材料期刊网

ELECTROCHEMICAL BEHAVIOUR OF PHASES IN TITANIUM ALLOYS

LIU Ping Institute of Aeronautical Material , Beijing , ChinaXU Changgan Beijing University of Aeronautics and Astronautics , Beijing , China XU Changgan , Associate Professor , Group 102 , Beijing University of Aeronautics and Astronautics , 37 Xueyuan Road , Beijing 100083 , China

金属学报(英文版)

The electrochemical behaviour,which is presented by means of anodic polarization curves.of the component phases in Ti and Ti alloys in aqueous solutions of fluorhydrie acid,chhnhydric acid and amber acid has been investigated.The results indicate that the electrochemical behaviour of the allloys depends upon the composition and the lattice type.The corrosion of x and x′phase in actire region and that of β phase in passive region are the dominant corrosion behaviour.

关键词: Ti alloy , null , null

RENORMALIZATION-GROUP OF GENERALIZED FIBONACCI LATTICES

Physical Review B

We investigate the renormalization group of the generalized Fibonacci lattices associated with the aperiodic sequences as constructed by the inflation rule: {A,B} --> {A(n)B(m),A}, in which m and n are positive integers. The derived renormalization group consists of 2n(n+m-1)+1 basic renormalization-group transformations. By suitable combinations of these basic transformations, local Green's function and local density of states at any sites can be calculated for electrons on the generalized Fibonacci lattices. The off-diagonal model is employed, and the local electronic densities of states at several sites are numerically calculated for some generalized Fibonacci lattices.

关键词: one-dimensional quasicrystals;quasi-periodic systems;electronic-properties;green-functions;phonon properties;energy-spectra;wave-functions;dynamic maps;localization;tilings

淬火剂SST102的冷却特性

王刚 , 田旭东 , 刘向左

物理测试 doi:10.3969/j.issn.1001-0777.2005.03.007

对SST102淬火剂的冷却特性进行了探讨.结果表明,SST102的冷却能力随其浓度的增大、温度的升高及重复使用次数增多而降低.并揭示了该介质在冷却金属时能在金属表面形成一层聚合物隔离膜,此膜能避免因零件几何形态差异造成的冷却不均匀现象,有效地防止开裂和变形.

关键词: SST102淬火剂 , 冷却特性 , 影响因素

Renormalisation Group of Two-dimensional Decagonal Tilings

Xiaohong YAN , Jianwen DING , Qibin YANG , Bruno Iochum

材料科学技术（英文）

We present a new series of two-dimensional decagonal tilings which are connected with each in five transformation rules. In this case, a real-space renormalization group scheme is developed to study physical properties of the decagonal systems in terms of Green's function theory.

关键词:

Derivation of subgroup network of three-dimensional crystallographic symmetry group

Acta Physica Sinica

The subgroup network of the three-dimensional crystallographic symmetry group has been derived based on the two maximal finite groups corresponding to two geometrically inequivalent classes. First, the geometrical meaning of every group element of these two maximal finite groups was analysed, then all the subgroups of them was derived according to the relationship between supergroup and subgroup. Tire advantages of algebraic crystallography based on quadratic form theory were discussed.

关键词: quadratic form;isomorphism;equivalent class

淬火介质SST102在调质钢热处理中的应用

钟长文 , 刘建华 , 王海燕 , 呼文来

物理测试 doi:10.3969/j.issn.1001-0777.2000.01.005

研究了调质钢40Cr在淬火介质SST102中淬火后的淬透性,变形开裂性及力学性能.实验结果表明,适当调整SST102的浓度,可以获得不同的冷却速度,作为调质钢40Cr淬火介质的最佳浓度为1.0%～1.5%.

关键词: 淬火介质 , 浓度 , 调质钢

RENORMALIZATION-GROUP APPROACH TO THE RANDOM PERIOD-DOUBLING LATTICE

Physics Letters A

Using an exact real space renormalization group technique, we have studied the local electronic properties of a class of one-dimensional aperiodic random lattice models. The perfect chain, of which the substitution rules are A --> AB and B --> AA, is considered as a particular case.

关键词: schrodinger-equation;localization;fibonacci;spectrum;systems;rules

Spectral properties of the period-doubling lattice: Exact renormalization group study

Zeitschrift Fur Physik B-Condensed Matter

Using an exact real space renormalization group technique, we have studied the electronic and vibrational properties of a class of one dimensional aperiodic lattice model, for which the substitution rules are A --> AB and B --> AA. The spectra are self-similar and exhibit hierarchical structures. Analytical and numerical analyses reveal the existence of extended eigenstates.

关键词: transfer-matrix methods;schrodinger-equation;fibonacci;systems;localization;crystals;states;rules

钛酸型A102焊条抗裂性试验研究

张婉云 , 肖勇 , 李占坚 , 蒋成刚

材料开发与应用 doi:10.3969/j.issn.1003-1545.2008.05.005

对钛酸型A102焊条和钛钙型A102焊条进行的抗裂性比较试验结果表明,在同等条件下均未发现焊接热裂纹,即抗裂性能处于同一水平.从焊缝中的铁素体含量、氧含量及硅含量的试验结果得到,不同类型A102焊条焊缝中铁素体含量和氧含量基本相同,硅含量符合国标要求.这证明了焊条抗裂性试验结果的可靠性和对其结果评价的正确性.

关键词: 钛酸型 , A102焊条 , 抗裂性

挤压GW102镁合金组织和力学性能

陈庆荣 , 杨忠 , 李建平 , 吴永兴 , 刘继林 , 杨志玲

材料研究学报

研究了Mg-9.8Gd-1.6Y-0.02Zn-0.5Zr(GW102)镁合金挤压棒材的显微组织和不同方向的拉伸性能.结果表明,经520℃均匀化处理的GW102镁合金的组织主要由过饱和镁固溶体、少量凝固期间析出的颗粒相Mg5(Y06Gd04)和非平衡相Mg3(Gd05,Y05)组成.挤压变形并在200℃时效热处理60h后,从过饱和固溶体中弥散析出大量针片状β"相和β"相.该镁合金经过挤压变形后具有明显的各向异性,垂直挤压方向合金的抗拉强度显著低于挤压方向的抗拉强度和延伸率.GW102合金的强化,其主要原因是长周期结构相(LPSO)与位错的相互作用和晶界上无沉淀析出带的影响.

关键词: 金属材料 , GW102镁合金 , 挤压 , 显微组织 , 力学性能