sordelet, Ki Buem Kim, J EckertAbstract:We investigated the effect of reinforcement on the formation of nanocrystals at shear bands in a Ni-based Metallic Glass matrix composite in comparison with monolithic Ni-based bulk Metallic Glass when shear bands are generated during deformation. The results suggest that the occurrence of nanocrystallization at a shear band implies a stress concentration by a geometrical effect of the reinforcement phase on the compressive loading conditions.
-
Fracture surface morphology of compressed bulk Metallic Glass-matrix-composites and bulk Metallic Glass
Intermetallics, 2006Co-Authors: M. Kusy, J Eckert, L Schultz, Uta Kühn, A. Concustell, Annett Gebert, Jayanta Das, Maria Dolores BaróAbstract:Abstract The fracture morphology of Zr-based bulk Metallic Glass-matrix-composites (BMGCs) and Cu-based bulk Metallic Glass (BMG) after compression testing has been studied. The quasi-static compression fracture surface displays a mixture of three different distinct patterns: vein-like, smooth featureless and river-like features. The last one corresponds to the morphology known from tensile tests of BMGs. Moreover, randomly distributed transversal steps on the fracture plane are also present. This is in contrast to previous studies where a characteristic vein-like pattern is considered a unique feature of the fracture of BMGs under quasi-static uniaxial compression. The presence of different fracture features indicates that the development of the fracture plane occurs in a stepwise mode.
-
difference in compressive and tensile fracture mechanisms of zr59cu20al10ni8ti3 bulk Metallic Glass
Acta Materialia, 2003Co-Authors: Zhefeng Zhang, J Eckert, L SchultzAbstract:The compressive and tensile deformation, as well as the fracture behavior of a Zr59Cu20Al10Ni8Ti3 bulk Metallic Glass were investigated. It was found that under compressive loading, the Metallic Glass displays some plasticity before fracture. The fracture is mainly localized on one major shear band and the compressive fracture angle, theta(C), between the stress axis and the fracture plane is 43degrees. Under tensile loading, the material always displays brittle fracture without yielding. The tensile fracture stress, sigma(F)(T), is about 1.58 GPa, which is lower than the compressive fracture stress, sigma(F)(C)( = 1.69 GPa). The tensile fracture angle, sigma(F)(T), between the stress axis and the fracture plane is equal to 54degrees. Therefore, both theta(C) and theta(T) deviate from the maximum shear stress plane (45degrees), indicating that the fracture behavior of the Metallic Glass under compressive and tensile load does not follow the von Mises criterion. Scanning electron microscope observations reveal that the compressive fracture surfaces of the Metallic Glass mainly consist of a vein-like structure. A combined feature of veins and some radiate cores was observed on the tensile fracture surfaces. Based on these results, the fracture mechanisms of Metallic Glass are discussed by taking the effect of normal stress on the fracture process into account. It is proposed that tensile fracture first originates from the radiate cores induced by the normal stress, then propagates mainly driven by shear stress, leading to the formation of the combined fracture feature. In contrast, the compressive fracture of Metallic Glass is mainly controlled by the shear stress. It is suggested that the deviation of theta(C) and theta(T) from 45degrees can be attributed to a combined effect of the normal and shear stresses on the fracture plane. (C) 2002 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved.
