- Email: [email protected]
Abstracts—From Journal of Iron and Steel Research (in Chinese)
Vol. 14
No. 3
Journal of Iron and Steel Research, International
May 2007
ABSTRACTSFrom Journal of Iron and Steel Research (in Chinese)
Technological Situation of Steel Wire for Steel Cord of Radial Tire Z H A NG X i , W A N G Chun-xu2 , S H I Qing-nunJ ( 1 . Faculty o f Materitals and Metallurgical Engineering, Kunming University o f Science and Technology, Kunming 650093, China; 2. Institute for Structural Materials, Central Iron and Steel Research Institute, Beijing 100081 , China) Abstract: According to the need for lightening of cars, requirement on strength of steel cord for radial tire is steadily increased. At present, 4 000 MPa level steel cord for radial tire is commercialized and becomes the strongest industrial material. The culminated strength of steel cord for radial tire, strengthening method, strengthening mechanism, structural change in drawing process, technology of microstructure control and technology for improving ductility through secondary processing are introduced. Key words: radial tire; steel wire; steel cord; technological progress [cf. 2007,19(1):1]
Some Aspects of Electromagnetic Continuous Casting Process With Soft-Contact Mold LEI Zuo-sheng , REN Zhong-ming , L I Wei-xuan , DENG Kang ( Shanghai Enhanced Laboratory o f Ferro-Metallurgy , Shanghai University, Shanghai 200072, China) Abstract:The development of electromagnetic continuous casting process with soft-contact mold was reviewed from four aspects: the distribution of electromagnetic field in the mold and the design of the mold, the mechanism of improving the surface qualities and meniscus behavior in electromagnetic field and the electromagnetic field type' s development in the process. The remarhable were pointed out. Key words: continuousfa casting; electromagnetic continuous casting; soft-contact mold [cf. 2007,19(1) :S]
Simulative Research on Coke Strength in Lumpish Section of Blast Furnace F A N G J u e , W A N G Xing-juan, GONG Rui-juan, R E N Rong-xia (College of Metallurgy and Energ y , Hebei Polytechnic University, Tangshan 063009, Hebei, China) Abstract: The relationship between temperature, carbon loss
rate and compression strength of coke in the lumpish section of blast furnace was investigated. A simulative research on the lumpish section in a blast furnace was completed using a hot model. The compression strength of the coke samples was measured using a compression testing machine with adjustable atmosphere at practical temperatures. The distribution of coke strength after reaction was obtained. In the indirect reduction section of blast furnace, the relationship between compression strength of coke and temperature is linear. In the lower section, the strength decreases rapidly with the rising of the temperature. The carbon loss rate of coke is the main factor affecting its strength. In the condition with high coal rate, coals with good reactivity and a suitable combustion ratio should be used to protect the coke strength. Key words: coke; practical temperature; compression strength; carbon loss rate; blast furnace [cf. 2007,19(1) :12]
Mathematical Model for Description of Liquid Momentum Transport Within Packed Bed Existing Inside Blast Furnace W A N G Cheng-shun' , Z H E N G Shao-bo2 , J I A N G Guo-chang' , X I A O Xing-guo3 , W A N G Wenzhong ( 1 . College o f Materials Science and Engineering, Chongqing University , Chongqing 400044, China; 2. State Enhance Laboratory of Ferro-metallurgy , Shanghai University , Shanghai 200072 , China ; 3 . School o f Materials and Metall u r g y , Northeastern University, Shenyang 110004 , Liaoning , China) Abstract: With regard to the existent mathematical model describing the liquid momentum transport within the packed bed utilized in iron-making process, there are some obstacles in engineering design, or some severe limitations in mathematical descriptions. In this paper, the effects on the liquid flow of the packed bed were divided into two parts: resistance action and dispersal action, and appropriate mathematical descriptions were given to the two actions respectively. Consequently, a new mathematical model of describing liquid flow inside packed bed was built, The results show that the model presented here could simulate the iron-making process such as blast furnace process much more appropriately. Key words: mathematical model; liquid flow; packed bed; ironmaking process [ ~ f2007,19(1):16] .
