材料期刊网

THE ACCURATE MOLECULAR FORMULA OF "Ti_(11)Ni_(14)" PHASE

C.L. Chu , G.J. Shen , S.D. Wang , B. Li , S.G. Zhang and Z.D. Yin(BOX 433 , School of Materials Science and Engineering , Harbin Institute of Technology , Harbin 150001 , China)(Analysis and Testing Center , Southeast University , Nanjing 210018 , China)(Research Institute of Electric Light Source Materials , Ministry of Light Industry , Nanjing 210015 , China)

金属学报(英文版)

From the orientation relationship between "Ti11Ni14" phase and matrix phase (B2),the accurate molecular formula of "Ti11N14" phase has been derived in this paper. The results also show that the rhombohedral unit cell of the "Ti11Ni14" phase includes six Ti atoms, seven Ni atoms and one vacancy, belonging to space group R3.

关键词: TiNi , null , null

Response to the Comment on 'Conjectures on exact solution of three-dimensional (3D) simple orthorhombic Ising lattices'

Philosophical Magazine

The error of Equation (15b) in my article [Z.D. Zhang, Phil. Mag. 87 (2007) p.5309] in the application of the Jordan-Wigner transformation does not affect the validity of the putative exact solution, since the solution is not derived directly from that equation. Other objections of Perk's comment [J.H.H. Perk, Phil. Mag. 89 (2009) p.761] are the same as those in Wu et al.'s comments [F.Y. Wu et al., Phil. Mag. 88 (2008) p.3093; p.3103], which do not stand on solid ground and which I have sought to refute in my previous response [Z.D. Zhang, Phil. Mag. 88 (2008) p.3097]. The conjectured solution can be utilized to understand critical phenomena in various systems, whereas the conjectures are open to rigorous proof.

关键词: 3D Ising model;exact solution;conjecture;critical phenomena;ferromagnetism;magnetic phase transition;model;analyticity

Three-dimensional (3D) Ising universality in magnets and critical indices at fluid-fluid phase transition

Phase Transitions

Experimental data for critical exponents in some magnetic materials are compared with recent theoretical results on the three-dimensional (3D) Ising model, as derived by one of us (ZDZ) based on two conjectures [Z.D. Zhang, Conjectures on the exact solution of three-dimensional (3D) simple orthorhombic Ising lattices, Phil. Mag. 87 (2007), pp. 5309-5419]. It is found that critical exponents in some bulk magnetic materials indeed form a 3D Ising universality. Our attention is then focused on the critical indices at fluid-fluid phase transition. We suggest to use Zhang's exponent = 3/8 to fit the experimental data over the wider asymptotic region near the critical point of a fluid-fluid phase transition. The 3D Ising universality should exist for critical indices in a certain class of magnets and at fluid-fluid phase transition.

关键词: magnetically ordered materials;fluid-fluid;phase transitions;order-disorder effects;ferromagnetic curie temperature;liquid critical phenomena;x-ray-scattering;critical exponents;critical-point;coexistence;curves;binary-solutions;ionic-solutions;behavior;equation

PIP工艺制备2D C/SiC复合材料Z-向穿刺工艺

王其坤 , 胡海峰 , 陈朝辉 , 张玉娣 , 罗征

稀有金属材料与工程

针对2D C/SiC复合材料存在碳布层间缺乏纤维增强,层间结合较差的问题,提出通过Z-向穿刺工艺提高碳布层间结合,克服材料使用时可靠性不高的问题,并比较了穿刺工艺对复合材料微观结构和力学性能的影响.结果表明,通过Z-向穿刺工艺制得试样2D C/SiC-Z_(pin)的弯曲强度、弯曲模量和剪切强度分别为247.8 MPa、37.8 GPa和32.1 MPa,而未穿刺试样2D C/SiC的弯曲强度、弯曲模量和剪切强度分别只有219.3 MPa、34.4 GPa和23.3 MPa,由此可见,采用Z-向穿刺工艺能明显提高复合材料的力学性能.微观结构分析认为,试样力学性能提高的根本原因在于采用Z-向穿刺纤维加强了碳布层间结合,使材料具有较好的整体性,克服了复合材料层间结合较弱对力学性能带来的不利影响.

关键词: 2D , C/SiC , Z-向穿刺 , 微观结构 , 力学性能

Explanations of the optical spectra and g factor for V3+ ions in ZnX (X = S, Se, Te) crystals

Physica B-Condensed Matter

This paper presents a cluster approach for the calculations of the absorption band positions and the g factor of d(2) tetrahedral cluster. In the approach, the different modifications of e and t(2) orbitals of d electrons and the contribution from the spin-orbit coupling of ligands to the EPR g factor due to the mixing of d(2) ions with the ligands are considered. The calculated band positions and g factor for ZnX : V3+ (X = S, Se, Te) crystals show good agreement with the observed values by using only two adjustable parameters. The contribution from the spin-orbit coupling of ligands to the g factor is discussed. (C) 1998 Elsevier Science B.V. All rights reserved.

