材料期刊网

Effects of Temperature and Atmosphere on Pellets Reduction Swelling Index

WANG Zhao-cai , CHU Man-sheng , LIU Zheng-gen , CHEN Shuang-yin , XUE Xiang-xin

钢铁研究学报(英文版)

After taking into account the conditions of the domestic iron resources and the non-coking coal resources, the process of coal gasification-shaft furnace is an effective way to develop direct reduction iron in China. The following tasks are very critical to choose suitable process of shaft furnace and gasification, including the production of oxidized pellets with excellent comprehensive properties as well as the study of the reaction behavior and mechanism of swelling. The results showed that the oxidized pellets of using domestic magnetic iron concentrate as raw materials have favorable comprehensive properties, including higher mechanical strength both before and after reduction, faster reduction rate and lower reduction swelling index (RSI). All of these properties can meet the shaft furnace yielding requirement. When the temperature was below 1223 K, the pellets′ RSI was lower than 20%. With increasing of the content of H2 in atmosphere, the pellets reaction rate accelerated, crushing strength enhanced and RSI decreased. The RSI dropped to 10.26% at 1323 K in 100% H2 atmosphere, and it is up to 39.88% in 100% CO atmosphere. The iron grains mainly presented in platelike when pellets were reduced by H2, however, in CO atmosphere the iron grains were precipitated in flocculent. The whisker shape of iron grains and heating effects of reduction reaction are the major factors leading to the poor pellets strength and increase of RSI. Appropriately controlling the temperature and increasing the ratio of H2 to CO in atmosphere are good for dropping the RSI.

关键词: oxidized pellet , shaft furnace , direct reduction , reduction swelling

复合材料层合壳体的三维本构方程

杨宜谦

玻璃钢/复合材料 doi:10.3969/j.issn.1003-0999.1999.04.002

本文推导出了复合材料层合壳体的三维本构方程,修正了Reddy和Liu论文中的错误.

关键词: 复合材料 , 壳体 , 三维本构方程

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

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:

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

镧-依文思蓝-氨基糖苷类抗生素的显色反应及其分析应用

江虹 , 胡小莉 , 刘绍璞 , 秦宗会 , 湛海粼

应用化学 doi:10.3969/j.issn.1000-0518.2003.09.016

在pH值为3.5～6.0,镧(Ⅲ)-依文思蓝(EB)与硫酸新霉素(NEO)、硫酸卡那霉素(KANA)、硫酸庆大霉(GEN)和硫酸妥布霉素(TOB)等氨基糖苷类抗生素反应可生成具有吸收峰和负吸收峰的三元蓝色离子缔合物.其最大吸收波长位于668～674 nm,线性范围从0～1.20×10-5g/mL至0～1.加×10-5g/mL,摩尔吸收光系数(ε)在3.10×104～6.17×104L/(mol@cm)之间;最大负吸收波长位于614～620 nm,线性范围从0～9.00×10-6g/mL至0～1.7×10-5g/mL,摩尔吸收光系数(ε)在4.33×104～1.04×105L/(mol@em).当用正负光吸收叠加时,灵敏度更高.探讨了反应条件、主要分析化学性质及三元缔合物的配合比(LA:EB:GEN=1:2:3).

关键词: 镧(Ⅲ),依文思蓝,氨基糖苷,抗生素,分光光度法

聚醛/蒙脱土纳米复合材料非等温结晶动力学研究

徐卫兵 , 戈明亮 , 何平笙

应用化学 doi:10.3969/j.issn.1000-0518.2001.09.011

用熔融插层法制备聚甲醛/蒙脱土纳米复合材料,用X射线衍射研究聚甲醛及复合材料的微观结构,表明复合材料是纳米复合材料.用DSC法研究其非等温结晶行为,对所得数据分别用Jeziorny法、Ozawa法和Liu法进行处理.结果表明,Jeziorny法和Liu法处理非等温结晶过程比较理想.聚甲醛及聚甲醛/有机蒙脱土纳米复合材料的结晶活化能分别为334.6和196.9 kJ/mol,说明有机蒙脱土的加入,降低了聚甲醛的结晶活化能,且t1/z缩短,起到了异相成核的作用.

关键词: 聚甲醛 , 蒙脱土 , 纳米复合材料 , 非等温结晶动力学

聚丙烯/凹凸棒土纳米复合材料的非等温结晶动力学

王平华 , 徐国永

应用化学 doi:10.3969/j.issn.1000-0518.2004.08.007

用熔融复合法制备聚丙烯/凹凸棒土纳米复合材料,用DSC法研究其非等温结晶行为,对所得的数据分别用Jeziorny法、Ozawa法和Liu法进行处理.结果表明,Jeziorny法和Liu法处理非等温结晶过程比较理想.聚丙烯及聚丙烯/凹凸棒土纳米复合材料的结晶活化能分别为194.1和162.8 kJ/mol,表明凹凸棒土的加入,降低了聚丙烯的结晶活化能,且t1/2缩短,起到了异相成核作用.

关键词: 聚丙烯 , 凹凸棒土 , 纳米复合材料 , 非等温结晶动力学

FORMATION OF Fe—N COMPOUNDS BY LASER NITRIDATION IN AN ATMOSPHERIC AMBIENT

Y.L.Yang , F.J.Sun , D.Zhang

金属学报(英文版)

The formation of Fe-N compounds by laser nitriding in an atmospheric ambient was reported.By CW-CO2 laser irradiation on pure ferrite iron in the atmospheric am-bient,Fe-N compounds (including Fe2N,Fe3N and Fe4N) are formed as a result of a laser-enhanced and temperature-enhanced reactions.The samples were analyzed with X-ray diffraction.It is found that the laser power density,scanning speed and nitro-gen temperature are the main factors influencing the formation of Fe-N compounds.Nitrogen can be activated by pre-heating at some temperature.Nitrogen activation and sample surface melting by CW-CO2 laser greatly enhance the reaction between the sample surface and nitrogen beam.After annealing at 500℃ for Sh,some Fe2N and Fe3N converted into more stable Fe4N.

关键词: laser nitriding , null , null

Relationship between the Brittlement Susceptibility and H Permeation Current for UNS G11180 Steel in 5% NaCl Solution with H_2S

Xueyuan ZHANG and Yuanlong DU(State Key Lab. for Corrosion and Protection , Institute of Corrosion and Protection of Metals , Chinese Academy of Sciences , Shenyang 110015 , China)

材料科学技术（英文）

Sulfide stress corrosion cracking (SSCC) behaviour of UNS G11180 steel in 5% NaCl solution with H2S was studied by slow strain rate tensile test (SSRT), SEM and electrochemical hydro gen permeation technique. The results reveal different cracking mechanism and H permeation current (IH) through UNS G11180 steel plate in different concentration of H2S solution. The susceptibility to SSCC of UNS G11180 Steel in 5% NaCl solution with H2S was evaluated by the permeation current(IH, μA), which depends on the concentration (c×10-6) of H2S by the equation:IH = 8.525 ×c0.7249. lt is proved that the electrochemical H permeation method is a practical way to assess the susceptibility to SSCC.

关键词: