材料期刊网

Microstructure and Properties of Mo Microalloyed Cold Rolled DP1000 Steels

HAN Qihang , KANG Yonglin , ZHAO Xianmeng , L Chao , GAO Lufeng

钢铁研究学报(英文版)

Two kinds of ultrahigh strength cold rolled dual phase steels have been developed by designing CSiMnCr and CSiMnCrMo alloy systems. Tensile strength and elongation of both steels exceed 1100 MPa and 10%, respectively. The microstructures of both steels consist of massive martensite and ferrite. And the massive martensite of Mofree steel disperses in the ferrite with volume fraction of 64%. However, the massive martensite of Mocontaining steel is connected or closed by small martensite islands each other, and martensite volume fraction is 69%. As to Mofree steel, the yield strength, yield ratio, and work hardening exponent n are 548 MPa, 049, and 026, respectively. As for Mocontaining one, the yield strength, yield ratio, and n value are 746 MPa, 066, and 033, respectively. Besides, the ferrite of Mofree steel is deformed at the initial stage of plastic deformation. However, for Mocontaining one, Mo solution strengthened ferrite and small overaged martensite islands are deformed preferentially at small strain, which causes the yield strength to reach approximately 200 MPa higher than that of Mofree steel.

关键词: Mo , dual phase steel , microstructure , property , deformation mechanism

Crystal structure and photoluminescence of Tb3+ doped Y3GaO6

Journal of Alloys and Compounds

A solid solution with formula (Y1-xTbx)(3)GaO6 (x = 0-0.5) was prepared by solid-state reaction method. Powder X-ray diffraction (XRD) shows that Y3GaO6 is isostructural to Gd3GaO6 (Cmc2(1)), and the lattice parameters are a = 8.8364(1) angstrom, b = 11.0899(1) angstrom and c = 5.3937(1) angstrom. Atomic parameters were derived by Rietveld refinement of the XRD pattern. Photoluminescence (PL) spectra show a strong green emission of 543 nm from the D-5(4) -> F-7(5) transition of Th3+ at room and liquid nitrogen temperature. There is a wide saturation range of the PL intensity for the Th3+ content from x = 0.04-0.20, and a long life time about 1200 mu s for the green 543 nm emission at room temperature. (c) 2006 Elsevier B.V. All rights reserved.

关键词: Y3GaO6;crystal structure;Tb3+ doped;photoluminescence;luminescence properties;dependence;y3al5o12;phosphor;ions;ce3+;tb-3;uv

A systematic study on crystal structure and magnetic properties of Ln(3)GaO(6) (Ln = Nd, Sm, Eu, Gd, Tb, Dy, Ho and Er)

Journal of Solid State Chemistry

The crystal structures of a series of compounds with the composition Ln(3)GaO(6)(Ln = Nd, Sm, Eu, Gd, Tb, Dy, Ho and Er) synthesized by solid-state reaction at 1400degreesC are investigated. X-ray diffraction shows that Ln3GaO6 has a non-centro symmetric orthorhombic structure (space group Cmc2(1)). Lattice parameters a, b, c and cell volume and the average distances between Ln(l)-O, Ln(2)-O of these compounds decrease with the decreasing of the radii of trivalent Ln ions, which accord with the expected lanthanide contraction behavior. There are two sites of seven-fold coordination for Ln atoms with oxygens, and Ga atoms are in oxygen tetrahedra which are distorted and elongated along the a-axis. Magnetization measurements indicate that the susceptibility X changes with temperature in Curie-type manner. (C) 2004 Elsevier Inc. All rights reserved.

关键词: Ln(3)GaO(6);crystal structure;Rietveld refinement;X-ray diffraction;garnets

Optical spectra of Ln(3+)(Nd3+, Sm3+, Dy3+, Ho3+, Er3+)-doped Y3GaO6

Journal of Luminescence

Ln(3+) (Ln = Nd, Sm, Eu, Gd, Dy, Ho, Er)-doped Y3GaO6 compounds were prepared by solid-state reaction, and their optical spectra such as absorption, photoluminescence, excitation and time-resolved spectra have been measured for Ln Nd, Sm, Dy, Ho, Er. X-ray powder diffraction shows that the lattice parameters of the compounds (Y(0.96)Ln(0.04))(3)GaO6 decrease with the decrease of the radii of trivalent Ln(3+) ions, indicating that Ln(3+) ions have substituted for y(3+) ions in the lattice. Optical spectra show that there are obvious absorptions at ultraviolet to visible region. The strong emissions in visible and infra-red region show that Y3GaO6 is a suitable host for rare-earth-doped laser crystal and phosphor materials. (C) 2004 Elsevier B.V. All rights reserved.