Abstracts from Journal of lron and Steel Research (in Chinese)
*I[*
Continuous Casting Technology of Mn-Si Ferrous AlIOY
W A N G Mei' , Z H A O Zongg e n g ' , Z E N G S h i - l i n 3 , LIANG Jian-qiang3, LU Bing ( 1 . National Engineering Research Center of Continuous Casting Technology Central Iron and Steel Research Institute, Beijing 100081 , China ; 2 . School of Materials Science and Engineeri n g , Hebei University of Science and Technology , Shijiazhuang 050054 , Hebei, China; 3 . Department of Science and Technology , Guangxi Bayi Ferrous A l l o y Ltd , Liuzhou 54610 2 , Guangxi, China)
YAO Shu-fang'
,
Abstract:The techniques and the internal and external qualities of continuous cast Mn-Si ferrous alloy which had been cast on a set of continuous cast experiment equipment with a special mould were studied. Some Mn-Si ferrous alloy ingots with diameter of 44, 52, 54 and 74 mm respectively were steadily continuously cast. The results show that the stability of MnSi alloy continuous cast techniques is good, the surface of MnSi alloy continuous cast ingot is smooth, the microstructure of Mn-Si alloy continuous cast ingot is fine and dense, and the quality of Mn-Si alloy continuous cast ingot is superior to that of mould cast ingot. Key words: Mn-Si; Ferrous alloy; continuous casting: mould casting
[ ~ f2007,19(1) . :22]
FEM Analysis of Influence of Vertical Roll Shape on Head and Tail Shape of Rolled Piece During Multipass V-H Rolling Process W Hai-liang' , LIU Xiang-hua' , Z H A O Xianming' , S I Liang-ying' , N I U Hai-shun' , Kusaba Y 2( 1 . The State K e y Laboratory of Rolling and Automation , Northeastern University , Shenyang 11.0004, Liaoning, China: 2. Sumitomo Metal Industries, Ltd J a p a n , 6000891 , J a p a n ) Abstract: The multipass V-H rolling process with different vertical roll shape was simutated by explicit dynamic FEM and updating geometric method, and the head and tail shape of rolled piece for different pass and vertical roll shape was analyzed. The results show that when using flat vertical roll, the wedge angle appears in tail, but it does not appear when using shape vertical roll, and the length of rolled piece is shorter than that using shape vertical roll, so its elongation is larger; when using shape vertical roll, the head and tail shape of rolled piece changs little as the groove fillet radius of roll changes. At the same time, the calculated head and tail shape of rolled piece for flat vertical roll in different pass is consistent with the measured one when the model material is lead. Key words: V-H rolling; head and tail shape8 FEM; updating geometric method [ ~ f2007,19(1):26] .
Vol. 14
Simulation Analysis of Residual Stress in Oil Casing Pipe During Sizing Rolling LI L i a n - j i n ' * z , W A N G Hui-bin2 ( 1 . College of Mechanical Engineering, Tianjin University of Commerce, Tianjin 300134 , China ; 2 . Technical Center, Tianjin Pipe Corporation Ltd , Tianjin 300301, China) Abstract: In order to eliminate the size and roundness tolerance after the rolling and heat treatment of oil casing pipe, the straightening process should be used. The sizing process, the last procedure of producing oil casing pipe, plays a key role not only in controlling the size and geometry shape of the oil casing pipe, but also in affecting the mechanical performance. Therefore, in arder to meet the size and roundness tolerance requirement of the oil casing pipe, an investigation into the relationship between the sizing reduction and residual stress and an analysis of sizing deformation process of the oil casing pipe are carried out. The goal is to reduce the residual stress of sizing process, achieve an ideal sizing result. enhance the mechanical performance of the oil casing pipe and provide a theoretical basis for making the sizing process. Key words: oil casing pipe; sizing; residual stress; carrying capacity [ ~ f2007,19(1):31] .
