X.H. Yang
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P. Xiao
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S.H. Liang
,
J.T. Zou
,
Z.K. Fan
金属学报(英文版)
By the sessile drop technique, the wettability of Cu/W systems with the additions of Ni and Cr has been studied under vacuum atmosphere. Effects of Ni and Cr contents and wetting temperatures on the wettability and the wetting mechanisms of copper on W substrate have been investigated in detail. The results show that the wetting angles of Cu on the W substrate are decreased with an increase in the content of Ni or Cr, and also decrease with raising the wetting temperatures. SEM, EPMA, and X-ray diffraction have been used to analyze the interfacial characteristics of the
CuNi/W and CuCr/W systems. The results reveal that there is a transition layer about 2--3~$\mu$m in the interface of Cu-4.0 wt pct Ni/W, in which the intermetallic phase Ni4W is precipitated. As to CuCr/W system, no reaction occurs at the interface. The two factors are that the contents of Cr and Ni and the infiltration temperature must be chosen appropriately in order to control the interfacial dissolution and reaction when the Cu-W alloys are prepared by the infiltration method.
关键词:
Wettability
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F. Wang
,
Z.K. Fan
,
J.F. Zhu
,
null
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null
,
null
金属学报(英文版)
In situ Al2O3 whiskers reinforced Ti-Al intermetallic composites were fabricated at ~1200℃ by reaction sintering of cold-consolidated fillets consisting mainly of Ti, Al, and different additives. The phases and microstructures of the sintered composites were characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (EDS). The process of synthesis was investigated using differential thermal analysis (DTA). The effects of processing parameters and additives on the microstructures of the composites and the development of whisker were examined. It is found that the morphology of the whisker is strongly influenced by the additives, the exothermal reaction process, and the processing parameters.
关键词:
in situ Al2O3 whisker
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