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141.
K V S Rama Rao 《Bulletin of Materials Science》1993,16(6):491-499
Pseudobinary alloy, Tb0·27Dy0·73Fe2−δ
, belonging to C-15 cubic Laves phase having MgCu2-type structure, possesses large magnetostriction and high magnetomechanical coupling coefficient. The advantages of this
material over existing piezoelectric materials, particularly for SONAR applications, are highlighted. Recent results on the
influence of cobalt (Co) on magnetic and magnetomechanical properties of Tb0·27Dy0·73Fe2 are discussed. 相似文献
142.
The condition of the surfaces is of crucial importance for the deuterium permeation through materials. In this work a study of the surface constants for the adsorption (σk1) and release (σk2) of deuterium under different surface conditions on the martensitic steel DIN 1.4914 (MANET) has been carried out. The growth of an oxide surface layer (Cr2O3) of about 25–30 nm in a MANET sample, heat treated in an oxidizing environment, compared to the bare MANET that have a ‘natural' oxide of about 5 nm has provoked a reduction of both the permeation rate and the recombination coefficient (about 3 orders of magnitude). In addition, the permeation governing process has changed from diffusion-limited to surface-limited. The measurements of the permeation rate of deuterium were performed by a gas-phase permeation technique over the temperature range 574–746 K and for deuterium driving pressures in the range from 3 to 105 Pa. 相似文献
143.
Fischer-Tropsch synthesis on Fe-Mn ultrafine catalysts 总被引:2,自引:0,他引:2
The Fischer-Tropsch (FT) synthesis on Fe-Mn ultrafine catalysts prepared by a special degradation method of Fe-Mn complexes is presented. The effects of preparation method and Mn content on the FT performance are examined and the active phases and the role of Mn are elucidated. 相似文献
144.
In the early eighties, at the Boris Kidrich Institute Vincha, a method for measuring specific heat and electrical resistivity of electrical conductors in the millisecond resolution range was developed for measurements from room temperature to 1900 K. Over a period of nearly 10 years, the method was applied to different materials, including pure metals, ferrous, and nickel/ chromium alloys, and to the characterization of candidate materials for thermophysical property reference standards. This paper describes the method and reviews the results obtained in specific heat and electrical resistivity studies of ferromagnetic and other materials. The paper also demonstrates capabilities of the method for describing phase transitions or anomalies in pure metals (Fe, Co, Ni) or alloys (Nichrome, austenitic stainless steel).Paper presented at the Second Workshop on Subsecond Thermophysics, September 20–21, 1990, Torino, Italy. 相似文献
145.
被Kerr介质包围的J—C模型中光场位相特性 总被引:2,自引:0,他引:2
本文应用Pegg-Barnett位相理论讨论了被Kerr介质包围的J-C模型中光场的位相性质。 相似文献
146.
By DTA and x-ray diffraction the phase relations in the pseudobinary system In-CuInS2 have been investigated. CuInS2 hs a melting point of 1090° C and within this system there is a broad region of liquid immiscibility. A four phase
invariant reaction exists at 633° C which is of the form: L2 = L1+ CuInS2 + InS. 相似文献
147.
148.
149.
Chih-Chun Hsieh Tao-Chih Chang Dong-Yih Lin Ming-Che Chen Weite Wu 《Metals and Materials International》2007,13(5):411-416
The purpose of this study is to investigate the precipitation characteristics of σ phase in the fusion zone of stainless steel
welds at various welding passes during a tungsten are welding (GTAW) process. The morphology, quantity, and chemical composition
of the δ-ferrite and σ phase were analyzed using optical microscopy (OM), a ferritscope (FS), a X-ray diffractometer (XRD),
scanning electron microscopy (SEM), an electron probe micro-analyzer (EPMA), and a wavelength dispersive spectrometer (WDS),
respectively. Massive δ-ferrite was observed in the fusion zone of the first pass welds during welding of dissimilar stainless
steels. The σ phase precipitated at the inner δ-ferrite particles and decreased δ-ferrite content during the third pass welding.
The σ and δ phases can be stabilized by Si element, which promoted the phase transformation of σ→ϱ+λ2 in the fusion zone of the third pass welds. It was found that the σ phase was a Fe−Cr−Si intermetallic compound found in
the fusion zone of the third pass welds during multi-pass welding. 相似文献
150.