Thermodynamics of Carbide and Nitride Precipitation in HSLA Steel YUE Er-bin"Z, QIU Sheng-tao''2 , G A N Yong' ( I. State K e y Laboratory o f Advanced Steel Processing and Products, Beijing 100081 , China; 2. National Engineering Research Center of Continuous Casting Technology, Central Iron and Steel Research Institute, Beijing 100081 , China)
Abstract: The thermodynamics conditions of formation of carbides and nitrides in HSLA steel (16Mn steel) liquid, semisolid and solid austenite have been studied systematically. As a result, the precipitation equilibrium concentration of some related carbides and nitrides at different temperature is calculated and the precipitation sequence at different temperatures is obtained. Key words: HSLA; carbonnitrides; precipitation; thermodynamics [cf. 2007,19(1) :35]
Bauschinger Effect of Microalloyed Steel for Cold Heading Bolt in Cold Drawing Process M A Xiao-ping'", HUI Wei-jun' ? LIU Chunm i n g 2 , YU Tong-ren3 , SUN W e i 3( 1 . Institute of Structural Materials, Central Iron and Steel Research Institute, Beijing f 00081 , China ; 2 . School of Materials and Metallurgy ? Northeastern University, Shenyang 110004 , Liaoning , China ; 3. Technology Center uf Ma'anshan Iron and Steel Co
No. 3
Journal of Iron and Steel Research, International
*III*
L t d , Ma'anshan 243000, A n h u i , China)
versity, Shanghai 200072, China)
Abstract:In order to lower the flow stress in the cold heading process, the Bauschinger effect of microalloyed steel MFT8 for cold heading bolt was studied. The result shows that the Bauschinger effect increases with increasing cold-drawing reduction y. When y reaches 3 0 % - the Bauschinger effect is most significant, while the compression flow stress has a minimum value and the compression flow stress arises again when y is higher than 30%. This result is attributed to the interaction of Bauschinger effect and work hardening, that is to say, work hardening counteracts the Bauschinger effect. Key words: Bauschinger effect; cold deformation; cold hardening;microalloyed steel [ ~ f2007,19(1):39] .
Abstract: The chemical compositions of Nb-Ti and Nb-V microalloyed steels with tensile strength higher than 650 MPa are designed. The orthogonal test design method is used to investigate the effect of heating temperature, finish rolling temperature and finish cooling temperature on the mechanical properties of the two test steels. The experimental results show that the most important parameter affecting mechanical properties of the Nb-Ti and Nb-V microalloyed steels is heating temperature and finish cooling temperature respectively. The regression formulas describing the relations between A and Re and R,/R, and Re of the two steels are deduced. Key words: microalloyed steel; hot rolling temperature parameter; mechanical property [cf. 2007,19(1):48]
Solidification Segregation of Continuous Cast Steel Billets and Structure Heredity of High Strength Hot Rolled Rods H U A N G Z h e n - y i ' * 2 * 4C, H E N Guang' , N I U Yaran' , W A N G G ~ a n g - p e n g ~H ' ~U,A N G Y i - x i n 3 , L I U Wen-sue3( 1 Department o f Material Science and Engineering, Nanjing University o f Science and Technology, Nanjing 210094, Jiangsu, China; 2 . School o f Material Science and Engineeri n g , Anhui University o f Technology, Ma'anshan , 243002 , Anhui , China ; 3. Technological Center, Nanjing Iron and Steel Group Co L t d , Nanjing 210035, J i a n g s u , China; 4 . The K e y Lab o f Material and Processing, Anhui University of Technology, Ma'anshan 243002, A n h u i , China)
.
Abstract: The relationship between the element segregation of high carbon and high strength hot rolled rods and solidification structure is studied by SEM observation and chemical analysis. The results show that the formation of segregation band is mainly caused by serious segregation of C and Mn the segregation band is not sorbitic structure and has high strength and low plasticity. There are microcrack and microhole in them. The radical cause is serious segregation of continuous cast steel billets. The hot rods inherit segregation of continuous cast steel billets directly and the segregation greatly influences structure and property of hot rolled rods. According to heredity of segregation of continuous cast steel billets, effective measures have been taken against segregation. Key words: hot rod; segregation; continuous cast steel billet; heredity [ c f . 2007,19(1) :44]
Effect of Hot Rolling Parameters on Mechanical Properties of Nb-Ti and Nb-V Microalloyed Steels QlU Yu-bin' , L I N Da-wei' , H A N An-chang' ( 1 . Manu facture Department, Baoshan Iron and Steel , Shanghai 201900, China; 2. Materials Science and Engineering Institute, Shanghai Uni-
Co Ltd
