2004 Vol. 25, No. 1

Display Method:
KEY TECHNOLOGIES FOR BLOOM CONTINUOUS CASTING AND ITS APPLICATION
CHEN Yong, LI Gui-jun, YANG Su-bo, WENG Jian-jun, CHEN Lu-ying
2004, 25(1): 1-6.
Abstract(16) PDF(0)
Abstract:
The key technologies, such as M-EMS, secondary cooling scheme, dynamic soft reduction, and its application to bloom continuous casting for heavy rail steel were presented. The operation shows that the defect-free blooms achieve 100% of total blooms produced from CC, center looseness and central segregation are ≤1.0, while, central shrinkage cavity is ≤0.5, central segregation index of carbon is ≤1.05, and the ratio of equiaxed zone is ≥38%. The qualified blooms are delivered to produce rail for high-speed tracks.
DEVELOPMENT OF DX54D GRADE SKIN-PASSED HOT DIP GALVANIZED Nb-Ti-IF STEEL SHEET
ZHENG Zhi-wang
2004, 25(1): 7-12.
Abstract(27) PDF(1)
Abstract:
The effect of Nb addition on the microstructure and mechanical properties of Ti-IF steel was discussed according to the facilities of the continuous hot-dip galvanizing line at PZH Steel, as well as the influence of annealing temperature and skin-passed reduction on extra deep drawing skin-passed hot-dip IF steel sheet. The grain refinement of Nb is applied to control the balance of n and r-value of the sheets, and DX54D grade skin-passed hot dip galvanized sheet with excellent mechanical properties has been developed according to DIN EN 10142 standard. This product is widely used to make panel of air conditioner as a substitute of deep drawing electrogalvanizing steel sheet.
CHEMICAL KINETICS OF PREPARING VN FROM REDUCING AND NITRIDING V2O5
XU Xian-feng, WANG Xi-tang
2004, 25(1): 13-18.
Abstract(25) PDF(0)
Abstract:
The reaction kinetics of preparing VN from reducing and nitriding V2O5 by solid carbon was discussed. On the base of thermal gravimetric analysis under high pure nitrogen and argon atmosphere respectively, the activation energy and frequency factor of reduction and nitrdiation are got by regression analysis of experimental data. The experiential formula of velocity constant and temperature of each reaction are obtained.
THERMAL AND MECHANICAL SIMULATION INVESTIGATION IN UPSET DEFORMATION OF RAIL BUTT WELDING
YAN Jun-qiang, DAI Hong, CHE Xiao-li, LÜ Qi-bing
2004, 25(1): 19-24.
Abstract(15) PDF(0)
Abstract:
The upset formation process of rail (U71Mn) butt welding was test by thermal and mechanical simulation using Gleeble-2000 simulator. The upset pressure of rail is studied with different heat-condition.The influence of upset length, speed and current time on the weld quality is investigated.The results provide scientific foundations for settling welding procedure and improving the weld quality of rail.
STUDY ON STATIC RECRYSTALLIZATION DEVELOPMENT AND MODEL IN HOT ROLLED Nb-Ti STEEL
YU Chi-bin, YE Chuan-long, ZHAO Gang, ZHANG Yun-xiang, SONG Ping, SU Yi, CHEN Liang, CENG Ping
2004, 25(1): 25-29.
Abstract(33) PDF(1)
Abstract:
The microstructure development of hot rolled Nb-Ti micro-alloying steel was discussed based on the hot state model test. The affect factors of microstructure development were presented. A mathematical model about static recrystallization and microstructure development was founded. The hot state model tests show the prediction results are in agreement with the experiment results. The study method could simulate the static recrystallization behaviors.
SIMULATION TEST ON FLOW PATTERN OF MOLTEN STEEL IN MULTI-STRAND TUNDISH
SU Zhen-jiang, WEN Guang-hua, TANG Ping, QI Xin, GU Wu-an, ZHAO Ke-wen, SONG Guo-ju
2004, 25(1): 30-33,50.
Abstract(24) PDF(0)
Abstract:
The flow pattern of molten steel in tundish of the 6-strand bloom caster at PZH Steel were investigated by physical simulation with isothermal and non-isothermal model.The results show that the natural convection has an important effect on the fluid flow in continuous casting tundish, so a non-isothermal water model should be employed when study the fluid flow pattern in big volume tundish. The experiments show the flow control device is necessary in tundish with the non-isothermal model.
