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[en] The geometrical structures and electronic properties of six fullerene isomers of C100 were studied at the HF/6-31G* and B3LYP/6-31G* levels, respectively. The results of the fully optimized calculations show that three C100 isomers 449:D2, 425:C1 and 442:C2 are near isoenergetic isomers. The energies and properties of C100 hexaanions were calculated. The C1006- (450:D5) isomer is predicted to be the most stable isomer at the B3LYP/6-31G* level, and the C1006- (449:D2) isomer is 44.1 kcal/mol higher in energy. The heterofullerenes C96X4 (X=N, P, B, Si) formed from the initial C100 (449:D2) have also been investigated at the B3LYP/6-31G* level. The HOMO-LUMO gaps and aromaticities show that the replacement of fullerene carbon atoms with four heteroatoms can enhance the electronic stabilization of C100 (449:D2).
[en] The present report summarizes and discusses the recent results on developing a modern, nuclear grade FeCrAl alloy designed to have enhanced radiation tolerance and weldability. The alloys used for these investigations are modern FeCrAl alloys based on a Fe-13Cr-5Al-2Mo-0.2Si-0.05Y alloy (in wt.%, designated C35M). Development efforts have focused on assessing the influence of chemistry and microstructure on the fabricability and performance of these newly developed alloys. Specific focus was made to assess the weldability, thermal stability, and radiation tolerance.
[en] The aging alloy of AIMgSil containing Mg2Si of 1.29 % has been done with the following steps: e.q (a) part of the specimen was heated at 400oC during 3 hours, and (b) the other part was done with solution treatment at 550oC followed by quenching. After quenching a part of the specimen was aged at room temperature and other specimen was aged at 160oC during 16 hours. After the specimen had been heated, then it was shaped into thin foil to be examined by Transmission Electron Microscope. The result showed that the heating at temperature of 400oC during 3 hours created a second phase (i.e.Mg2Si) was like stick shape with the hexagonal structure at  orientation and matrix , and the hardness was 31 HB. The aging of specimen at room temperature gave result a GP zone which was like the needles shape in the dislocation area of the face center cubic structure at  orientation and  matrix. The hardness obtained was 64 HB. In the other hand the aging process at temperature of 160oC within 16 hours have resulted the precipitate which was greater than that of the former needle shaped as the face center cubic structure without dislocation at matrix with  orientation and  matrix. The hardness at this condition was 94 HB
[en] The amorphous alloys of the Fe81.4-Cr4.0-Mo6.0-Ni5.2C1.0-Mn2.1-Al0.3, Fe71.7-Ni6.0-Co2.4-Cr7.5-Mo7.9-B4.0Si0.5, Fe86-P9.8C1.0-Si0.9-Al1.7-B0.6 systems obtained through the method of the melt fast quenching on the copper disk external side, are studied. The thickness of bands was varied in the limits of 50-80 μm. The cooling rate of bands was constituted 8 x 105 deg C/s. The plastic deformation of the obtained alloys was accomplished through the procedure of the local deformation of amorphous alloy surface by the Vickers diamond pyramid. Thereafter the indenter deformation picture was investigated by the optical and electron microscopes. The anisotropy of the iron base amorphous alloys plastic deformation was revealed. This event is explained on the basis of the notions on the internal strains in the isotropic amorphous bands
[ru]Исследовались аморфные сплавы систем Fe81.4-Cr4.0-Mo6.0-Ni5.2C1.0-Mn2.1-Al0.3, Fe71.7-Ni6.0-Co2.4-Cr7.5-Mo7.9-B4.0Si0.5, Fe86-P9.8C1.0-Si0.9-Al1.7-B0.6 (в вес. %), которые получались методом быстрой закалки расплава на наружную сторону медного диска. Толщина лент варьировалась в пределах 50-80 мкм. Скорость охлаждения лент составляла 8 x 105 град С/с. Пластическая деформация полученных сплавов проводилась с помощью методики локального деформирования поверхности аморфного сплава алмазной пирамидой Виккерса. Далее с помощью оптического и электронного микроскопов изучалась деформационная картина у индентора. Выявлена анизотропия пластической деформации аморфных сплавов на основе железа. Объяснение данному явлению дано на основании представлений о внутренних напряжениях в аморфных лентах
[en] We have used Moessbauer spectroscopy to study the influence of Si addition to Fe60Al40 composition without changing the iron content of the alloy. The study has been performed in ordered and mechanically deformed samples. This work shows that the B2 structure present in ordered Fe60Al40 alloy does not change with Si introduction in the studied ternary alloys. However, the binary Fe60Si40 alloy shows D03 and B20 structures. Mechanical deformation of the ordered samples induces a clear change of the Moessbauer spectra of binary alloys with the presence of new sextets or variation of the previous ones; however, the Moessbauer spectra of the studied ternary alloys are very similar to the ordered ones.
[en] Improvement of composition and several technological parameters of the process of manufacturing alloys of tungsten and aluminium - potassium - silicon (APS) additive are described; these alloys are low-alloyed with rhenium. Tungsten powder with APS - additive was chosen as an initial material for preparing tungsten - rhenium charge. The additive components in the tungsten powder interacted quite actively with tungsten. It is shown that rhenium effect on the tungsten properties in low-alloyed alloys is considerably manifested practically at its low contents. Tungsten alloys with aluminium-potassium-silicon additive containing 3 and 5 % rhenium are produced on the basis of optimized technology in the form of wire from 1-2 mm up to 13-70 μm
[ru]Описаны усовершенствование состава и несколько технологических параметров процесса производства сплавов вольфрама и алюмокалиево-кремниевой присадки (AKS); эти сплавы малолегированны рением. В качестве исходного материала для приготовления вольфрам-рениевой шихты был выбран вольфрамовый порошок с AKS-присадкой. В данном порошке компоненты присадки уже достаточно активно провзаимодействовали с вольфрамом. Показано, что влияние рения на свойства вольфрама в низколегированных сплавах проявляется, и значимо, практически уже при небольших его содержаниях. Сплавы вольфрама с алюмокалиево-кремниевой присадкой, содержащие 3 и 5 % рения, изготавливаются по оптимизированной технологии в виде проволоки от 1-2 мм до 13-70 мкм