Corrosion of Low-Carbon Nb Microalloyed Steel in Seawater W A N G Shu-lan, YANG Hui , Z H U A N G Li-jun (School o f Science, Northeastern University, Shenyang 11 0004 , Liaoning , China) Abstract: Niobium is one of the most effective microalloying elements of steel and has been used in niobium bearing steel for the construction of large ships and sea engineering. The corrosion behavior of niobium bearing steel in sea water is therefore very important. In this work, A. C. impedance spectra and corrosion potential of low-carbon Nb microalloyed steels at different corrosion stages were measured systematically, the charge transfer resistances of corrosion process were obtained and the charge transfer resistances increased with increasing the corrosion period. The results show that the corrosion resistance of the low-carbon Nb microalloyed steel is better than that of the niobium-free steel. Key words: Nb microalloyed steel; corrosion; impedance; charge transfer resistance [cf. 2007,19(1):53]
Preparatory Study on Optimal Control of Electro-Hydraulic Fatigue Testing Machine Z H A N G Fu-bo , W A N G Guo-dong , Z H A N G Dianh u a , L I U Xiang-hua ( S t a t e K e y Laboratory o f Rolling and Automation , Northeastern University, Shenyang 110004 , Liaoning , China) Abstract: Concerning the bad control effect for fatigue testing machine caused by variations of system parameters such as sample rigidity, oil temperature, interior leakage and so on, a method that can optimize the controller parameters on-line is brought forward. Based on the process parameters on-line identified by monitor computer, the PID parameters are optimized using the method of minimizing the objective function known as ITAE, thus the controller parameters suited for the current operating mode are obtained. This process is run at intervals of ten minutes automatically in monitor computer, and then the optimized PID parameters are transferred to controller through bus for real time control. Compared with the
*Iv*
Abstracts from Journal of Iron and Steel Research (in Chinese)
traditional method of tuning PID parameters according to experience, this method is simpler and improves the frequency response of the system. Key words: electrohydraulic servo control; fatigue testing machine; PID control1er;optimal control [cf. 2007,19(1):57]
A Simulation Software for Forecasting Finish Rolling Temperature for Hot Strip Mill GONG Dian-yao, X U J i a n - z h o n g , X U E Weny i n g , L I U Xiang-hua , W A N G Guo-dong ( S t a t e K e y Laboratory o f Rolling Technology and Automation , Northeastern University, Shenyang 11 0004 , Liaoning , C h i n a ) Abstract: Software of forecasting finish rolling temperature for HSM was developed based on the traditional strip temperature dropping model. According to the main cooling mode, several areas of heat transfer were separated. T h e software proved its precision to be satisfactory, Key words: hot rolling strip; finish rolling temperature; software development; HSM [cf. 2007,19 ( 1) :601
Recent Progress of Interlayer Used to Join Metals and Ceramics Z H A N G Yong , H E Zhi-yong , FENG Di ( H i g h Temperature Material Research Institute , Central Iron and Steel Research Institute, Beijing 100081 , Ch inu ) Abstract: T h e research progress of interlayer used for brazing, diffusion bonding and partial transient liquid phase bonding (PTLPB) of metals and ceramics was discussed, According to different assembled methods, the interlayer is divided into singlelayer interlayer, composite interlayer and gradient interlayer which are introduced respectively. T h e interlayer of joining Sic ceramics and SiC ceramics matrix composite to metals is also analyzed. Key words: metal; ceramics; interlayer; joining [cf. 2007,19(2):1]
Raceway Section Temperature Measurement Algorithm Based on Machine Vision OUYA N G Qi , W E N Liang-ying , B A I Chenguang , Z H A N G S h e n g - f u (College o f Materials Science and Engineering , Chongqing U n i v e r s i t y , Chongqing 4 0 0 0 4 4 , C h i n a ) Abstract: T h e relational model based on machine vision between two-dimension temperature field grads distribution of the blast furnace raceway section and radiation image information is established by the calculus ideas. Due to the problem of CCD supersaturation current output in the process of CCD non-contact raceway high temperature measurement, so the CCD shutter control model is also provided to prevent from the supersaturation current output and exceed the CCD noise
Vol. 14
signal. T h e results of experiments on a mini-type coal gas furnace and practice test show that the algorithm is accurate and credible, a t the same time, the shutter control model, which is effective for avoiding image incandescence phenomena, improves temperature measurement range. Key words: raceway; pulverized coal combustion; temperature grad 9 machine vision [ ~ f2007,19(2):5] .
