材料期刊网

Impact parameter dependence of the scaling of anisotropic flows in intermediate energy heavy-ion collisions

YAN Ting-Zhi , LI Shan

中国物理C doi:10.1088/1674-1137/38/8/084104

关键词:

RHEOLOGICAL BEHAVIOURS OF CAST STEEL DURING SOLIDIFICATION

LIN Jialiu ZHU Shigen YU Zhenzong Tsinghua University , Beijing , China

金属学报(英文版)

The stress-strain relation for cast low alloy carbon steel at solidification temperature has been examined by the authors' own desingned apparatus for rheological properties measurement.The rheology model,the stress-strain constitutive equation and the rheological parameters therefrom of the cast steel were proposed.Thus the theoretical basis and calcula- ting data for computerized s#nulation on the stress-strain relation and thermal cracking of the cast steel were suggested.

关键词: rheological behaviour , null , null , null , null

Cu-Zr/ZrN薄膜体系的电阻率和纳米压入研究

白宣羽 , 汪渊 , 徐可为

稀有金属材料与工程

采用磁控溅射方法在Si(111)基片上沉积Cu-Zr/ZrN薄膜体系作为扩散阻挡层.通过比较Cu-Zr/ZrN薄膜体系和三元非晶(Mo,Ta,W)-Si-N的电阻率,同时比较Cu-Zr/ZrN薄膜体系和Ta,YaN的硬度,说明作为扩散阻挡层的材料的选取,应从整体性能上考虑,而不能仅仅考虑热稳定性等单一指标.

关键词: 非晶 , 电阻率 , 纳米压入 , 硬度

FRACTAL GEOMETRY STUDY OF CORRELATION BETWEEN IMPACT TOUGHNESS OF STEEL AND PARAMETERS OF FREE-CUTTING PHASE

JIANG Laizhu CUI Kun Huazhong University of Science and Technology , Wuhan , China

金属学报(英文版)

Studies were made of the calculation of fractal dimension of transverse impact fracture sur- face,and of the correlation between impact toughness of steel and parameters of free-cutting phase by means of the developed fractal geometry model of crack propagation.It is believed that the area fraction,f,of free-cutting phase is negligibly influential to the longitudinal im- pact toughness,as f1 .While the aspect ratio,saying ratio of length to width,of free-cut. ting phase is inversely influential to the transverse impact toughness.This may .be the reason why the transverse impact toughness of free-cutting steel containing more rare earth contrast to sulphur is even higher than the low sulphur containing steel.

关键词: fractal geometry , null , null

FRICTION MARTENSITE AND ITS TEMPERING CHARACTERISTICS

Liu Zhengyi Fu Jian Zhuang Yuzhi South China University of Technology , Guangzhou , China Correspondent:LIU Zhengyi professor , Dept.of Mechanical Engineering No.2 , South China University of Technology , Guangzhou , China

金属学报(英文版)

The nature of“white layer”found in 55SiMnMo steel subjected to friction test has been stu- died using TEM,SEM,X-ray diffraction and EPMA techniques.It is shown that the struc- ture of the“white laver”on the rubbing surface is duplex,consisting of a special martensite and some austenite.This layer may be 25—50 μm thick.It is ultrafine,with grain diametric approximately 30 nm.Its micro-hardness may be as high as Hm 1500 and is capable of cut- ting glass.It has superb corrosion resistance and resists tempering.Its mierostructure and hardness undergo changes only when the steel is tempered above 500℃.

关键词: friction , null , null

LC4铝合金稀土转化膜耐蚀性及影响因素

张巍 , 李久青 , 许江涛 , 陈昆

腐蚀学报（英文） doi:10.3969/j.issn.1002-6495.1999.06.004

开发了IC4铝合金稀土转化膜碱性两步成膜工艺ZH1,利用正交优化设计方法确定了最佳工艺参数.采用多种实验方法研究了经ZH1处理的LC4铝合金在氯化物环境中的耐蚀性及其影响因素,结果表明:经ZHI工艺处理过的LC4铝合金耐全面腐蚀和点蚀性能均有明显提高,稀土转化膜既抑制了腐蚀的阴极过程,也抑制了阳极过程.具有ZH1转化膜的LC4铝合金对氯离子浓度和pH值的变化不甚敏感.

关键词: 高强铝合金 , 稀土转化膜 , 耐蚀性学科

Studies of the g factors and the local structure for Ni3+in LaAl0.9Ni0.1O3, La0.75Y0.25Al0.99Ni0.01O3 and YAl0.9Ni0.1O3

Radiation Effects and Defects in Solids

The electron paramagnetic resonance g factors and the local structure for Ni3+ in LaAl0.9Ni0.1O3 (LAN), La0.75Y0.25Al0.99Ni0.01O3 (LYAN) and YAl0.9Ni0.1O3 (YAN) are theoretically studied from the perturbation formulas of the g factors for a 3d7 ion of low spin (S = 1/2) in tetragonally elongated octahedra. In these formulas, the contributions to the g factors from the tetragonal distortion, characterized by the tetragonal field parameters Ds and Dt are taken into account. According to the calculations, the ligand octahedra around Ni3+ are suggested to suffer 2% relative elongation along the [001] (or C4) axis due to the Jahn-Teller effect.

关键词: defect structures;electron paramagnetic resonance;crystal-fields and;spin Hamiltonians;Ni3+;LaAlO3;LaYAlO3;YAlO3;atomic screening constants;optical-spectra;paramagnetic-resonance;superconducting tapes;lattice-distortions;superposition model;scf;functions;cr3+ ions;crystals;epr

非微扰QCD和核遮蔽效应对K因子的影响

智海素 , 侯召宇

原子核物理评论 doi:10.3969/j.issn.1007-4627.2006.01.002

考虑非微扰量子色动力学物理真空夸克凝聚效应,计算了碳核与碳核在质心系能量分别为630和200 GeV时碰撞Drell-Yan过程的K因子,以及加入核遮蔽因子后非微扰效应对K因子的影响,并把计算结果与没有考虑夸克凝聚非微扰效应的K值进行了对比.结果表明,非微扰效应和核遮蔽效应对K因子影响很小.

关键词: K因子 , Drell-Yan过程 , 夸克凝聚 , 非微扰量子色动力学 , 核遮蔽效应

含Nb-Ti低碳微合金钢中纳米碳化物的相间析出行为

李小琳 , 王昭东

金属学报 doi:10.11900/0412.1961.2014.00582

采用热膨胀实验研究了等温温度对Nb-Ti微合金钢组织、性能及析出行为的影响规律,利用TEM对不同温度等温后试样的析出行为进行观察和分析.结果表明,不同温度等温后试样中均可观察到相间析出碳化物,且降低等温温度可显著细化相间析出碳化物所在面面间距、相间析出碳化物所在面内析出物间距及相间析出碳化物尺寸.具有层状分布特征的相间析出碳化物所在面呈现弯曲和平直2种形态,其中平直型相间析出碳化物所在面平行于铁素体的{011},{012},{013}和{035}面.经HRTEM确定相间析出碳化物具有NaC1型晶体结构,晶格常数为0.434 nm,且与铁素体基体符合Baker-Nut-ting(B-N)关系,经EDS分析确定相间析出碳化物为(Nb,Ti)C.利用Orowan机制对析出强化量进行估算,结果表明不同等温温度下析出强化量均大于300MPa.

关键词: Nb-Ti微合金钢 , 相间析出 , Vickers硬度 , 高分辨透射电子显微术 , 取向关系 , 错配度