S.S. Yan
,
J.X. Lou
,
L. Zhang
,
R.Z. Zhang
,
Y.M. Zhang
,
Y.H. Liu
,
L.M. Mei and J. Huang(Department of Physics
,
Shandong University
,
Jinan 250100
,
China)(Department of Environment Engineering
,
Shandong University
,
Jinan 250100
,
China)
金属学报(英文版)
Co/Cu discontinuons multilayers were prepared by rf-sputtering method under high sputtering power and then annealed at various temperutures in a high vacuum. The structural, magnetic and transport properties were strongly influenced by the annealing temperature. The annealed samples obviously became discontinuous multilayers.A maximum magnetoresistance ratio of 5.6% was obtained under a relatively low saturation field of about 400 (103/4π)A/m at the optimum annealing temperature of 450℃. When the annealing temperature was increased, the resistivity decreased, and the coercive force and the saturation field increased. The magnetoresistance ratio also depended on the thickness of Co and Cu layers. The magnetic and transport properties were explained on the basis of the discontinuous multilayered structure.
关键词:
discontinuous multilayers
,
null
,
null
Ruwei GAO
,
Yihua LIU
,
Shishen YAN Deheng ZHANG and Lin ZHANG(Dept. of Physics
,
Shandong University
,
Jinan 250100
,
China)
材料科学技术(英文)
Magnetism and its dependence on annealing temperature for r.f. sputtered Co/Cu multilayers have been investigated. It was found that the easy magnetization axes of the films are paralIel to the substrate and the magnetic properties of both as-sputtered and annealed multilayers are isotropic in the film plane. The coercive field Hc is 4.8 kA/m and the ratio of remanence-tosaturation magnetization Mi/M is about 0.73 for as-sputtered samples. Both Hc and Mr/Ms increase with increasing annealing temperatures, especially when annealing temperatures are higher than 400℃. These experimental results can be interpreted using the ferromagnetic exchange coupling and the pinning theory of the coercivity
关键词:
GAO Jin-tao
,
LI Shi-qi
,
ZHANG Yan-ting
,
ZHANG Yan-ling
,
CHEN Pei-yu
,
SHEN Ping
钢铁研究学报(英文版)
The process of “re-resourcing of converter slag” was put forward based on the analysis of the existing steel slag treatment process. The converter slag obtained from Jinan steel plant was studied. After grinding, the slag contained 33% of iron particles, 5484% of magnetic part (wTFe=20%), and 4184% of non-magnetic part, which could be used for making cement directly. At a temperature below 1000 ℃, the non-magnetic Fe2O3 in the slag could be efficiently reduced to magnetic iron by pure H2 and CO. The slag after precise reduction had high degree of dispersion and did not get sintered, which provided an optimum condition for the separation of iron and impurities. To separate the slag and enrich the iron after reduction, the laboratory-scale device of magnetic separation was designed and made. The process of slag re-resourcing, which included magnetic sorting, precise reduction, magnetic separation, and removal of free calcium oxide (f-CaO), was proposed to obtain iron-rich magnetic materials and cement adulterant materials. Through this process, 33 kg iron particles, 150 kg iron-rich material and 700 kg cement could be obtained in each ton slag. Besides, this process to recycle converter slag had a lower energy and material consumption and no pollutant emission.
关键词:
converter slag
,
resource recycling
,
precise reduction
,
cement