Behaviour of Sulphur and Control of Sulphur in CHARP Process GUO M i n g - w e i , X U Meng , Z H A N G Jian-liang , K O N G Ling-tan , W A N T i a n - j i , H U A N G W u - d i (School o f Metallurgicul and Ecological Engineeri n g , University o f Science and Technology Beij i n g , Beijing 100083, China) Abstract:The behavior of sulfur, sulfur distribution and methods of decreasing or controlling the sulfur content in iron bead have been investigated during the reduction and melting in ore/coal composite pellets in the coal hot-air rotary hearth furnace process ( C H A R P ) . From experimental results. it has been concluded that, in addition to controlling the sulfur content in raw materials and hearth layer material, residence time of molten iron bead in the furnace should be shorten after its formation to prevent the absorption of sulfur from hearth layer material, the addition of sulfur fixation agent to hearth layer material is in favor of the decrease of sulfur in iron bead. The experiment demonstrates that the basicity has less effect on the decrease of sulfur in iron bead, while the addition of Na,CO, or MnOz in ore/coal composite pellets has a remarkable effect on that. The oxidation atmosphere can promote the volatilisation of sulfur in pellets. Key words: rotary hearth furnace; ore/coal composite pellet; iron bead; reduction; melting [cf. 2007 t 1 9 ( 2 ) : l o ]
Numerical Simulation of Molten Steel Flow in Argon Bottom Blown Tundish Z H A N G M e i - j i e , W A N G Hou-zhi , GU Hua-zhi , H U A N G Ao ( H u b e i Province K e y Laboratory u / Refractories and Ceramics, W u h u n University o f Science and Technology, Wuhun 430081 , Hubei, China) Abstract: According to the structure and the operating parameters of tundish at some plant, Eulerian multiphase model was applied, gas inlet boundary condition was defined as gas flowing through porous media, molten steel flow in the gas botom blown tundish was calculated using CFX software. The results indicate that when dams or weirs were substituted by gas blowing, the molten steel flow has no good effect on inclusion removal. T h e position of gas blowing has great effect on the molten steel flow when turbulence inhibitor, dams, weirs and gas blowing were adopted at the same time, and the most advantageous position is between weir and turbulence inhibitor.
No. 3
*v*
Journal of Iron and Steel Research. International
Key words: tundish;gas bottom blowing; numerical simulation; fluid field [cf. 2007,19(2):16]
FFT Algorithm Sampled With Hanning-Window for Roll Eccentricity Analysis and Compensation L l Yong' , H U Xian-Lei' , W A N G J u n ' , L l U Xiang-huu' , L I Hai-tao' ( I. State K e y Laborator y of Rolling and Automation , Northeastern University, Shenyang 110004 , Liaoning , China ; 2. Cold Mill P l a n t , Tangshan Iron and Steel Co L t d , Tangshan 06301 6 , Hebei, China) Abstract: A novel modified FFT algorithm sampled with Hanning-window is presented, which can be used for the thickness deviation diagnosis of strip and roll eccentricity compensation. It can effectively reduce the estimated error caused by the leakage of FFT and is more accurate than FFT and common modified F F T algorithm. T h e simulation and experiment results show that this algorithm is very accurate and better for roll eccentricity analysis and compensation. Key words: hanning-window sampling; F F T ; thickness deviation diagnosis; roll eccentricity compensation;gauge control [cf. 2007,19(2) :20]
Realization of Simulation Regarding Strip Cooling Control Process W A N G Xiao-lin , L I U Hong-shen ( College of Computer Science, Anhui University of Technolog y , Mu'ctnshan 243002, A n h u i , China) Abstract: Cooling control strategy influences the mechanical properties of strip and the study of cooling control strategy is very valuable. After the practical process of producing strips is analyzed, a new scheme of simulating the cooling process in strip production is presented . T h e scheme can reproduce the data and represent control result in the temperature control process during production. It provides an off-line manner of debugging the program module for controlling temperature and is important for researching the cooling control strategy and improving the control system of cooling. Key words: laminar cooling; cooling control; temperature control; simulation
[ ~ f 2007.19(2) . :25]
