欢迎登录材料期刊网

材料期刊网

高级检索

  • 论文(8)
  • 图书()
  • 专利()
  • 新闻()

Morphology and Precipitation Kinetics of MnS in LowCarbon Steel During Thin Slab Continuous Casting Process

YU Hao , KANG Yonglin , ZHAO Zhengzhi , SUN Hao

钢铁研究学报(英文版)

The morphology of manganese sulfide formed during thin slab continuous casting process in lowcarbon steel produced by compact strip production (CSP) technique was investigated. Using transmission electron microscopy analysis, it was seen that a majority of manganese sulfides precipitated at austenite grain boundaries, the morphologies of which were spherical or close to the spherical shape and the size of MnS precipitates ranged from 30 nm to 100 nm. A mathematical model of the manganese sulfide precipitation in this process was developed based on classical nucleation theory. Under the given conditions, the starting and finishing precipitation temperatures of MnS in the continuous casting thin slab of the studied lowcarbon steel are 1 189 ℃ and 1 171 ℃, respectively, and the average diameter of MnS precipitates is about 48 nm within this precipitation temperature range. The influences of chemical components and thermomechanical processing conditions on the precipitation behavior of MnS in the same process were also discussed.

关键词: morphology;thin slab continuous casting;precipitation kinetics;compact strip production;TEM

1998 COMPREHENSIVE TABLE OF CONTENTS

中国腐蚀与防护学报

N。1Atmospheric Corrosivlty for Steels………………………………………………… .LIANG Caideng HO[I i。-tat(6)Caustic Stress Corrosion Cr。king of Alloy 800 Part 2.The Effect of Thiosul执e……………………………………… KONG De-sheng YANG Wu ZHAO Guo-zheng HUANG De.ltL。ZHANG Yu。。he CHEN She。g-bac(13)SERS slid E16CttOCh6iniC81 Stlldy Of Illhibit1Oli M6ch&tllsth Of ThlollY68 Oil ITOll ID H....

关键词:

3 0CrMnSi 2A钢飞机主梁疲劳断裂分析

马康民 , 宣建光 , 康进兴

材料工程 doi:10.3969/j.issn.1001-4381.2001.10.012

用扫描电镜观察了某型飞机机翼主梁的疲劳断口,用疲劳条带估算了裂纹扩展寿命,并用Zheng-Hirt公式估算出裂纹尖端应力强度因子范围,估算结果与实验测定值十分接近,从而为研究老龄飞机的使用寿命,进行了有益的探索.

关键词: 机翼主梁 , 30crMnSiNi2A , 疲劳裂纹扩展寿命

Noncollinear magnetic ground state of PrFeAsO

Europhysics Letters

Noncollinear magnetic investigations of the ground state in PrFeAsO have been performed by the density-functional theory. We calculated the total energy and made structure optimization, and the electronic density of states of PrFeAsO was analyzed. There are three different magnetic structures in PrFeAsO defined by experiments. Based on these magnetic structures, we studied four collinear and four noncollinear cases. The ground state is found to take the ordering proposed by Zhao, in which the FeAs plane is of stripe antiferromagnetism and Pr spins are perpendicular to Fe spins. The electronic density of states indicates that for PrFeAsO the increase of the electron Coulomb interaction leads to a decrease in conductivity. Copyright (C) EPLA, 2011

关键词: high-temperature superconductivity;phase-diagram;oxypnictides;instability

Monte Carlo simulation of angular distribution and fractionation in the zero-fluence isotope sputtering

Nuclear Instruments & Methods in Physics Research Section B-Beam Interactions with Materials and Atoms

A static Monte Carlo simulation program has been used to study the influence of primary and secondary knock-on atoms on the angular distribution and the fractionation, for zero-fluence sputtering of Mo-92-Mo-100. At 10 keV Xe ion energy, calculations show that significant depth-dependent momentum asymmetry exists in the near-surface region, as in Refs. (L.P. Zheng, R.S. Li, M.Y.LI, Nucl. Instr, and Meth. B 100 (1995) 490; L.P. Zheng, M.Y. Li, Nucl. Instr. and Meth. B 114(1996) 28). The calculations also show that at the polar emission angle range between 0 degrees and 90 degrees the probabilities of the sputtered primary knock-on atoms for Mo-92 and Mo-100 are small (6.1% for Mo-92 and 6.6% for Mo-100), especially, between 0 degrees and 30 degrees they are very small (2.5% for Mo-92 and 2.8% for Mo-100). At 0.1 keV Ar ion energy, the calculations show that partial momentum flux ratios, for the primary and the secondary knock-on atoms, deviate far from one, through marker plane 1 (about an atomic layer distance from the surface). (C) 1998 Elsevier Science B.V. All rights reserved.

关键词: mo-92-mo-100;targets

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

硝酸羟胺的热稳定性评估及热分解机理研究

刘建国 , 安振涛 , 张倩 , 杜仕国 , 姚凯 , 王金

材料导报 doi:10.11896/j.issn.1005-023X.2017.04.030

为评估氧化剂硝酸羟胺的热稳定性,使用标准液体铝皿于3 K/min、4 K/min、5 K/min加热速率下进行热分析.借助非等温DSC曲线的参数值,应用Kissinger法和Ozawa法求得热分解反应的表观活化能和指前因子,根据Zhang-Hu-Xie-Li公式、Hu-Yang-Liang-Xie公式、Hu-Zhao-Gao公式以及Zhao-Hu-Gao公式,计算硝酸羟胺的自加速分解温度和热爆炸临界温度,并对热分解机理函数进行了研究.设计了7条热分解反应路径,采用密度泛函理论B3LYP/6-311++G(d,p)方法对硝酸羟胺的热分解进行了动力学和热力学计算.计算结果表明,硝酸羟胺热分解的自加速分解温度TsADT=370.05 K,热爆炸临界温度Te0=388.68K,Tbp0=397.54 K,热分解最可几机理函数的微分形式为f(a) =17×(1-α)18/17.硝酸羟胺热分解各路径中,动力学优先支持路径Path 6、Path 5、Path 4和Path 1生成NO和NO2,其次是Path 2、Path 7和Path 3生成N2和N2O.温度在373 K以下时,Path 1'反应无法自发进行,硝酸羟胺无法进行自发的热分解.从热力学的角度来看,硝酸羟胺在370.05K以下储存是安全的.

关键词: 硝酸羟胺 , 热分析 , 热稳定性 , 热分解机理 , 密度泛函理论

Fe80Si9B11非晶合金薄带热膨胀特性和结构弛豫分析

李红 , 孙克 , 李艳萍 , 石毅 , 郭金花 , 卢志超

金属功能材料

提出了采用推杆式热膨胀仪测试非晶合金薄带热膨胀特性的新方法.分析了Fe80Si9B11非晶薄带的热膨胀曲特性和非晶合金晶化过程.根据R.G.Zheng理论分析了结构弛豫中自由体积比变化,发现自由体积比曲线出现双峰.结合晶化前发生相分离的理论分析了这种变化的原因.分析表明:铁基非晶Fe80Si9B11晶化过程中先形成α-Fe(Si)相,再析出Fe3B、二次α-Fe(Si)相.晶化前先发生相分离,自由体积比增大,然后析出结晶相α-Fe(Si),自由体积比降低.随温度升高,B偏聚,自由体积比增大,随后析出Fe3B、二次α-Fe(Si)相,自由体积比降低.

关键词: 铁基非晶薄带 , 热膨胀系数 , 自由体积比 , 结构弛豫

出版年份

刊物分类

相关作者

相关热词