Jian XU Xiukui SUN Wenxiu CHEN Wenduo WEI State Key Laboratory of RSA
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Institute of Metal Research
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Academia Sinica
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Shenyang 110015
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China
材料科学技术（英文）
In present work.the ultrafine manganese particles were prepared by gas evaporation method.The structure,size distribution,growth morphology and surface oxidation for the particles were investi- gated by using X-ray diffraction and electron microscopy.The results indicated that three types of the particles,with the structure of α-Mn,β-Mn and one unknown,respectively existed in the man- ganese particles.The growth morphology of the particles depended on the size and intrinsic structure.When exposed to air,the particles were slightly oxidized only in the surface layer and sta- ble in air.
关键词:
ultrafine particle
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null
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null
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null
陈祖耀
,
陈波
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钱逸泰
,
张曼维
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杨丽
,
范成高
金属学报
利用Co源强γ射线辐照制备金属超微粒子,并首次采用γ射线辐照—水热结晶联合法获得了Cu,Au和Cu—Au合金超细粉末,还初步讨论了超细粉的成核过程和考察了它们的形貌、晶粒大小以及稳定性。
关键词:
辐射化学
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hydrothermal crystallization
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ultrafine particle
WANG Shuhe CAI Yuling AN Gang WEN Lishi ZHUANG Yuzhi Institute of Metal Research
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Academia Sinica
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Shenyang
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China WANG Shuhe
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Associate Professor
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Institute of Metal Research
,
Academia Sinica
,
Shenyang 110015
,
China
金属学报(英文版)
The constitution,structure and surface state of the ultrafine iron particles prepared by gas evaporation technique have been investigated by means of X-ray analysis,high-reasolution electron microscopy(HREM)and electron spectroscopy for chemical analysis(ESCA).The results showed that the fine particles are spherical ones of～20 nm in diameter with α-Fe cores and covered by Fe_3O_4 fine crystalline layers of～4 nm thickness.
关键词:
ultrafine particle
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null
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null
ZHANG Yanzhong
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NIAN Suzhen Shanghai Iron and Steel Research Institute
金属学报(英文版)
Three new Fe-based microcrystalline alloys,i.e.,Fe_(73.1)Cu_(1.2)Nb_(3.2)Si_(12 5)B_(10), Fe_(73)Cu_1Nb_(1.5)Mo_2Si_(12.5)B_(10) and Fe_(73)Cu_1Zr_3C_(0.5)Mo_Si_(12.5)B_(10),were developed with su- perior magnetic properties.e.g.,high relative initial permeability of μ_i~15×10~4,low coercivity of H_c1.0A/m,high effective permeability and low core losses in a consid- crable wide frequency range and high pulse-magnetic permeability under narrow pulse. The optimum value of relative effective permeability,μ_5~1 is 16×10~4 under condition of f=1 kHz and H_m=0.4 A/m.The optimum values of core loss reach 57.9 30.2 and 68 W/kg under condition of f=50.100.100 KHz and B_m=0.5,0.2,0.3 T,respectively. These three alloys have superior stability of magnetic properties.Initial permeability may be not changed during heating at 130℃ up to 216 h.The main crystalline phase is ordered phase Fe_((75)+y)Si_((25)-y) which is ultrafine particles of average size 10—20 nm.
关键词:
microcrystalline alloy
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null
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null
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null
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null
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null
王晓慧
,
王子忱
,
李熙
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张丽华
,
肖良质
材料研究学报
用胶溶法合成了TiO_2超微粒子。研究了反应物浓度、胶溶剂用量、胶溶温度对胶溶过程的影响,以及表面活性剂DBS 的量与Ti 萃取率的关系。探讨了合成超微粒子TiO_2的最佳条件,分析了产品的特性。200℃热处理得到的产品为非晶型圆球状,粒度均匀,平均6.0nm,在许多有机溶剂中具有良好的分散性和透明性。550℃得到晶态锐钛矿型超微粒子TiO_2,粒度为8.5nm。700℃热处理得到金红石型TiO_2,粒度为33.2nm。
关键词:
超微粒子
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TiO_2
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colloidal chemical method