关键词: crystal-field;absorption-spectra;luminescence;y3ga5o12;glasses;garnet;y2o3;ions;laf3;tb3

Optical properties of (Y1-xTmx)(3)GaO6 and subsolidus phase relation of Y2O3-Ga2O3-Tm2O3

Journal of Solid State Chemistry

A serial of samples in Y2O3-Ga2O3-Tm2O3 pseudo-ternary system are prepared by solid-state chemical reaction method. The range of solid solution in (Y1-xTmx)(3)GaO6 is 0 < x < 0.384. Powder X-ray diffraction shows that the compounds crystallize in Gd3GaO6 (Cmc2(1))-type structure. The solid solubilities of Y3+xGa5-xO12 (x = 0-0.77) and Tm3+xGa5-xO12 (x = 0-0.62) are 37.5-47.11 at% Y2O3, and 37.5-45.26 at% Tm2O3, respectively. PL spectra of Tm-doped Y3GaO6 show that there is a sharp blue emission at similar to 456 nm from the D-1(2) -> F-3(4) transition at room temperatures with two lifetimes (similar to 5 and similar to 15 mu s) and a narrow saturation range of PL intensity for the Tm3+ content from x = 0.005 to 0.03. The sharp emission and long lifetime of (Y1-xTmx)(3)GaO6 indicate that Y3GaO6 is a potential phosphor and laser crystal host material. (c) 2005 Elsevier Inc. All rights reserved.

关键词: Tm3+ -doped Y3GaO6;Y2O3-Ga2O3-Tm2O3 system;(Y1-xTmx)(3)Ga5O12 solid;solution;luminescence;crystal-structure;luminescence;phosphor;cations;ions;tb3

不同温度下碳源对AOA-SBR工艺PAO与GAO竞争释磷的影响

张兰河 , 李德生 , 王旭明 , 张海丰

硅酸盐通报

为了提高生物除磷效率,研究采用AOA-SBR工艺进行了长期连续除磷实验,考察不同温度下碳源(乙酸钠、丙酸钠、葡萄糖)对PAO与GAO竞争的影响.结果表明:当温度由10℃升高至25℃时,利用丙酸钠作为碳源时,污泥含磷量与含糖量分别从7.2％和5.1％升高至7.9％和6.3％,PHA转化量升高了23.1 mg/L,厌氧释磷量从105.9 mg/L升高至149.9 mg/L,VSS/MLSS由71％降低至65％;利用乙酸钠作为碳源时,污泥含磷量与含糖量分别从6.9％和5.3％升高至7.6％和6.7％,PHA转化量升高了23.9 mg/L,厌氧释磷量从73.8 mg/L升高至108.8 mg/L,VSS/MLSS由73％降低至71％;利用葡萄糖作为碳源时,污泥含磷量与含糖量分别从5.8％和6.3％升高至6.6％和8.8％,PHA转化量升高了33.2 mg/L,厌氧释磷量从37.4 mg/L升高至43.2 mg/L,VSS/MLSS由80％升高至88％.当温度升高至30℃时,3个反应器均出现厌氧末期PHA浓度下降和糖原浓度升高,厌氧释磷量减少,污泥含磷量均下降,污泥含糖量上升,VSS/MLSS均很高.与葡萄糖相比,采用乙酸钠和丙酸钠作为碳源,有利于PAO生长繁殖,PAO为优势菌种,抑制GAO增殖.同时,低温更有利于PAO的生长繁殖.

