LIU Miaoxiu CHENG Zhaonian CHEN Nianyi Shanghai Institute of Metallurgy
,
Academia Sinica
,
Shanghai
,
ChinaKE Jiajun Institute of Chemical Metallurgy
,
Academia Sinica
,
Beijing
,
China CHEN Nianyi
,
Professor
,
Shanghai Institute of Metallurgy
,
Academia Sinica
,
Shanghai 200050
,
China
金属学报(英文版)
The regularity of the carbonization process in alumina production has been summarized by the pattern recognition and regression.A mathematical model has been proposed to describe the factors affecting the silica content of aluminium hydroxide product.The high concentration of aluminate ions in solution will produce aluminium hydroxide with low content of SiO_2 under the condition of Al_2O_3/SiO_2 ratio kept unchanged.This was confirmed by certain scale experiments.
关键词:
carbonization
,
null
,
null
,
null
LIU Chunpeng XU Yousheng HUA Yixin Kunming Institute of Technology
,
Kunming
,
650093
,
China.
材料科学技术（英）
In applying the microwave radiation to extractive me- tallurgy,it is essential first of all to find the extent of microwave energy absorbed by various minerals experi- mentally.In this paper,more than 25 kinds of common useful minerals have been individually irradiated by a 500 W,2450 MHz microwave source in an enclosed quartz crucible to ascertain their heating temperature in a definite time.In addition,the reduction and cbloridization tests were also carried out on the titanomagnetite concentrate and pentlandite with microwave heating,respectively. These experiments indicate potential applications of util- izing microwave energy in extractive metallurgy.
关键词:
microwave radiation
,
null
,
null
,
null
李开明
,
李亚洲
,
冯维贵
,
林长
量子电子学报
doi:10.3969/j.issn.1007-5461.2007.05.014
采用非线性反馈控制,用附加了带参数的正弦项对Chen系统进行了有效的控制.随着参数k的逐渐增大,系统的动力学行为呈现出一系列的变化.数值研究结果表明:随控制参数的增大,驱动信号的强度渐大,混沌系统由混沌运动到周期轨道,最终到一相点.
关键词:
混沌
,
Chen系统
,
不动点
,
Lyapunov指数
,
反馈控制
Z. T. Ma and D. Janke(Institute of Iron and Steel Technology
,
Freiberg University of Mining and Technology
,
Germany)
金属学报(英文版)
Useder certain conditions, nonmctallic inclusions such as oxides, sulfides, nitrides and carbides are no longer harmful to sted service properties. With the new concept of oxide metallurgy, these properties can be improved by generating fine oxide inclusions which serve as heterogeneous nuclei for sulfide and fine ferrite[1-4]. A novel continuous casting (CC) process is expected to be created with the utilization of oxide metallurgy. This is also useful for the forthcoming technologies of direct rolling and near-net-shape casting. The main idea of oxide metallurgy consists of an alternative oxidation technology. It is based on steels treated by complex metals such as Ti, Zr, Ti-Zr alloys and rare earth metals. The selected deoxidants should follow the required conditions which are concluded in this paper.
关键词:
oxide
,
null
,
null
,
null
Yong LIU
,
Lifang CHEN
,
Weifeng WEI
,
Huiping TANG
,
Bin LIU
材料科学技术（英）
Ti-4.5Al-6.0Mo-1.5Fe, Ti-6Al-1Mo-1Fe and Ti-6Al-4V alloys were prepared by blended elemental powder metallurgy (PM) process, and the effects of Nd on the microstructures and mechanical properties were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). It was found out that the addition of Nd increased the density of sintered titanium alloys slightly by a maximum increment of 1% because small amount of liquid phase occurred during sintering. The addition of Nd shows little effect on the improvement of tensile strength, while the elongation is significantly improved. For example, the elongation of Ti-4.5Al-6.0Mo-1.5Fe can be increased from 1% without addition of Nd to 13% at a Nd content of 1.2 wt pct.
关键词:
Powder metallurgy titanium alloy
,
null
,
null
,
null
A.A.A. Saleh
,
Y. Fu
,
X.J. Zhai
金属学报(英文版)
Nano-ZnO particle was produced by evaporating zinc powders in air at air °ow-rate
from 0.2 to 0.6m3/h. Nano-ZnO particles was formed by the oxidation of the evapo-
rated zinc vapor. X-ray di®raction shows the powders to be ZnO with lattice parame-
ters of a=0.3249nm and c=0.5205nm. The particle size is dependent upon the transit
time from the source to the collection area. The size of particles was ranged between
81 to 103nm. The average density resulted was 4.865g/cm3.
Normal ZnO and nano-ZnO were investigated to use them in aluminum metallurgy as
an inert anode material. A certain amount of both oxides were molded subsequently
inserted to the molten cryolite-aluminum oxide to investigate the corrosive behavior
of both oxides. When the sintering temperature increased up to 1300±C, the weight
loss ratio rose to 5.01%{7.33% and up to 7.67%{10.18% for nano-ZnO and normal
ZnO, respectively. However, when the samples in the molten cryolite aluminum oxide
were put for long time, the corrosive rate was found to be higher. It was found that
the corrosive loss weight ratio of nano-ZnO anode was much lower than the normal
one made from ordinary-ZnO providing that the nano-ZnO is more possible to be use
inert anode material.
关键词:
reactive evaporation method
,
null
,
null
ZHOU Jiankun LIU Xianghuai CHEN Youshan WANG Xi ZHENG Zhihong HUANG Wei ZOU Shichang Shanghai Institute of Metallurgy
,
Academia Sinica
,
Shanghai
,
China
金属学报(英文版)
The TiN films were synthesized with an alternate process of depositing titanium from a E-gun evaporation source and 40 keV N~+ bombarding onto the target.It is shown from the composi- tion analysis and structure investigations using RBS,AES,TEM,XPS and X-ray diffraction spectrum that the formed fihns are mainly composed of TiN phase with grain size of 30—40 nm and without preferred orientation,the nitrogen content in the film is much less than that in case without N~+ bombarding,and an intermixed region about 40 nm thick exists between the film and the substrate.The films exhibt high microhardness and low friction. ZHOU Jiankun,Ion Beam Laboratory,Shanghai Institute of Metallurgy,Academia Sinica, Shanghai 200050,China
关键词:
TiN film
,
null
