QI Yunxin Nei Monggol Institute of Metallic Materials
,
Baotou
,
China QI Yunxin
,
Professor
,
P.O.Box No.4
,
Baotou 014034
,
Nei Monggol
,
China
金属学报(英文版)
The nitride in 30CrNi steel and its composition along boundaries have been studied by means of scanning Auger microprobe.The nitride identified metallographically is Zr(C,N)which contains a small amount of Ti and O.The interface width between the Zr(C,N)and the matrix is about 1.6 μm.An Fe-rich shell is.found on the surface of Zr(C,N)which appeared on the fracture surface.The thickness of shell is 0.1-0.8μm.The Fe concentration of its outmost layer is 3-18 at.-% and decreases exponentially along the depth direction.
关键词:
nitride
,
null
,
null
,
null
,
null
SHI Lin
,
LI Zhi-ling
,
YU Tao
,
LI Jiang-peng
钢铁研究学报(英文版)
In blast furnace (BF) iron-making process, the hot metal silicon content was usually used to measure the quality of hot metal and to reflect the thermal state of BF. Principal component analysis (PCA) and partial least-square (PLS) regression methods were used to predict the hot metal silicon content. Under the conditions of BF relatively stable situation, PCA and PLS regression models of hot metal silicon content utilizing data from Baotou Steel No6 BF were established, which provided the accuracy of 884% and 892%. PLS model used less variables and time than principal component analysis model, and it was simple to calculate. It is shown that the model gives good results and is helpful for practical production.
关键词:
hot metal silicon content
,
partial least square
,
principal component analysis
,
temperature prediction
WANG Yi-ci
,
ZHANG Jian-liang
,
ZHANG Fang
,
LUO Guo-ping
钢铁研究学报(英文版)
Influence of sintering temperature, basicity and MgO content on the formation characteristics of calcium ferrite in low silicon sinter of Baotou Iron and Steel Company was studied by means of mini-sintering test and mineralographic microscope analysis. In addition, the suitable sintering parameters such as temperature and basicity were explored. The results found that optimum temperature for the formation of calcium ferrite is 1280 ℃, the basicity of 25-28 is helpful to the development of acicular or columnar calcium ferrite, and MgO content in the low silicon sintering raw materials should be lower than 28% because MgO can intensively inhibit the formation of calcium ferrite. And calcium ferrite in the sinter belongs to calcium ferrite with low calcium, which is different from that in ordinary sinter at home and abroad. So, it provided theoretical basis for promoting formation of calcium ferrite in low silicon sinter and improving properties of sinter.
关键词:
low silicon sinter
,
formation characteristics
,
calcium ferrite
,
sintering temperature
,
basicity
ZHANG Fang
,
AN Sheng-li
,
LUO Guo-ping
,
WANG Yi-ci
钢铁研究学报(英文版)
Abstract: Baivumebo iron ore is special magnetite containing fluorine, kalium and sodium elements, and the main raw material for ironmaking of Baotou Iron and Steel (Group) Co. The effects of basicity and ratio of Al2O3 to SiO2 (A/S) on the formation of silico-ferrite of calcium and aluminium (SFCA) in Baivumebo low silica sinters were studied by means of mini-sintering, XPF-500 optical mineralogical microscope and CSS-88000 electronic universal testing machine. The results show that it is beneficial to the formation of complex calcium ferrite to enhance the basicity of Baivumebo low silica sinters. The acicular SFCA-I was increased with the enhancing basicity and reached the peak at basicity 28, then the columnar or platy SFCA formed and the bonding strength decreased. Alumina is beneficial to the formation of acicular complex calcium ferrite in Baivumebo low silica sinters. But the residual unfused Al2O3 reagent came into being when A/S was 035, while complex calcium ferrite still remained to be acicular. There is a common rule about mineralogy components affected by basicity and ratio of A/S, that is, SFCA is increasing accompanied with hematite and porosity reduced, but the content of glass phase is stable.
关键词:
Key words: Baivumebo iron concentrates
,
Baivumebo low silica sinter
,
SFCA
,
basicity
,
alumina-silica ratio
TIAN Hong-yu
,
CHEN Fu-rong
,
XIE Rui-jun
,
et al>
钢铁研究学报(英文版)
Hot-metal ladle is an important part in continuous casting production line and its stress distribution has direct influence on its life. In the process of design and calibration of the large sized hot-metal ladle, it’s of great significance to determine the stress distribution of each part of the ladle for safely and reliably running the device. Based on 100t hot-metal ladle which is designed by Baotou Iron & Steel Group, a simulation of stress field was made by finite element software ANSYS 10.0 in the different dumping angles. Through modeling, loading, restricting and calculating, strain and stress field distribution of the hot-metal ladle were acquired. Finally, an assessment of strength and stiffness was made on the hot-metal ladle. The results show that in the process of tipping for the hot-metal ladle, maximum stress is 137MPa, maximum strain is only 0.681‰, maximum stress and strain have appeared in the stiffener plate which is located at the bottom of the trunnion, and strength and stiffness are qualified. The method which is convenient and practical, reasonable and reliable provides theoretical evidence for checking analysis and further optimal design of the hot-metal ladle.
关键词:
hot-metal ladle;stress field;finite element analysis