ANALYSIS FOR CAUSE OF CRACKS IN HAZ OF X52 ERW PIPELINE
YU Teng-yi
2004, 25(1): 34-38,43.
Abstract(11) PDF(0)
Abstract:
Adopting metalloscope and SEM to inspect the fracture and inclusions in the cracks of X52 experimental-welded-pipe steel,the composition of the inclusions was analyzed.The results show that the mass dense RE-sulphide and RE-sulphide-oxide laminated zonal inclusions are the main causes of the cracks. With high temperature and welding pressure,the severance of inclusions forms crack.
DISCUSSION ON PRODUCTION OF VANADIUM-MICROALLOYING STEEL IN CSP LINE
JIANG Chang-lin, ZHU Tao, PAN Guo-ping
2004, 25(1): 39-43.
Abstract(17) PDF(0)
Abstract:
The strengthening and toughing mechanism of vanadium-microalloying steel and the technological trait of CSP line are reviewed.The feasibility of applying vanadium-microalloying in CSP line and some noticeable problems are discussed.The technological trait of controlled rolling and accelerated cooling for vanadium-microalloying steel is the integration of RCR and AC,and it is regarded as the characteristic and advantage of CSP line.
RECENT ACHIEVEMENTS IN PREPARING TECHNOLOGY OF SYNTHETIC RUTILE
DENG Guo-zhu, HUANG Bei-wei, WANG Xue-fei
2004, 25(1): 44-50.
Abstract(22) PDF(0)
Abstract:
An outline of synthetic rutile production is given. The recent achievements in preparing of synthetic rutile are reviewed. These achievements include some improvements on existing processes and new processes. The existing processes contain reduction-rusting process and week reduction-hydrochloric acid pressure leaching process. The improved processes contain improved reduction-rusting process, week reduction-hydrochloric acid fluid bed leaching process and week oxidization-hydrochloric acid pressure leaching process. The new processes contain one step chlorination process and titania slag-hydrochloric acid pressure leaching process.
FEASIBLITY DISCUSSION ON TYRE CORD STEEL PRODUCTION BY BLOOM CONTINUOUS CASTING PROCESS AT PZH STEEL
HUANG Yu-ming
2004, 25(1): 51-56,61.
Abstract(14) PDF(0)
Abstract:
The production process of tyre cord steel was presented, and the technical status quo of smelting, refining and continuous casting of tyre cord steel were analyzed by investigation technical data. The quality control means were suggested. The superiorities and technological keys for producing tyre cord steel at PZH Steel were discussed. The developing way of tyre cord steel was put forward.
STUDY ON PHOTODEGRADATION CAPABILITY OF ANATASE NANOMETER TiO2 FOR HCHO
DU Jian-qiao, WANG Lan-wu, QIU Fa-li, LU
2004, 25(1): 57-61.
Abstract(17) PDF(0)
Abstract:
The mechanisms of nanometer TiO2 photodegrading HCHO were summarized. The discussion focuses upon the influence of nanometer TiO2 content, crystal dimension, crystal type in the emulsoid and reaction temperature on the property of nanometer TiO2 photodegrading HCHO. The influence of HCHO molar consistency and degradation-reaction time on the photodegradation rate of HCHO are discussed.
STRAIN TEST AND NUMERICAL SIMULATION OF BOXY PART
CHEN Wen-long, QIU Xiao-gang, LU Guo-qing
2004, 25(1): 62-65,70.
Abstract:
The strain of a boxy part (the fuel tank of truck) was tested. The deformation was simulated by numerical simulation using the Dynaform software. By contrasting the test and simulation results, the influence of steel plate properties and deformation parameters on the forming of part was discussed. The reliable deformation parameters and steel plate properties(n≥0.23, r≥2.0) are gained.
DETERMINATION OF SULFUR IN V2O3 BY COMBUSTION IODOMATRIC METHOD
YI Gui-hua, PENG Li-ping, LI Ji-chun
2004, 25(1): 66-70.
Abstract(22) PDF(0)
Abstract:
In order to determining the sulfur content in V2O3 and solving the problems of no method and no standard sample, vanadium slag standard sample which has similar sulfur and same base with V2O3 was selected to as the content pass standard after a series of tests. Combustion iodomatric method is defined as the analytical method when determining the sulfur content of V2O3.