钢铁钒钛

STUDY ON DYNAMICAL MECHANISM IN BLAST FURNACE RACEWAY

GUO Shu-yi, CHEN Ju-hua

2004, 25(3): 1-4,9.

Abstract(28) PDF(0)

Abstract:
Studying on the raceway mechanism can provide theory basis for the blast furnace operation. A cold state tridimensional model about raceway was built based on the similarity theory. Using tridimensional laser particle dynamic analyzer (PDA), the mean and pulsate velocity of gas and particle and other physical parameters in the model turbulent flow field were measured. It was found that the main velocity gradient changed rapidly in the vortex core. The experiments provided plentiful, referential and valuable data for the further study on the raceway mechanism.

INVESTIGATION IN LOW-TEMPERATURE COMBUSTION SYNTHESIS OF Fe-V-C SYSTEM UNDER ELECTRIC FIELD

LIN Hui-min, FENG Ke-qin, YANG Yi, HE Hong, SHEN Bao-luo

2004, 25(3): 5-9.

Abstract(24) PDF(0)

Abstract:
The effect of electric field on low-temperature synthesis of Fe-VC composites in the Fe-V-C system was investigated using Gleeble thermal simulation apparatus. Through analyzing the thermal characteristics of heating up period, a conclusion is obtained that the key reason which causes the diffusion of ion or atom of reactant under low temperature is the field emission. A series of research, such as the X-ray diffraction (XRD) analysis of product, the metallographic observation and scanning electron microscope (SEM), shows that the starting temperature of synthesis reaction is relative low (about 740 ℃) and the system react thoroughly with the effect of electric field. The synthesis reaction makes the sample become more compact, and the VC particles are small and distribute in the Fe base evenly.

NUMERICAL SIMULATION OF PLATE ROLLING PROCESS

ZHANG Qing-quan, LIU Yong-mou, YAO Jin

2004, 25(3): 10-16.

Abstract(19) PDF(0)

Abstract:
FEM numerical simulation is a useful tool to simulate the plate rolling process, it could help to extend the mill life, improve the quality of the plate and reduce the cost of trial-and-error processes. In this paper, some of the most concerned problems in numerical simulation of plate rolling process are analyzed and discussed using MSC marc software. The distribution of frictional force on the rolling plate surface and the effects of friction on rolling process are discussed. Different material hardening models such as isotropic hardening, kinematic hardening and combined hardening are investigated. The effects of thermal-mechanical couple on the plate rolling process and the numerical simulation method are presented.

EFFECT OF V-N MICROALLOYING ON HEAT TREATMENT CHARACTER OF Si-Mn SERIES SPRING STEEL

DONG Ya-jun

2004, 25(3): 17-20,29.

Abstract(24) PDF(0)

Abstract:
A series of experimental Si-Mn series spring steel which has different vanadium content was smelt in laboratory by Fe-V or VN alloying. The penetration hardenability, temper resistance, surface decarbonization and mechanical properties of the test steel were studied. The results show that the steel alloyed by VN alloy has good hardenability and temper resistance. The strength of steel increases with the increasing of vanadium content. There is no obvious effect on surface decarbonization use VN alloy compare with Fe-V alloy to smelt spring steel.

STUDY ON PROPERTIES OF NANO-TiO₂/POE/POPLYPROPYLENE COMPOSITES

DUAN Xiao-ping, HUANG Wan-xia, GUO Gang, CAO Jian-jun, TU Ming-jing

2004, 25(3): 21-25.

Abstract(17) PDF(0)

Abstract:
Nano-TiO₂/POE/PP composites were prepared via melt-blending process. The effects of nano-TiO₂ and POE on the rheological and mechanical properties were studied with rheometer, tensile tester and impact tester. And the affecting mechanism was studied. The results show that nano-TiO₂ improves the impact property obviously. Adding 4% nano-TiO₂ particles into composites can increase the impact strength strikingly, but over 4%, the impact strength will decrease due to particles gathering. Adding POE elastomer can improve the toughness of composite and the tensile strength only decrease slightly.

PREPARATION OF VO₂ POWDER AND ITS PHASE TRANSITION CHARACTERS

GUO Ning, XU Cai-ling, QIU Jia-wen, SU Zhong-xing

2004, 25(3): 26-29.

Abstract(19) PDF(0)

Abstract:
VO₂ powders were prepared by a new and simple method, which used VOSO₄ as raw material to form VO(OH)₂ sediment through hydrolysis process, then clean and dry the VO(OH)₂ sediment, VO₂ powders is produced by vacuum annealing process. XRD and XPS testing to the synthesized product show the VO₂ content in the samples approach 100%. The electrical and optical switching properties were tested, and the results show the resistance changed near two orders of magnitude and mid-IR transmissivity changed 15% because of the phase transition.

