Journal of Materials Research
Deformation-induced gamma -> DI-alpha(2) phase transformation was verified to occur in the twin-intersection region of a Ti-45Al-8Nb (at.%) alloy compressed at room temperature. High-resolution image observations of the deformation-induced DI-alpha(2) phase suggested that the orientation relationship between the DI-alpha(2) and gamma phases remained the typical one: (0001)(DI-alpha 2)//{111}(gamma), [11 (2) over bar0](DI-alpha 2)//< 101]gamma. The conversion of stacking sequence from ordered face-centered tetragonal to ordered nonequilibrium hexagonal close-packed structure was accomplished by the movement of a/6 < 11 (2) over bar] Shockley partial dislocations on every other {111}(gamma) plane. Compositional analysis based on energy dispersive spectra revealed that the DI-alpha(2) phase had the same composition as the matrix gamma phase. No compositional diffusion Occurred because the plastic deformation was carried out at room temperature. The strong stress concentration in the intersection region was the major force to induce the gamma -> DI-alpha(2) phase transformation in the process of room-temperature compression.
关键词:
titanium aluminides;mechanical-properties;room-temperature;microstructure;intermetallics;microscopy;nb
徐江华
,
李山青
上海金属
DI材是宝钢的重要产品,主要用于碳酸饮料罐和啤酒罐.DI材沿宽度方向的厚度均匀性要求十分严格.为了减少DI材的横向厚差,开发了横向厚差自动控制系统并应用在某冷连轧机上.该控制系统使用了基于鲁棒性能指标(robustness specification)的横向厚差自动控制算法,从而使厚度0.229 mm以下的DI材的横向厚差被控制在±4μm以内.
关键词:
DI材
,
冷轧
,
横向厚差
,
自动控制
Hu Wang Juan Xie Kangping Yan Ming Duan
材料科学技术(英文)
Different morphologies of zinc oxide (ZnO), including microrods, hexagonal pyramid-like rods and flower-like rod aggregates, had been synthesized, respectively, on glass substrates by controlling the reaction conditions (such as precursor concentration, reaction time and pH value) of hydrothermal method. The morphologies of the as-obtained ZnO were observed with scanning electron microscopy and transmission electron microscopy.
Also, the crystalline natures of di®erent ZnO crystals were analyzed with X-ray diffraction. The possible growth mechanism of ZnO crystals with di®erent morphologies was discussed.
关键词:
Zinc oxide
Y.B. Hou
金属学报(英文版)
In this paper, the PMMA films doped with N,N'-diphenyl-N,N'-di(m-tolyl)-benzidineand rubrene were fabricated by spin coating, and the effect of photooxidation onthe photoluminescence of the doped PMMA thin films was investigated. The resultsshowed that under the irradiation of 350nm UV light, N,N'-diphenyl-N,N'-di(m-tolyl)-benzidine can sensitized rubrene and results in the enhancement in the photooxrationof rubrene. The effect of photooxidation on the photoluminescence from rubrene w asmore obvious. Both lifetime measurement and in situ measurement of photolumines-cence showed that rubrene molecules exist in two chemical surroundings.
关键词:
photoluminescence
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