关键词: 温度 , 碳源 , SBR , PAO与GAO

Lu-Si-O体系在高温水蒸气环境中的腐蚀行为

洪智亮 , 成来飞 , 鲁琳静 , 张立同 , 王一光

无机材料学报 doi:10.3724/SP.J.1077.2010.00186

采用溶胶-凝胶法制得三种镥硅酸盐体系粉体材料. 以氧化物的摩尔比来表示此三种粉体, 分别为：Lu₂O₃·SiO₂、Lu₂O₃·2SiO₂和Lu₂O₃·2.26SiO₂. 在1400℃、50%H₂O-50%O₂静态常压气氛下, 研究了它们的耐水蒸气腐蚀性能.以单位面积重量变化率表征材料的耐水蒸气腐蚀性能, 结合X射线衍射（XRD）、傅里叶红外光谱（FTIR）和扫描电镜能谱分析（SEMEDS）等分析手段, 揭示了镥硅酸盐体系在高温水蒸气环境中的腐蚀机制和反应机理. 结果表明：三种原始粉体主要物相依次为：Lu₂SiO₅+Lu₂Si₂O₇、 Lu₂Si₂O₇+SiO₂和Lu₂Si₂O₇+SiO₂. 在水蒸气作用下, Lu₂SiO₅相与Al₂O₃反应生成新相Lu₃Al₅O₁₂, 而Lu₂Si₂O₇相并未受到水蒸气的作用而发生任何反应, 表现出优异的化学稳定性.

关键词: Lu₂SiO₅ , Lu₂Si₂O₇ , environmental barrier coating (EBC) , water vapor corrosion

Lu-Si-O体系在高温水蒸气环境中的腐蚀行为

洪智亮 , 成来飞 , 鲁琳静 , 张立同 , 王一光

无机材料学报 doi:10.3724/SP.J.1077.2010.00186

采用溶胶-凝胶法制得三种镥硅酸盐体系粉体材料.以氧化物的摩尔比来表示此三种粉体,分别为:Lu_2O_3·SiO_2、Lu_2O_3·2SiO_2和Lu_2O_3·2.26SiO_2.在1400℃、50%H_2O-50%O_2静态常压气氛下,研究了它们的耐水蒸气腐蚀性能.以单位面积重量变化率表征材料的耐水蒸气腐蚀性能,结合X射线衍射(XRD)、傅里叶红外光谱(FTIR)和扫描电镜能谱分析(SEM-EDS)等分析手段,揭示了镥硅酸盐体系在高温水蒸气环境中的腐蚀机制和反应机理.结果表明:三种原始粉体主要物相依次为:Lu_2SiO_5+Lu_2Si_2O_7、Lu_2Si_2O_7+SiO_2和Lu_2Si_2o_7+SiO_2.在水蒸气作用下,Lu_2SiO_5相与Al_2O_3反应生成新相Lu_3Al_5O_(12)而Lu_2Si_2O_7相并未受到水蒸气的作用而发生任何反应,表现出优异的化学稳定性.

关键词: Lu_2SiO_5 , Lu_2Si_2O_7 , 环境障碍涂层 , 水蒸气腐蚀

Lu2O3和Lu2O3∶Eu3+单分散球形粉体合成及其荧光性能研究

马畅 , 李晓东 , 董宇 , 刘绍宏 , 朱琦 , 李继光 , 霍地 , 孙旭东

中国稀土学报 doi:10.11785/S1000-4343.20130411

以Lu(NO3)3和尿素为原料,采用均相沉淀法合成镥盐前驱体,研究Lu3+浓度、尿素/Lu3+摩尔比R对前驱体形貌的影响.结果表明,在反应温度为95℃时,低Lu3+浓度有利于单分散球形粉体的合成,并且适当的调整R值可将单分散球形颗粒尺寸控制在180 ～ 270 nm之间.在此基础之上,研究Eu3+掺杂Lu2O3单分散球形荧光粉体的合成,探讨了Eu3+的掺杂量(1％,3％,5％,7％,9％(原子分数))及煅烧温度(600～ 1200℃)对颗粒形貌及其荧光性能的影响.结果表明,Eu3+的掺杂使所得(Lu,Eu)盐前驱体颗粒尺寸远小于单纯的Lu盐前驱体,且Eu含量对荧光粉的荧光强度有着显著的影响,荧光淬灭浓度为5％.在考察的煅烧温度范围内,荧光粉的荧光强度随煅烧温度的提升而增强.

关键词: Lu2O3 , Eu3+ , 均相沉淀 , 单分散球形 , 前驱体 , 荧光性能 , 稀土

TEMPERATURE-DEPENDENCE OF THE MAGNETIC-PROPERTIES OF THE RARE-EARTH TRANSITION-METAL INTERMETALLIC LU2FE14C

Journal of Magnetism and Magnetic Materials

Magnetization curves of the ternary tetragonal compound Lu2Fe14C were measured in an extracting-sample magnetometer in the temperature range from 1.5 to 300 K. The temperature dependence of the magnetic properties of Lu2Fe14C is discussed.

关键词: anisotropy