材料期刊网

Optimization Study of Calcium Leaching From Steelmaking Slag

XU An-jun , ZHANG Hui-ning , YANG Yi , CUI Jian , HE Dong-feng , TIAN Nai-yuan

钢铁研究学报(英文版)

Abstract： In order to study calcium leaching behavior for the steelmaking slag, factors that influence the leaching yield have been optimized. The results show that granularity of the slag, liquid to solid ratio (in short for L/S), temperature and reaction time have a significant effect on the leaching yield. The optimal conditions for leaching are determined as follows: 1) the granularity at 75 μm, L/S at 100, temperature at 60 ℃; 2) the granularity at 75 μm, L/S at 50, temperature at 40 ℃. Finally, the optimal leaching yield under these conditions is about 15%.

关键词: Key words: steelmaking slag , leaching yield , calcium content

Establishment of Neural Network Prediction Model for Terminative Temperature Based on Grey Theory in Hot Metal Pretreatment

ZHANG Hui-ning , XU An-jun , CUI Jian , HE Dong-feng , TIAN Nai-yuan

钢铁研究学报(英文版)

In order to improve the accuracy of model for terminative temperature in steelmaking, it is necessary to predict and control before decarburization. Thus, an optimization neural network model of terminative temperature in the process of dephosphorization by laying correlative degree weights to all input factors related was used. Then simulation experiment of model newly established is conducted utilizing 210 data from a domestic steel plant. The results show that hit rate arrives at 5645% when error is within plus or minus 5%, and the value is 100% when within ±10%. Comparing to the traditional neural network prediction model, the accuracy almost increases by 6839%.Thus, the simulation prediction fits the real perfectly, which accounts for that neural network model for terminative temperature based on grey theory can reflect accurately the practice in dephosphorization. Naturally, this method is effective and practicable.

关键词: grey theory , correlation degree , dephosphorization , terminative temperature , neural network model

Steel Temperature Compensating Model With Multi-Factor Coupling Based on Ladle Thermal State

WU Peng-fei , XU An-jun , TIAN Nai-yuan , HE Dong-feng

钢铁研究学报(英文版)

Combined with the parameters of the production process of a steel factory, numerical simulations for a new ladle from preheating to turnover are conducted using the finite element analysis system software (ANSYS). The measured data proved that the simulated results are reliable. The effects of preheating time, thermal cycling times, and empty package time on steel temperature are calculated, an ideal preheating time is provided, besides, based on the analysis of a single factor and use the nonlinear analysis method, a steel temperature compensating model with diversified coupling factors is proposed, with the largest error of the present coupling model at 1462 ℃, and the errors between actual and target steel temperature in tundish after the model is applied to practical production are basically controlled within ±6 ℃, which can meet the accuracy of the manufacturer and has a practical guiding significance for the production in steelmaking workshops.

关键词: ladle , thermal state , multiple-factor coupling , numerical simulation , compensation model

THERMAL NUCLEATION AND GROWTH OF He BUBBLES IN He IMPLANTED STAINLESS STEELS

ZHANG Lei WANG Peixuan TAO Rong MA Ruzhang ZHANG Guoguang University of Science and Technology Beijing , Beijing , China professor , Department of Materials Physics.University of Science and Technology Beijing.Beijing 100083 , China

金属学报(英文版)

Nucleation and growth of He bubbles at different annealing temperatures T≤1023 K in stain- less steels HR-2 and SS321,implanted with He~+(40-70 keV.1×10~(16)-6× 10~(17) He~+/cm~2),were ohserved under TEM.T=0.45T_m seems to be a transition temperature.The He bubbles continue mainly their nucleation at 0.3T_m< T<0.45T_m,and grow predominantly at T≥0.45T_m,due probably to migration and coalescence by surface diffusion of metal atoms around the bubbles.The apparent activation energies for the growth are found to he 0.41 and 0.31 eV for HR-2 and SS321 respectively.The bubble density in HR-2 is greater than that in SS321 within whole measuring temperature range,and the onset temperature of rapid swelling is also higher.It is believed that the resistance of HR-2 to He is superior to that fo SS321.

关键词: stainless steel , null , null , null , null

高温退火后含He纳米晶钛膜中He相关缺陷的演化

李悦 , 邓爱红 , 刘莉 , 王康 , 谢莎

材料研究学报

利用x射线衍射(xRD)和慢正电子束分析(SPBA)技术研究高温退火后含He钛膜的微观结构和钛膜内He相关缺陷的演化.XRD分析表明,高温退火后Ti和Si在高温下发生反应形成稳定的多晶TiSi2化合物,He原子的掺入会影响TiSi2晶体的择优取向,而对TiSi2晶粒尺寸的影响较小.SPBA结果表明,室温下,钛膜内的缺陷浓度或尺寸会随着掺He浓度的增加而增大;高温退火后,当He浓度小于5％(原子分数,下同)时(除2％外),钛膜内的He相关缺陷浓度随着He浓度增加相应地增加.当He浓度增加到14％时,高温会使较高浓度的He原子、He-空位复合体以及小He泡迁移聚集形成一些尺寸较大He泡,而较大He泡周围与He相关的小尺寸缺陷的浓度则会发生相应地减少.

