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1.
A new model, based on Seetharaman’s viscosity model and Chou’s geometric-thermodynamic model, to predict the viscosity of
ternary-metallic melts has been established. The viscosities of Ag-Au-Cu and Ag-Sn-Cu systems have been calculated with the
present model, and the results are consistent with the experimental data. The viscosities of Au-Ni-Cu, Fe-Ni-Cu, Al-Sn-Cu,
and In-Sn-Bi systems have also been predicted by the present model. 相似文献
2.
3.
采用渗流铸造工艺制备了钨丝增强不同Nb含量的Zr基金属玻璃复合材料,利用X-Ray衍射、扫描电镜以及电子探针考察了复合材料界面反应和界面扩散情况,研究了基体合金中的Nb含量对复合材料界面反应和界面扩散的影响。结果表明:对Zr55Al10Ni5Cu30基复合材料,渗流时,钨丝与液相中的Zr发生界面包晶反应,生成W5Zr3界面相,并使界面位置向液相方向移动。在Zr55Al10Ni5Cu30合金的基础上添加Nb,发现Nb优先在钨丝界面偏聚,降低了Zr在钨丝界面的偏聚和活度,抑制钨丝与液相中的Zr包晶反应的发生,没有生成W5Zr3界面相,界面处只存在简单的扩散层。同时发现Zr元素在钨丝中的扩散系数降低,此时界面位置向钨丝方向移动。 相似文献
4.
A geometric model for calcuating the visocsity of multi-component melt from related binary physicochemistry properties was derived based on Chou‘s thermodynamic geometric model.The model derved was employed to predict the viscosity of Au-Ag-Cu alloys.The results show that the calculated viscosity for Au-Ag-Cu alloys meet the experimental data very well.In addition,the viscosity of Bi-Sn-In systems was also predicted with this model. 相似文献
5.
金属快速凝固的非平衡超急速传热模型 总被引:2,自引:0,他引:2
运用非Fourier传热理论建立了金属快速凝固过程中的非平衡传热理论模型,包括非Fourier方程的建立、传热与相变模拟,模拟计算表明:(1)在溅射激冷条件下,界面换热系数越大,界面冷却速度和移动速度也越高。在界面换热系数相同时,计算得到的界面冷却速度随着固-液界面高度的提高呈现先上升而后下降的变化趋势;计算得到的冷却速度值明显小于Fourier定律的计算值。(2)在激光加热条件下,计算的界面移动速度在凝固开始时先急剧增加,然后渐趋平稳,计算还表明,金属的过热及过冷度与其热物性相关。 相似文献
6.
LIU Yan HUI Xidong and WANG Huanrong) Department of Materials Science Engineering Shandong Institute of Architecture Engineering Jinan China) State Key Laboratory for Advanced Metals Materials University of Science Technology Beijing Beijing China) Key Laboratory of Liquid Structure Heredity of Materials Ministry of Education Shandong University Jinan China 《稀有金属(英文版)》2003,22(4)
The influence of pre-annealing on thermal stability of the amorphous Zr70Cu20Ni10 alloy was reported by em-ploying the differential scanning calorimetry (DSC) and high-resolution transmission electron microscopy (HRTEM) tech-niques. It has been observed that the supercooled liquid region decreases with increasing the annealing time under isothe-mal conditions, indicating that the thermal stability of the amorphous Zr70Cu20Ni10 alloy decreases gradually. HRTEM ob-servations reveal that there exist some ordered atomic clusters in the amorphous matrix at the relaxation stage. These or-dered atomic clusters can be regarded as precursors for the precipitation of the crystalline phases in the subsequent crystal-lization process. The reasons resulting in the decrease in thermal stability of the amorphous Zr70Cu20Ni10 alloy with anneal-ing time are discussed through the Gaussian decomposition for the radial distribution function of the amorphous Zr70Cu20Ni10 alloy. 相似文献
7.
8.
使用Fenton试剂对铁锰矿井水进行处理试验,论述了反应温度、H2O2的投加量、pH、反应时间对Fenton试剂处理矿井水的影响,讨论了Fenton试剂处理酸性矿井废水的机理。结果表明:芬顿试剂对铁锰矿井水中锰的去除效率很高,矿井水中的Fe2+能与H2O2形成Fenton试剂后产生的具有强氧化性的.OH能有效处理矿井水中的Mn2+。对于原水Mn2+的初始浓度为2 mg/L,Fe2+的初始浓度为250 mg/L,pH为5,当控制反应温度为25℃,H2O2的投加量为8 mmol/L,调节pH值为4.5,反应时间为10 m in,Mn2+去除效率可以达到78.1%以上。 相似文献
9.
Ultra-Stable and Sensitive Ultraviolet Photodetectors Based on Monocrystalline Perovskite Thin Films
Xu Li Chang Liu Feng Ding Zheyi Lu Peng Gao Ziwei Huang Weiqi Dang Liqiang Zhang Xiaohui Lin Shuimei Ding Bailing Li Ying Huangfu Xiaohua Shen Bo Li Xuming Zou Yuan Liu Lei Liao Yiliu Wang Xidong Duan 《Advanced functional materials》2023,33(15):2213360
The detection of ultraviolet (UV) radiation with effective performance and robust stability is essential to practical applications. Metal halide single-crystal perovskites (ABX3) are promising next-generation materials for UV detection. The device performance of all-inorganic CsPbCl3 photodetectors (PDs) is still limited by inner imperfection of crystals grown in solution. Here wafer-scale single-crystal CsPbCl3 thin films are successfully grown by vapor-phase epitaxy method, and the as-constructed PDs under UV light illumination exhibit an ultralow dark current of 7.18 pA, ultrahigh ON/OFF ratio of ≈5.22 × 105, competitive responsivity of 32.8 A W−1, external quantum efficiency of 10867% and specific detectivity of 4.22 × 1012 Jones. More importantly, they feature superb long-term stability toward moisture and oxygen within twenty-one months, good temperature tolerances at low and high temperatures. The ability of the photodetector arrays for excellent UV light imaging is further demonstrated. 相似文献
10.
Xiaohui Lin Long Chen Chenglin He Yiliu Wang Xu Li Weiqi Dang Kun He Ying Huangfu Dan Wu Bei Zhao Bo Li Jia Li Xidong Duan 《Advanced functional materials》2023,33(1):2210278
Single crystal metal halide perovskites thin films are considered to be a promising optical, optoelectronic materials with extraordinary performance due to their low defect densities. However, it is still difficult to achieve large-scale perovskite single-crystal thin films (SCTFs) with tunable bandgap by vapor-phase deposition method. Herein, the synthesis of CsPbCl3(1–x)Br3x SCTFs with centimeter size (1 cm × 1 cm) via vapor-phase deposition is reported. The Br composition of CsPbCl3(1–x)Br3x SCTFs can be gradually tuned from x = 0 to x = 1, leading the corresponding bandgap to change from 2.29 to 2.91 eV. Additionally, an low-threshold (≈23.9 µJ cm−2) amplified spontaneous emission is achieved based on CsPbCl3(1–x)Br3x SCTFs at room temperature, and the wavelength is tuned from 432 to 547 nm by varying the Cl/Br ratio. Importantly, the high-quality CsPbCl3(1–x)Br3x SCTFs are ideal optical gain medium with high gain up to 1369.8 ± 101.2 cm−1. This study not only provides a versatile method to fabricate high quality CsPbCl3(1–x)Br3x SCTFs with different Cl/Br ratio, but also paves the way for further research of color-tunable perovskite lasing. 相似文献