REVIEW OF PRODUCING BEARING STEEL BY BOF—BLOOM CONTINUOUS CASTING PROCESS

LI Jian, CHEN Tian-ming, YANG Su-bo

2004, 25(3): 30-35.

Abstract(24) PDF(0)

Abstract:
The production process of bearing steel, such as smelting, refining and continuous casting, was presented based on a lot of documents. The quality control was discussed as an emphasis. The main superiorities and the technical keys for producing bearing steel by BOF-bloom continuous casting process at PZH Steel were provided, and the way of development bearing steel was put forward.

LIGHT TREATMENT OF DEEP-DRAWING STEEL AT PZH STEEL

DENG Yun-yu

2004, 25(3): 36-40.

Abstract(14) PDF(0)

Abstract:
RH light treatment are used for some heats of molten steel refining at PZH Steel. According to the situation of molten steel and RH equipment, the refining practice includes pre-deoxidizing in steel tapping, carbonizing and adjusting the [C]/[O] ratio. An empirical formula was set up for carbonizing, and the practice proved it is effective. The hitting accuracy of RH light treatment is relative high, the final [C] qualification rate exceeds 90%, the final [C] qualification rate exceeds 95%, and the [O] is 30×10^-6～70×10^-6. The internal quality of deep-drawing steel after RH light treatment is satisfying.

RESEARCH OF PRODUCING HIGH SILICON B-LITE SULFUR ALUMINATE CEMENT BY TITANIUM TAILINGS

ZHANG Ju-song, SUI Zhi-tong, SHEN Yan-ming, HUI Zhi-feng, AN Hui-yong, GAO Fei

2004, 25(3): 41-47.

Abstract(14) PDF(0)

Abstract:
The authors analyzed the mineralogical composition of titanium tailings, and proposed a new view that applies titanium tailings, low-grade alumina and titanium-containing plaster to produce high silicon B-lite sulfur aluminate cement according to the feature of the cement. Moreover, they investigated systematically agglomeration temperature, cooling conditions, strength and setting time of the cement. The results show that the agglomeration temperature is low but the strength and setting time are situated in between silicate cement and rapid-hardening sulphoaluminate cement. It is to say that the high- titanium materials have no harm to high silicon B-lite sulfur aluminate cement.

ACTION MECHANISM OF HIGH TITANIUM BF SLAG IN CONCRETE

WANG Huai-bin, FAN Fu-zhong, HAO Jian-zhang, ZHANG Ji-dong, AO Jin-qing

2004, 25(3): 48-53.

Abstract(36) PDF(0)

Abstract:
The action mechanism of high titanium blast furnace (BF) slag in concrete was studied by XRD、 DTA、 SEM and determining the combine-water amount of hydration process. The results show that the high titanium blast furnace slag mixed in the concrete can help concrete to form microcosmic compact deposit, accelerate the hydration rate of cement, produce "the second reaction", advance the strength of concrete. "The second reaction" of high titanium blast furnace slag takes place at the later stage of hydration. When mix right amount of exciting agent in high titanium blast furnace slag, it can accelerate the "the second reaction" to progress.

DEVELOPMENT AND APPLICATION OF HIGH SPEED STEEL ROLL

ZHANG Hong-yue

2004, 25(3): 54-60.

Abstract(27) PDF(0)

Abstract:
High speed steel roll has the characteristics of high hardness, good red hardness and excellent wear-resistance, is widely used in steel rolling industry. The composition, microstructures and properties of high speed steel rolls are simply reviewed.The manufacture methods of high speed steel rolls are particularly discussed and the characteristics of different methods are commented. The service effects of high speed steel roll and the problems existing in the use of high speed steel roll are discussed, researching and developing direction of high speed steel roll is also forecasted.

RESEARCH PROGRESS IN PHOTOINDUCED SUPER HYDROPHILICITY OF TiO₂

LI Jing, TAN Xin, ZHAO Lin

2004, 25(3): 61-66.

Abstract(21) PDF(0)

Abstract:
TiO₂ is of good performance, such as chemical stability, high photocatalysis activity, and so on. The photo-induced super hydrophilicity of TiO₂ is a research focus lately. The photocatalysis mechanism of TiO₂ was presented in this paper. The effect of crystal configuration, external impurities, light and its intensity, semi-conductor dual composite on the photo-induced super hydrophilicity of TiO₂ was discussed. The industrial applications of TiO₂ were introduced.

DETERMINATION OF PHOSPHORUS IN V-N ALLOY

ZHENG Xiao-min

2004, 25(3): 67-70.

Abstract(17) PDF(0)

Abstract:
Trace phosphorus in V-N alloy was determined by beryllium salt coprecipitation—molybdenumblue spectrophotometry. This method was proved to have good precision and veracity. The low limit of determination is 0.001 6%, which completely satisfy the analytical request. The method is successfully applied to the determination of phosphorus in V-N alloy and the determining results are satisfying.

2004 Vol. 25, No. 3