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21.
In shape memory materials,that have been trained to have a two way shape memory effect(TWSM),themartensitic variants are classified into two groups,i.e.,preferentially oriented variants and self-accommodatingvariants.Applied stress may promote or constrain the transition of preferentially oriented variants and so changetransformation temperatures but has no essential effect on self-accommodating variants.According to the pointof view mentioned above,some experimental phenomena during thermocycling of a TWSM device may be ex-plained,such as the absence of synchronization between the plot of resistance change.temperature and the plotof memory strain vs.temperature. 相似文献
22.
The experimental researches on the chemical deposition of Ni-Mo-P amorphous alloys were carried out by adding Na2 MoO4 into acidic solutions. The optimum technology conditions were obtained by orthogonal design experiments. The structures and the relationship between compositions and their thermal stability were studied by energy spectrum (EC), scanning electron micrograph and X-ray diffraction spectrum. Compared with Ni-P amorphous alloys, the Ni-Mo-P amorphous alloys have high crystallization temperature and thermal stability, and the hardness reaches its peak when the annealing temperature is 500 ℃. With the increase of the heat treatment temperature, the surface morphology of the alloys changes. 相似文献
23.
THERMODYNAMICSANDPHASEEQUILIBRIUMOFCu-Y-O,Cu-Y-S,Cu-Y-O-SLIQUIDSOLUTIONS¥Du,Ting;Li,Guodong(CentralIronandSteelResearchinstit... 相似文献
24.
Y.?S.?HanEmail author J.?O.?Choi C.?O.?Choi D.?G.?McCartney 《Metals and Materials International》2004,10(1):27-32
The present study has been undertaken to better understand the solidification behavior of Al−Si−Fe alloys containing 7wt.%
Si and 0.9wt.% Fe, with particular regard to the formation of phase during controlled solidification and influence of growth
rates on intermetallic phase selection. The alloys studied were Al-7Si-0.9Fe alloys, which were produced by a modified Bridgman
solidification arrangement. These alloys were solidified unidirectionally with different growth rates (1–30mm/min). The solidified
microstructure of these alloys consists of the growth of primary aluminum and multiple second phase reactions. 相似文献
25.
26.
湿法相分离不对称超滤膜形成机理 总被引:1,自引:0,他引:1
本文选择了憎水的极怀非普质子性聚砜和亲水的极性质子怀聚砜酰胺两种膜材料,从铸膜液组成和凝胶过程两方面,用气相色谱和高效液相色谱研究了表征膜材料-溶剂-添加剂-水作用力的混合自由焓,平衡分配常数,及其与膜性能,不同溶剂特性粘度,雾点值和溶解度参数的关系,提出了铸膜液中有机溶剂的作用机理,及不对称超滤膜形成的一些规律。 相似文献
27.
对ITO粉样品用Rietveld全谱图拟合法进行了定量相分析,该样品由立方晶型的In2O3和少量的四方晶系的SnO2所组成。In2O3和SnO2质量百分含量分别为94.23%和5.77%。结果表明,用Rietveld法进行了定量相分析是非常有效和准确的。 相似文献
28.
Ki-Won Kim Pyeong-Seok Cho Jong-Heun Lee Seong-Hyeon Hong 《Journal of Electroceramics》2006,17(2-4):895-898
A new method for preparing SnO2 whiskers by the decomposition of SnC2O4 is suggested. A Whisker-like morphology of a SnC2O4 precipitate was attained via the gradual addition of an oxalic acid solution to a hot SnCl2 aqueous solution (T > 50∘C). In comparison, when the solution temperature was either lower than 50∘C or when ethanol was used as the solvent, the SnC2O4 precipitate showed an angular and relatively isotropic morphology. The morphology of the SnC2O4 precipitate remained even after its thermal decomposition into SnO2 at 400∘C indicating that SnC2O4 precipitation is a key step in preparing the whiskers. The formation mechanism of SnO2 whiskers was explained by the supersaturation during the precipitation of SnC2O4. 相似文献
29.
A. A. Kalachev N. M. Blashenkov Yu. P. Ivanov V. A. Marikhin A. L. Myasnikov L. P. Myasnikova 《Measurement Techniques》2005,48(8):773-778
A nanoluminescent device, or nanoluminograph, has been developed, created, and patented. By means of the device, unique information
about the physicochemical properties of surface and near-surface layers of solids and ultrathin coatings of thickness less
than 0.4 μm may be obtained. There is also the hope of decreasing the thickness of the subject layer with further development
of the detecting component of the device.
__________
Translated from Izmeritel'naya Tekhnika, No. 8, pp. 28–31, August, 2005. 相似文献
30.
文章介绍了三相异步电动机电源的相序接反,断相,三相电压不平衡的故障监测保护电路的电路结构及工作原理。 相似文献