D.Eylon
,
S.R.Seagle
材料科学技术（英文）
The state of Ti research, development and industry is reviewed in this article. The fifty-year anniversary of Ti technology commercialization in the USA provides an opportunity for a historical perspective. Incorporation of "information-age" tools into alloy development, processing, and production invigorates the technology. Consolidation, diversification and globalization have been transforming the Ti industry in the recent years.
关键词:
H.-M. Huang
,
J. Pan and S. C. Tang 1) Mechanical Engineering and Applied Mechanics
,
The University of Michigan Ann Arbor
,
MI 48109
,
USA 2) Ford Research Laboratory
,
Ford Motor Company Dearborn
,
MI 48121
,
USA
金属学报(英文版)
An approximate macroscopic yield criterion for anisotropic porous sheet metals is adopted in a failure prediction methodology that can be used to investigate the failure of sheet metals under forming operations. This failure prediction methodology is developed based on the Marciniak-Kuczynski approach by assuming a slightly higher void volume fraction inside randomly oriented imperfecte analysis. Here, a nonproportional deformation history including relative rotation of principal stretch directions is identified in a selected critical element of an aluminum sheet from a FEM fender forming simulation. Based on the failure prediction methodology, the failure of the critical sheet element is investigated under the non-proportional deformation history. The results show that thiven non-proportional deformation history.
关键词:
sheet metal forming
,
null
,
null
,
null
HE Youduo
,
Baotou Institute of Iron and Steel Technology
,
Baotou
,
ChinaY.SAHAI
,
The Ohio State University
,
USA
金属学报(英文版)
A mathematical model to represent the fluid flow, temperature distribution and mass transfer in CVD reactors has been developed. The model is used to predict the velocity, temperature, and molar concentration profiles in the tapered annulus of a reactor for silicon deposition from SiCl_4 in H_2. Results of the investigation contribute to the understanding of the transport pro- cesses involved in such a system. The model can also be used for optimizing the design parameters, such as inlet flow rate, susceptor tilt angle, etc.
关键词:
reactor of chemical vapor deposition
,
null
,
null
,
null
Corrosion Reviews
The corrosion field experienced a rapid growth in knowledge and innovations in the last decade. In this paper, a bibliometric analysis was applied to evaluate the global scientific production of corrosion papers (46,384 pieces) front 1992 to 2007 in all journals of all the subject categories of the Science Citation Index Expanded (SCIE) compiled by the Institute for Scientific Information (ISI), Philadelphia, USA. The analysis of the published Outputs showed that research on corrosion increased steadily over the past 16 years and the researchers from the EU, the USA and China contributed greatly to the rise in publications. Synthetically analyzing the information including international cooperation, subject category, distribution Of journals, document type, document language and author keywords, the development of corrosion research over the past 16 years has been visualized and several key findings were provided. This bibliometric method can help relevant researchers realize the panorama of global corrosion research, and establish the further research direction.
关键词:
Corrosion;Bibliometrics;Research trends
Journal of Solid State Chemistry
A new compound, beta-SrGaBO4, has been attained through solid phase transition from alpha-SrGaBO4 at high temperatures. Its crystal structure has been determined from powder X-ray diffraction data by direct methods. The refinement was carried out using the Rietveld method and the final refinement converged with Rp = 11.42 % and Rwp = 15.16 %. It has an orthorhombic P2(1)2(1)2 space group with cell parameters a = 15.3706(2) Angstrom b = 8.992 1 (1) Angstrom, c = 5.919 1 (1) A, and Z = 8. The structure of beta-SrGaBO4 is built up from Ga2BO8 units formed by two GaO4 tetrahedra and one BO3 triangle, and Sr2O12 units formed by two SrO7 groups. Tetrahedra [GaO4] are linked by shared O(3) and O(7) atoms to form infinite chains along the e axis. (C) 2002 Elsevier Science, (USA).
关键词:
beta-SrGaBO4;borate;structure determination;X-ray powder diffraction;crystal-structure
Composites Science and Technology
The thermal expansion of the reference sample, pure copper film in the temperature range of - 120 to 200 degrees C was first measured using the newly improved CCD imaging technique for measurement of thermal expansion of thin films. The results showed good accordance with the recommended data given by TPRC (Thermophysical Properties Research Centre, USA) handbook, verifying that the present method is valid for measuring thermal expansion of films. Then, the thermal expansion TE (Delta L/L-0) of silica/polyimide composite films with different SiO2 fractions i.e. 0, 1, 3, 5, 8, 10 and 15 wt% prepared using the sol-gel technique was obtained in the temperature range of - 120 to 200 degrees C using the newly improved CCD method and the differential coefficient thermal expansion (CTE) can be deduced by Delta L/L-0 similar to temperature relation. The CTE Of SiO2/PI Composite films decreased with the increase Of SiO2 content and the decrease of temperature. An empirical equation of CTE of SiO2/PI with SiO2, content has been given in this paper. (C) 2007 Elsevier Ltd. All rights reserved.
关键词:
silica/polyimide composite film;thermal expansion;CCD imaging;technique;low temperature;elevated temperature;mechanical-properties;cryogenic properties;nanocomposite films;polyimide films;low-temperature;silica
Journal of Solid State Chemistry
The subsolidus phase relations of R2O3-CaO-CuO ternary systems (R = Nd, Sm, Gd, Tm) have been investigated by X-ray powder diffraction. All samples were synthesized at about 950degrees in air. There exists a ternary compound Ca14-xRxCu24O41 (x = 4 for R = Nd, Gd and x = 5 for R = Sm) and a ternary solid solution Ca2+xR2-xCu5O10 (R = Nd, Sm, Gd, Tm) with a wide composition range Deltax of about 0.6. The compound Ca14-xRxCu24O41 possesses a layered orthorhombic structure and is isostructural to Sr14-xCaxCu24O41. The lattice parameters a and c of the compound are basically independent of the ionic radius of R, while the lattice parameter b and unit-cell volume V decrease substantially with the decrease of the ionic radii of R. The Ca2+xR2-xCu5O10 solid solution is isostructural to Ca2+xY2-xCu5O10, the structure of which is based on an orthorhombic "NaCuO2-type" subcell containing infinite one-dimensional chains of edge-shared square planar cuprate groups crosslinked by the layered cations Ca and R that locate in the inter-chain tunnels. (C) 2002 Elsevier Science (USA). All rights reserved.
关键词:
R2O3-CaO-CuO (R = Nd, Sm, Gd, Tm) systems;phase relations;Ca10R4Cu24O41 (R = Nd, Sm, Gd) structure;Ca2+xR2-xCu5O10 (R = Nd, Sm,;Gd, Tm) structure;ternary-system;approximately 950-degrees-c;high-pressure;superconductivity;diagram;air;er;compatibilities;property;oxide
