压缩弧光等离子束熔覆层中晶相与非晶相

用压缩弧光等离子束在 45钢表面熔覆Fe Cr Si B粉末涂层 ,采用能谱、透射电镜、电子探针对熔覆层结构进行分析。结果表明 ,熔覆层中晶相与非晶相并存 ,晶相由A(Me)、F(Me)、Me2 3 C6 等相组成 ,且 [2 11]A∥ [2 11]Me2 3 C6 ,(111) A ∥ (111) Me2 3 C6 ,(0 11) A ∥ (0 11) Me2 3 C6 ,即A与Me2 3 C6 保持共格关系 ,而[111]F∥ [32 1]Me2 3 C6 ,(10 1) F∥ (111) Me2 3 C6 。非晶相中Si、Cr等元素含量较高 ,从动力学和热力学两方面对非晶的形成进行了分析     

基于交通信息和配电网全成本电价的电动汽车充电负荷调度方法

电动汽车的集中充电行为会在一定程度造成交通拥堵,为解决这一问题,综合考虑交通信息和电网信息,基于边际定价理论得到配电网节点边际电价和交通阻塞成本,构建电动汽车充电的全成本电价模型。在此基础上,提出一种考虑交通信息和配电网全成本电价的电动汽车充电负荷调度方法。通过仿真算例验证,该方法在满足电动汽车充电需求的同时可以有效缓解交通拥堵。     

证券市场中庄家与散户间的确定性微分博弈

基于确定性微分博弈理论,建立了一种庄家与散户间的连续时间的博弈模型.首先将所有散户作为一个整体与庄家进行博弈,以博弈双方持股率的动态关系作为动态系统方程,并以此构建了一个确定性微分博弈模型; 然后运用开环纳什均衡和反馈纳什均衡分别求解出满足共态函数的常微分方程组和满足价值函数的Issacs - Bellman偏微分方程,以此得到庄家与散户博弈的开环纳什均衡策略和反馈纳什均衡策略.该结果可为金融监管部门监管证券市场和证券市场投资者买卖股票提供参考.     

MICROSTRUCTURE STUDY OF CONSTITUENT PHASES IN 2024 SERIES Al ALLOYS

X-ray microanalysis,convergent beam electron diffraction(CBD)and selected area electrondiffraction(SAD)studies on the structures and compositions of the constituent phases in2024 series Al alloys have been conducted.Partial substitution of alloying elements is found tooccur in all the constituent phases,which cause small deviations from the stoichiometric com-positions reported in these ternary compounds.The dominant phase is α-Al_(12)(FeMn)_3Si whichhas a body center cubic crystal structure with the Im■ space group and a=1.25 nm.The nextdominant phase is Cu_2FeAl_7 which has a primitive tetragonal crystal structure with theP4/mnc space group and a=0.6336 nm,c=1.487 nm.The minor phase is α'-Al_(12)Fe_3Si hav-ing α primitive cubic crystal structure with the Pm■ space group and α=1.27 nm.     

关于钛合金热处理和析出相的讨论

通过对钛合金、铝合金和钢的热处理对比分析，从机理上将金属热处理分为三类热处理，将钛合金的热处理归为第三类热处理。对钛合金在热处理过程中出现的主要过渡相进行了介绍，重点分析了α′相、α″相的关系和淬火时效β相，指出α′相和α″相的性质受结构和固溶度的综合影响，β相可更细致地分为β0、β、β′和β″。最后对钛合金中出现的所有相的硬度进行了排序，排序结果为：ω〉α′≈β″〉α″≈α〉β〉β′〉β0。     

EQUILIBRIA OF SYSTEM MoO_3-MoO_2-H_2O-H_2 AND PHASE DIAGRAM FOR SYSTEM Mo-O BETWEEN 400 AND 700℃

使用自行设计的受控气氛热重装置研究了MoO_3—MoO_2-H_2O—H_2系平衡.在P_(H_2O)/P_(H_2)从0.412至0.609,温度从400至534℃范围内直接测定了反应:MoO_3+H_2=MoO_2+H_2O(g)的平衡常数与温度间的关系为1gK_p=0.702-739.8/T获得298.15K下MoO_3标准生成焓及绝对熵分别为:-845.75kJmole~(-1)及78.1 J·K~(-1)mole~(-1) 实验表明,存在于MoO_2-MoO_3系中的一些Magneli相在本研究条件下不能作为热力学稳定相而存在.并绘制了400-700℃下Mo-O系相图.     

三元体系γ′相和θ相沉淀早期计算机研究

基于三元合金沉淀动力学相场方程的微观离散格点形式建立模型。首次对Ni75Al11V14合金的γ′和θ2个有序相析出的早期过程进行了模拟，并计算了γ′有序相的成分序参数和长程序参数。结果表明：Ni75Al11V14合金中γ′相的沉淀机制为非经典形核长大兼有失稳分解特征，先形成非化学计量比有序相，然后才形成化学计量比有序组；非化学计量比θ有序相在γ′相界处形成，距离γ′相界越远，其有序程度越低，θ有序畴存在2种类型：水平分布和垂直分布，和它所依附的γ′相界面取向有关。     

热平衡条件约束的推力磁轴承设计参数优化

本文阐述了一种推力磁轴承热平衡条件约束的设计参数优化的有效算法，约束包括外载荷、热平衡、电磁匹配和几何条件。系统设计变量为磁铁内环外径，外径内径。槽口深度和安匝数，还对系统参数作了灵敏度分析，一个高速透平主轴用推力磁轴承的应用实例表明：影响轴承承载力的主要因素是安匝数，静态气隙和槽口截面积，受热平衡和几何条件的限制，静态气隙和槽口面积的可调整范围较小，而适当增大绕组匝数和控制电流，可以显著提高承载力。     

Analysis of Intermetallic Phases Formed on Surface Vapor Oxidized H13 Hot Work Steels in Molten Aluminum

In this paper, the author dipped surface vapor oxidized H13 steel specimens into 700℃ molten aluminum liquid for a certain period of time. Analyze the intermetallic phases formed on the H13 samples surface with optical microscope and X-ray diffraction method. The observation of immersion test sample's cross-section shows that Fe3O4 film will protect die substrate from molten aluminum erosion. The identification of the intermetallic phases reveals that they consist of 2parts, which is named as the composite layer and the compact layer. Further investigations are made in order to know the phase constituents of the 2 layers, they are Al8Fe2Si (outer composite layer), (AlCuMg) and Al5Fe2 (compact layer),respectively. The experimental results show that on the same specimen, a convex surface with bigger radius of curvature is more likely to be molten and the melting loss speed is also faster than a flat and smooth surface. The thickness of compact layer on a smooth surface is much bigger than that of the convex surface. Therefore, the author supposes the compact layer is favorable in stabilizing the die surface material from further melting loss, as their formation on the die surface, the melting loss speed will decrease.     

氰化氢在终冷塔中气液两相之间转移的研究

分析了煤气中氰化氢的形成,论述了氰化氢在煤气和其冷凝液中的平衡机理,讨论了影响氰化氢相平衡的因素,研究了直接终冷、间接终冷时煤气中氰化氢的转移情况。