Xinchun CHANG
,
Jianqiang WANG
,
Nanlin SHI and Zhuangqi HU (State Key Lab. of RSA
,
Institute of Metal Research
,
Chinese Academy of Sciences
,
Shenyang 110015
,
China)Yijun DU
,
(Manufacturing Engineering Dept.
,
City University of Hong Kong
,
Kowloon
,
Hong Kong)
材料科学技术（英文）
An electrochemical sudece-treatment method has been used for modifying surface condition of large diameter CVD SiC (W core) fibers. The average tensile strength of the fibers was increased obviously from 2270.1 to 3002.9 MPa. X-ray photoelectron spectroscopy (XPS) studies on the treated fiber sudece indicate that a silicon-oxide film (primarily α-SiO2) has formed,accompanying the precipitation of amorphous carbon as the products of an anode oxidation reaction. In addition, the substantial increase of fiber strength through the electrochemical treatment may be described to the formation of oxide films and elimination of defects on the fiber surface.
关键词:
Hongwang YANG
,
Xinchun CHANG
,
Wanliang HOU
,
Jianqiang WANG
材料科学技术（英文）
Transmission electron microscopy (TEM) is usually used to identify the amorphicity. However, some artifacts may be introduced due to improper TEM foil preparation. In this paper, three Al-rich metallic glasses with and without a glass transition were selected for characterizing the effect of the electropolishing condition on the as-quenched structure during TEM specimen preparation. It is shown that the occurrence of the modulated bright-dark structure under TEM observation is closely sensitive to the electropolishing condition, which suggests us being careful about the possible artifacts induced by specimen preparation when examining amorphous alloys under TEM.
关键词:
Al-based amorphous alloy
,
null
,
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