ZHENG Chaogui BAO Chenglin QIAO Zhiyu YE Yupu Peking University
,
Beijing
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China 1 University of Science and Technology Beijing
,
Beijing
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China Associate Professor
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Department of Chemistry
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Peking University
,
Beijing 100871
,
China
金属学报(英文版)
Five fields corresponding to the primary crystallization of PrCl_3,Sr_3PrCl_9,α(SrCl_2, CaCl_2),α_1(CaCl_2,SrCl_2)and α_2(SrCl_2,CaCl_2)respectively,six univariant lines related to the secondary crystallization,one ternary eutectic(48.0 wt-% PrCl_3,23.5 wt-% SrCl_2; 590℃)and ternary peritectic point(45.5 wt-% PrCl_3,24.5 wt-% SrCl_2;614℃) were determined by DTA.Attempts were also made to explore the rule governing the alteration in the phase diagram containing rare earth chloride,formation of compound and its stability by means of polarization and counter-polarization.
关键词:
PrCl_3
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ZHENG Chaogui LIU Hongping YE Yupu(Y.P.Yeh) Peking University
,
Beijing
,
ChinaQIAO Zhiyu University of Science and Technology Beijing
,
Beijing
,
China ZHENG Chaogui Dept.of Chemistry
,
Peking University
,
Beijing 100871
,
China
金属学报(英文版)
Three surfaces corresponding to the primary crystallization of PrCl_3,CaCl_2 and MgCl_2 respectively,3 univariant curves related to the secondary crystallization and a ternary eutectic(44.8 wt-% PrCl_3,31.8 wt-% CaCl_2,546℃)were found in system PrCl_3-CaCl_2-MgCl_2 by means of DTA.A reaction occurs in this system: L=PrCl_3+CaCl_2+MgCl_2.
关键词:
PrCl_3-CaCl_2-MgCl_2
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ZHANG Qiyun HAN Wanshu LIU Junkang Peking University
,
Beijing
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China ZHANG Qiyun Professor
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Dept.of Chemistry
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Peking University
,
Beijing 100871
,
China
金属学报(英文版)
The interaction between Cu and liquid Sn was studied by microstructure observation.The curve of the dipping time with related to dissolving and diffusion of Cu in liquid Sn is given. The Cu dissolves rapidly in liquid Sn at the beginning,then an intermetallic compound Cu_6Sn_5 forms,and the dissolving follows to slow down.At temperature up to 350℃,the hard feather-like Cu_6Sn_5 is sharply growing up and speads through the dipped Sn laver.The way to inhibit the growth of the intermetallic compound Cu_6Sn_5 was also approached.Thus,on the above mentioned basis,the physical meaning of the wetting curve traced by the meniscograph wettability tester has been derived as film detaching,Cu dissolying and Cu_6Sn_5 growing.
关键词:
Cu
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QIAO Lijie LIU Rui XIAO Jimei University of Science and Technology Beijing
,
Beijing
,
China
金属学报(英文版)
The effects of stress components on nucleation sites and propagation directions of stress cor- rosion cracks in brass were investigated with specimens under mode Ⅱ and mode Ⅲ loadings. The results indicated that under mode Ⅱ loading,stress corrosion cracks nucleated on the site with maximum normal stress component and propagated along the plane perpendieular to the maximum normal stress,under mode Ⅲ loading,the stress corrosion crack was not evident on the 45°plane due to the general corrosion in aqueous solution with high NH_4OH concentra- tion,while stress corroded in aqueous solution with low NH_4OH concentration, numerous cracks with spacings of 10—150μm were found on the 45°plane with maximum normal stress and no stress corrosion cracks was observed on the plane with maximum shear stress.
关键词:
stress corrosion cracking
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