Solderabilities of electrodeposited Fe-Ni alloys with SnAgCu solder were examined by wetting balance measurements and compared to those of pure Ni and pure Fe platings. Excellent solderability was found on the Ni-52Fe...Solderabilities of electrodeposited Fe-Ni alloys with SnAgCu solder were examined by wetting balance measurements and compared to those of pure Ni and pure Fe platings. Excellent solderability was found on the Ni-52Fe plating as both the wetting force and kinetics approached or exceeded those on the pure Ni. However, upon further increase in Fe content to 75 at. pct, the solderability of the alloy was severely degraded even though it was still better than that of the pure Fe plating. X-ray photoelectron spectroscopy showed that such a strong dependence of solderability on Fe content is related to the much thinner, incomplete oxide coverage of Ni-rich plating surface.展开更多
Wetting of microporous Cu layer by liquid Sn resulted in contact angles from 0 to 33 deg., tunable by varying wetting temperature and porous microstructure. The wetting was dominated by the interracial metallurgical r...Wetting of microporous Cu layer by liquid Sn resulted in contact angles from 0 to 33 deg., tunable by varying wetting temperature and porous microstructure. The wetting was dominated by the interracial metallurgical reaction, which can lead to pore closure phenomenon, as the liquid infiltration facilitating the wetting process.展开更多
TiO 2 nanowires were synthesized successfully in a large quantity by thermal evaporation using titanium monoxide powder as precursor. X-ray diffraction results showed that all the products were pure rutile phase of Ti...TiO 2 nanowires were synthesized successfully in a large quantity by thermal evaporation using titanium monoxide powder as precursor. X-ray diffraction results showed that all the products were pure rutile phase of TiO 2 . According to microstructural observations, the nanowires have two typical morphologies, a long straight type and a short tortuous type. The straight nanowires were obtained at a wide temperature range of 900–1050 ℃, while the tortuous ones were formed below 900 ℃. Transmission electron microscopy characterization revealed that both the straight and the tortuous nanowires are single-crystal rutile TiO 2 . The preferential growth direction of the nanowires was determined as [110] orientation according to electron diffraction and high-resolution image analyses. The morphological change of TiO 2 nanowires was discussed by considering the different atomic diffusion rates of Ti atoms caused by the phase transformation in Ti substrate at around 900 ℃.展开更多
文摘Solderabilities of electrodeposited Fe-Ni alloys with SnAgCu solder were examined by wetting balance measurements and compared to those of pure Ni and pure Fe platings. Excellent solderability was found on the Ni-52Fe plating as both the wetting force and kinetics approached or exceeded those on the pure Ni. However, upon further increase in Fe content to 75 at. pct, the solderability of the alloy was severely degraded even though it was still better than that of the pure Fe plating. X-ray photoelectron spectroscopy showed that such a strong dependence of solderability on Fe content is related to the much thinner, incomplete oxide coverage of Ni-rich plating surface.
基金supported by the National Natural Science Foundation of China (Grant No. 50501022)the National Basic Research Program of China (Grant No.2010CB631006)
文摘Wetting of microporous Cu layer by liquid Sn resulted in contact angles from 0 to 33 deg., tunable by varying wetting temperature and porous microstructure. The wetting was dominated by the interracial metallurgical reaction, which can lead to pore closure phenomenon, as the liquid infiltration facilitating the wetting process.
基金supported by the Hundred Talents Program of the Chinese Academy of Sciences,Shenyang Science and Technology Project (Grant No.F11-264-1-65)the National Basic Research Program of China (Grant No. 2010CB631006)the Major National Science and Technology Program of China (GrantNo. 2011ZX02602)
文摘TiO 2 nanowires were synthesized successfully in a large quantity by thermal evaporation using titanium monoxide powder as precursor. X-ray diffraction results showed that all the products were pure rutile phase of TiO 2 . According to microstructural observations, the nanowires have two typical morphologies, a long straight type and a short tortuous type. The straight nanowires were obtained at a wide temperature range of 900–1050 ℃, while the tortuous ones were formed below 900 ℃. Transmission electron microscopy characterization revealed that both the straight and the tortuous nanowires are single-crystal rutile TiO 2 . The preferential growth direction of the nanowires was determined as [110] orientation according to electron diffraction and high-resolution image analyses. The morphological change of TiO 2 nanowires was discussed by considering the different atomic diffusion rates of Ti atoms caused by the phase transformation in Ti substrate at around 900 ℃.
