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原生QI成核中间相炭微球的结构

王成扬 , 姜卉 , 李鹏 , 郑嘉明

新型炭材料 doi:10.3969/j.issn.1007-8827.2000.04.003

以含有原生QI的煤沥青为原料,采用热缩聚方法制备出中间相炭微球.用扫描电子显微镜(SEM)观察了中间相炭微球的形貌和断面结构.经初步判断,在实验条件下原生QI成核煤沥青基中间相炭微球更倾向于"地球仪" 型结构.并对以QI为核形成中间相微球的过程进行了分析.

关键词: 原生喹啉不溶物 , 中间相炭微球 , 结构

煤沥青原料中QI含量对中间相有序生长的影响

黄爱华 , 金鸣林 , 李和兴 , 房永征

材料导报

试验是以2种含不同QI的煤沥青为原料,采用变径反应管进行热转化反应制备有序性中间相的研究.试验采用偏光显微镜和扫描电镜(SEM)观察了原料各反应阶段的微观结构,考察了QI对热转化过程中中间相有序生长的影响,分析了热转化过程中软化点及族组分的变化.结果表明:少量的喹啉不溶物含量不会阻碍中间相有序的发展.高QI(2.03%)原料易生成镶嵌结构的中间相体,高温处理后样品呈轴状、短纤维、层片松散的石墨化焦结构;含低QI(0.11%)的原料能生成较好的、大区域的中间相体,域结构的中间相体在外力导向和内部裂解气流的作用下容易生成有序的半焦,高温处理后呈大区域、片层紧密、有序性强的细纤维焦结构.同时研究发现,在热转化过程中可通过测定软化点(SP)和TI含量来确定中间相转化程度.软化点约低于250℃、TI为75%左右时为初始中间相区域体形成阶段、半焦生成的前期.

关键词: 煤沥青 , 热转化反应 , 喹啉不溶物 , 中间相

高软化点各向同性沥青和各向异性沥青中喹啉不溶物的结构研究

刘小红 , 王成扬 , 陈明鸣 , 于宝军

材料导报

以软化点相近的高软化点各向同性沥青和各向异性沥青为原料,经溶剂萃取分离出喹啉不溶物(QI),采用偏光显微镜、扫描电镜、元素组成分析、碘吸附测试和X射线衍射分析,对各向异性沥青的光学织构、QI的形貌及其微观结构进行了分析.结果表明,不同原料来源的各向异性沥青会表现出不同的光学各向异性.对高软化点沥青QI的分析表明,虽然母体沥青的软化点相近,但是具有不同光学各向性的沥青分离出的QI在形貌和微观结构上有较大的差异,各向异性沥青QI的分子交联度、芳香度和缩合度均比各向同性沥青QI小,但是平面分子结构更规整,有序度更高.同时发现,当沥青为各向同性时,母体沥青的分子有序度不如QI高,但当沥青为各向异性时,母体沥青的有序度却高于QI.

关键词: 各向同性 , 各向异性 , 高软化点 , 喹啉不溶物

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

炭/炭复合材料用高性能浸渍剂沥青的研究

许斌 , 李铁虎

复合材料学报 doi:10.3321/j.issn:1000-3851.2003.02.013

根据原生QI杂质由微米级炭粒构成的特性,采用溶剂絮凝法对煤焦油进行了净化处理,以净化煤焦油为原料制备了低QI含量的高性能浸渍剂沥青,对比研究了高性能浸渍剂沥青的流变性能和渗透性能.结果证实:高性能浸渍剂沥青极大地改善了浸渍效果,并且使炭/炭复合材料的力学性能显著提高.

关键词: 炭/炭复合材料 , 浸渍剂沥青 , 原生QI杂质 , 粘度 , 渗透性 , 性能

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

中温煤沥青喹啉不溶物的脱除及炭化制备针状焦

唐闲逸 , 魏晓慧 , 许德平 , 张海永 , 贺欣 , 熊楚安 , 唐瀚滢

材料研究学报 doi:10.11901/1005.3093.2015.685

以中温煤沥青为原料,研究其在弹管反应器中的炭化以及“反溶剂法”脱出喹啉不溶物(QI)后的精制沥青的炭化效果.结果表明:含有较高QI的非精制沥青不能制备出较好的针状焦,但在500℃,0.2 MPa,10h的炭化条件下,能够得到相对较优热膨胀系数(CTE)的炭化结果;以煤油和洗油为混合溶剂,反溶剂法能够有效地脱除喹啉不溶物,在芳脂比0.4,沉降温度100℃,搅拌时间0.5 h,沉降时间4h,溶剂比1.8、2的条件下,QI含量分别降到0.0914%和0.0695%,将其在500℃、0.2 MPa、10h的条件下炭化,可制备出热膨胀系数(CTE)较低的针状焦.

关键词: 材料合成与加工工艺 , 中温煤沥青 , 反溶剂法 , 喹啉不溶物 , 炭化 , 针状焦

Sputtering Rates of Alloys in Glow Discharge

Jianshi REN and Gongshu ZHANG (Institute of Metal Research , Chinese Academy of Science , Shenyang , 110015 , China)Zhenshu WANG and Jinwei ZHAO (Shanghai University of Technology Shanghai , 200072 , China)

材料科学技术(英文)

The sputtering rates of alloys were investigated under constant Ar pressure and voltage supplied.The alloys studied in this work range from binary intermetallic alloys to ternary and quaternary alloys. It is revealed that the sputtering rates of alloy targets under steady states are where q is the sputtering rates of alloys, Ci the weight percentage of i-th component in the alloy,and qi0 the sputtering rate of pure metal of i-th component.

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