关键词: crystal- and ligand-field theory;optical spectra;electron paramagnetic;resonance;spin-orbit coupling;V3+ ZnX (X = S, Se, Te);vanadium centers;znte crystals

邯钢冷轧厂成功生产IF钢DX56D＋Z

钢铁

近日,集团邯钢公司西区冷轧厂1号镀锌线成功生产出9卷主要应用于汽车面板及高档家电外板的IF钢DX56D＋Z、共70多t,产品的屈服强度、抗拉强度、伸长率和表面质量指标均达到客户要求,为批量生产打下了坚实基础。

关键词: 批量生产 , IF钢 , 冷轧厂 , 邯钢 , 汽车面板 , 屈服强度 , 抗拉强度 , 客户要求

β晶型成核剂改性纤维级聚丙烯Z30S

窦强 , 王斌

高分子材料科学与工程

研究了β晶型成核剂(酰胺化合物)成核改性纤维级聚丙烯Z30S的力学性能,进行了广角X射线衍射和DSC分析.发现成核改性后生成了β晶型聚丙烯,因而聚丙烯Z30S的冲击性能提高.通过纺丝-拉伸实验和对纤维进行广角X射线衍射分析、SEM观察,发现成核改性纤维在纺丝拉伸过程中发生了晶型转变,产生大量微孔隙.

关键词: 聚丙烯 , β晶型 , 成核剂 , 纤维

2D-C/SiC复合材料低温动态Z向压缩性能

叶龙海 , 邓琼 , 汤忠斌

复合材料学报

采用Hopkinson压杆试验装置,对2D-C/SiC复合材料进行了低温条件下的Z向动态压缩性能试验研究,低温条件通过控制酒精和液氮的配比系数得到,通过改变波形整形器几何尺寸的方法来实现恒应变率加载,以得到准确、可信的试验结果.试验结果表明:由于复合材料内部含有大量初始微缺陷,2D-C/SiC复合材料在低温动态加载条件下呈现伪塑性行为,其破坏时并未表现出典型的脆性破坏,而是在应力达到压缩强度时出现了显著的应变软化现象,在经历了较大的变形后才最终破坏.随着温度的降低,复合材料的动态Z向压缩强度增加,但失效应变减小.2D-C/SiC复合材料在低温环境下,其内部纤维和基体之间界面结合力增强,同时强的界面结合力可以导致高的压缩强度.

关键词: 陶瓷基复合材料 , Hopkinson压杆试验装置 , 低温 , 动态Z向压缩力学性能 , 界面强度

Z125与N234对NR和S-SBR硫化胶增强效果的比较

程俊梅 , 张萍 , 于广水 , 赵树高

宇航材料工艺 doi:10.3969/j.issn.1007-2330.2009.06.016

在比表面积相近的情况下,探讨白炭黑(Z125)及碳黑(N234)对天然橡胶(NR)和溶聚丁苯橡胶(S-SBR)硫化胶的抗割口增长能力及动态力学性能的影响.结果表明,Z125和N234对NR和S-SBR两种硫化胶的增强效果相差不大;NR硫化胶的抗割口增长能力明显好于S-SBR硫化胶;NR中填充Z125的抗割口增长能力好于N234且随疲劳次数的增加Z125的优势更加明显,而S-SBR中填充N234的抗割口增长能力好于Z125且两者的抗割口增长速率基本不随疲劳次数的增加而改变;Z125使NR和S-SBR硫化胶在0℃和70℃下的tanδ值分别低于N234增强相应硫化胶.

关键词: NR , S-SBR , 白炭黑 , 炭黑 , 动态力学性能 , 抗割口增长能力

TC11合金热变形行为及Z-D关系的研究

孙新军 , 白秉哲 , 顾家琳 , 陈南平

稀有金属 doi:10.3969/j.issn.0258-7076.2000.03.003

考察了具有淬火马氏体组织的TC11合金在热压缩变形时的力学行为及显微组织特征. 在各个变形温度和应变速率条件下, TC11合金的应力-应变曲线均表现出先硬化后软化的趋势, 最后都获得一种相对稳定的变形状态; 与此同时, 原始非等轴片层组织通过动态再结晶转变为等轴均匀的组织; 变形温度越低或变形速率越高, 变形应力就越高, 所获得的稳态晶粒尺寸就越小; 通过对实验数据分析后发现, TC11合金在相对高低温区和相对高温区变形分别具有不同的变形激活能并由此导致Z-D关系不同.

关键词: TC11合金 , 热变形 , 力学行为 , 显微组织 , Z-D关系