关键词: 金属材料 , 含He钛膜 , 直流磁控溅射 , He相关缺陷 , XRD , SPBA

直流磁控溅射沉积含He钛膜的研究

施立群 , 金钦华 , 刘超卓 , 徐世林 , 周筑颖

原子核物理评论 doi:10.3969/j.issn.1007-4627.2005.01.045

研究了用He/Ar混合溅射气体的直流磁控溅射制备钛膜中He的掺入现象.分析结果表明,大量的He原子(He/Ti原子比高达56%) 被均匀地引入到Ti膜中,He含量可由混合溅射气体的He分量精确控制.通过调节溅射参数,可实现样品中He的低损伤引入.研究还发现,溅射沉积的含氦Ti膜具有较高的He成泡剂量和高的固He能力,这可能是溅射沉积形成了纳米晶Ti膜所致.纳米晶Ti膜较粗晶材料具有很高浓度的He捕陷中心,使He泡密度增大而泡尺寸减小.随He引入量的增加,Ti膜的晶粒尺寸减小,He引起的晶体点阵参数和X射线衍射峰宽度增大,晶体的无序程度增加.

关键词: 氦 , 损伤 , 泡 , 钛膜 , 溅射沉积

Heuristic treatments of tricritical behaviour as observed in 4He-3He mixtures and in polymeric assemblies

Physics and Chemistry of Liquids

Tricritical behaviour in three dimensions is accessible to experiment in, for example, 4He-3He mixtures and some polymeric assemblies. Here, by largely heuristic arguments, which appeal however to some specific model Hamiltonians, we indicate how one can understand the gist of the experimental results near the tricritical point in the systems cited above. We point out that the spin fluctuations at the tricritical point are much weaker than those at the critical point, which leads to the conclusion that the tricritical behaviours can be described well by the mean-field exponents with logarithmic corrections, at d = 3.

关键词: tricritical behaviour;tricritical exponents;4He-3He mixtures;polymeric assemblies;Ising model;emery-griffiths model;single-ion-anisotropy;ising-model;phase-separation;magnetic-properties;lattice statistics;crystal-field;exponents;superconductivity;transition

低能He2+与He原子碰撞转移电离出射电子能谱研究

冯文天 , 马新文 , 朱小龙 , 张少峰 , 刘惠萍 , 李斌 , 闫顺成

原子核物理评论

利用反应显微成像谱仪对70和100 keV He2+与He原子碰撞转移电离(TI)过程中不同出射角度的电子能谱进行了测量,观测到出射电子能谱具有如下分布特征:出射电子速度分布介于0和入射离子速度νp之间;在不同出射角度电子能谱分布均有一极大值存在,随着出射角度的增大,能谱分布极大值逐渐减小; 当电子出射角度等于45°时,多数电子集中在0 eV附近.上述特征可由低能离子-原子碰撞"准分子"模型进行定性解释.在100 keV He2+-He转移电离出射电子能谱中有靶电子被俘获至散射离子连续态(electron capture to continuum,简称ECC)电子的贡献,这可看做是动力学两步过程的作用.

关键词: 反应显微谱仪 , 转移电离 , ECC电子 , "准分子"模型

非束缚核9He的实验研究

王宏伟

原子核物理评论 doi:10.3969/j.issn.1007-4627.2004.03.003

简要介绍了目前有关非稳定核9He的实验和理论研究现状.现代壳模型理论计算表明 9He的基态自旋宇称为1/2+, 而不是1/2-, 即存在自旋宇称翻转现象.到目前为止, 实验上虽然观测到了9He的几个共振态, 但还不能确认其基态的能量和自旋宇称值.利用新的实验技术--逆运动学弹性共振散射, 对9He核进行研究, 给出了共振态的自旋宇称可能的取值范围.在ISOL型次级束装置上的实验有望能给出9He核能级的精确测量.

关键词: 放射性束流 , 非束缚核 , 核结构

He注入单晶Si表面形貌的变化研究

李炳生 , 张崇宏 , 杨义涛 , 周丽宏

原子核物理评论

沿Si的(100)面注入He离子, 能量为30 keV、剂量为5×1016 ions/cm2. 注入后样品切成几块, 在真空炉中分别做退火处理, 退火温度从600 ℃到1 000 ℃, 退火时间均为30 min. 利用原子力显微镜研究了各个样品表面形貌的演化. 发现样品表面形貌与退火温度相关联. 假设在气泡中He原子与空位的比值很高, 导致样品内部存在高压的He泡, 从而使样品表面形貌发生变化. 探讨了在Si中He泡随退火温度的演化和He原子在材料中的释放机制及其对表面的影响.

关键词: 单晶Si , 离子注入 , He泡 , 原子力显微镜 , 表面形貌