材料期刊网

R & D ACTIVITIES ON AEROSPACE MATERIALS IN KOREA

H.M. Kim(Korea Institute of Machinery and Materials , Korea Manuscript received 26 August 1996)

金属学报(英文版)

This paper briefly reviews research and development programs in Korean aerospace industry,with an emphasis on aircraft materials technology. International collaborations in these areas are outlined and the R & D activities are highlighted against the　background of the national economy.It is shown that the investment from government agencies and large enterprises has led to healthy development of aerospace materials industries in Korea.

关键词: :R & D , null , null , null

THE INFLUENCES OF Zn CONTENT AND COOLING RATE ON ASCAST MICROSTRUCTURE IN Al75% Mg ALLOYS

Q.Wu1)and S.B.Kang2) 1) Department of Material Science and Engineering , Nanjing University of Science and Technology , Nanjing , 210014 , China 2) Department of Material Engineering , Korea Institute of Mechanics and Materials , Changwon , Korea

金属学报(英文版)

Thesolidification processof Al 7 5% Mg Zn alloys wasstudiedin thepaper.The Zn contentand cooling rate werechanged andtheirinfluenceson as cast microstructure were measured by different methods. The solute segregation during nonequilibrium solidification process wascalculated byternary Scheilequation which wasin good agreement with experimentresulte.

关键词: aluminum alloy , null , null

The tendency of the market and technology of the magnetic materials in Korea

C.O.Kim , Y.Li

材料科学技术（英）

关键词:

The Tendency of the Market and Technology of the Magnetic Materials in Korea

材料科学技术（英）

关键词:

Quantitative Analysis for Monitoring Formulation of Lubricating Oil Using Terahertz Time-Domain Transmission Spectroscopy

Chinese Physics Letters

The quantitative analysis of zinc isopropyl-isooctyl-dithiophosphate (T204) mixed with lube base oil from Korea with viscosity index 70 (T204-Korea70) is presented by using terahertz time-domain spectroscopy (THz-TDS). Compared with the middle-infrared spectra of zinc n-butyl-isooctyl-dithiophosphate (T202) and T204, THz spectra of T202 and T204 show the weak broad absorption bands. Then, the absorption coefficients of the T204-Korea70 system follow Beer's law at the concentration from 0.124 to 4.024%. The experimental absorption spectra of T204-Korea70 agree with the calculated ones based on the standard absorption coefficients of T204 and Korea70. The quantitative analysis enables a strategy to monitor the formulation of lubricating oil in real time.

关键词: infrared-spectroscopy;dielectric-properties;zddp;water

热空气老化和热水老化对PC冲击性能的影响

詹茂盛 , 方义 , 王瑛 , 范荣峥

航空材料学报 doi:10.3969/j.issn.1005-5053.2000.04.010

在40℃和80℃环境中,分别对Bayer-PC、Japan-PC、Korea-PC三种聚碳酸酯缺口冲击试样进行了热空气老化和热水老化实验研究.在0～400h老化时间内,研究了这三种PC的热空气老化和热水老化对冲击强度和断面形貌的影响,讨论了PC热空气老化和热水老化机理.结果表明:老化前,Japan-PC、Korea-PC和Bayer-PC冲击强度分别为95kJ/m2、83 kJ/m2和55 kJ/m2;在40℃和80℃热空气老化后,三种PC冲击强度均有所下降,其中80℃热空气老化引起的降幅最大,热空气老化400h后的冲击强度顺序为Japan-PC>Korea-PC>Bayer-PC,在40℃热水老化后,三种PC的冲击强度几乎不受老化时间影响;在80℃热水老化后,三种PC冲击强度均有所下降,其中Bayer-PC降幅最小,Japan-PC次之,Korea-PC最大,但PC的平衡冲击强度大小与热空气老化的情况相同.由扫描电镜对冲击断面形貌观察可知,未老化的三种PC均以剪切屈服破坏机理为主,老化后的三种PC主要以银纹集中破坏机理为主.

关键词: 聚碳酸酯 , 热空气老化 , 热水老化 , 破坏形貌

聚碳酸酯的吸水规律及其吸水试样表面缺陷分析

詹茂盛 , 方义 , 范勇峥 , 王瑛

复合材料学报 doi:10.3321/j.issn:1000-3851.2001.01.006

在40℃、60℃、80℃和100℃的热水环境中，分别对Bayer-PC、Japan-PC、Korea-PC三种聚碳酸酯透明板材进行了热水老化实验研究。在老化时间0～200 h内，共取样9次，研究了三种PC在热水老化过程中的吸水规律、不同热水老化条件对PC表面微观破坏形貌的影响，讨论了PC热水老化机理。结果表明：PC的含水量随着时间的延长而增大，最终趋于平衡；温度越高，平衡含水量越大；时间越长或温度越高，PC吸水试样表面的微缺陷越多；由于PC的水解，导致平衡含水量Mm和扩散系数Dx的理论估算值低于实验值。

关键词: 聚碳酸酯 , 热水老化 , 平衡含水量 , 扩散系数 , 表面微观破坏