Effect of Alloying Elements on Electronic Structure of NiAl Y A N G F e n g , Z H A O Dong-liang ( Division of Function Materials, Central Iron and Steel Research Institute, Beijing 100081 , China) Abstract:The change of the electronic structure in NiAl is investigated through DVM-the first principle method when A1 in NiAl is substituted by Sc, Ti, V , Cr, Mn, Fe, Co, Ni, Cu, Zn. The results including Mulliken population, density of states, the charge distribution and the cohesion energies are presented. T h e calculation of the electronic structure indicates
that the substitution atoms affect the electronic structure of Ni and Al atoms surrounding the substitution atoms, and the ductility of NiAI. For the substitution atoms studied, Fe, Co and Ni with more d electrons may be good for the ductility of NiAl. Key words:alloying elements; electronic structure; NiAl [cf. 2007.19(2):29]
Microstructure of Workpiece for Two-Roll Cross Wedge Rolling W A N G Min-ting , DU Feng-shun , W A N G Fei-xue (College of Mechanical Engineering, Yanshan U niversity, Qinhuangdao 066004 , Hebei. China) Abstract: In order to research product properties of the cross wedge rolling ( C W R ) , a series of rolling experiments have been carried out on two-roller CWR under the condition of considering the variation of the original diameter, deformation temperature, area reduction and heat treatment methods and
so on. T h e hot austenite grain distribution and the phase composition at normal temperature were obtained with the aid of metallographic analysis method after the rolled workpieces were divided at the specified position on the linear cutting machine. T h e experimental results show that decreasing rolling temperature is helpful in getting the fine austenite grain size in comparison with the conventional rolling deformation temperature, which is a kind of potential technique for improving the general properties of the workpieces. As for small diameter workpiece, martensite distribution can be obtained by immediately quenching. Key words: two-roll cross wedge rollingigrain size; phase [cf. 2007,19(2):35]
Heat Treatment of Superalloy GH4698 Q l N He-yong, J I A O L a n - y i n g , Z H A N G Beij i a n g , XUGuo-hua ( H i g h Temperature Materials Research Institute , Central Iron and Steel Research Institute, Beijing 100081 , China) Abstract :' Base on the present heat treatments of superalloy
GH4698, two new heat treatments were put forward. The new heat treatments adopted converse-twin-stage ageing methods, which included low temperature ageing firstly and then high temperature ageing, and got rid of the secondary solution treatment of old heat treatment. T h e influence of two new heat treatments on microstructures and properties of superalloy GH4698 bar was studied. A new heat treatment suited for GH4698 alloy was gained finally: 1 000 C X 8 h , AC+650 X 2 0 h, AC+775 'C X 16 h , AC. Key words: heat treatment; microstructure; property O C '
[cf.
2007.19(2):39]
Fatigue Strength of Welded Joints for Architecture Reinforcement Steel Bar With Ultrafine Grains HOU Zhen-bo' , S H l Yao-wu' , L l Xiao-yan' , T I A N Zhi-ling2 , HE Chang-hong' ( 1 . School o f
*vI*
Abstracts from Journal of Iron and Steel Research (in Chinese)
Materials Science and Engineering, Beijing University o f Technology, Beijing 100022, China; 2. lnstitute f o r Structural Materials, Central Iron and Steel Research Institute, Beijing 100081 , China) Abstract: Ultrafine grained steel is a new generation steel. A greatdeal of attention to has been paid the effect of welding process on fatigue performance. In the present work, fatigue lifetime has been measured for flash butt welded joints and electrical slag welded joints of the ultrafine grained steel, based on a standard of State Architecture Ministry named “Testing method of reinforcement steel bar welded joint”. It is found that the fatigue lifetime of flash welded joint is higher than that of electrical slag welded joint. With the decrease of load, the gap between the both becomes small. For the of 2 000 000 cycles. the fatigue strength of the both is almost the same. Key words: ultrafine grained steel: welded joint; fatigue strength [cf. 2007,19(2):43]
Control and Optimization of Cold Plate Leveler for Heavy Plate M I A 0 Jian-sin , LIU f e i , FANG Ying , P E l Ruilin (Baosteel Branch Heavy Plate M i l l , Shanghai 200941, China) Abstract:In the heavy plate mill, cold plate leveler play an important role in the finishing area, and Simatic TDC (technology drive control) control technical of Siemens in Germany are used, which can fulfil control function and task. The control functions and features of the cold plate leveler in baosteel heavy plate mill are introduced. Key words: cold plate leveler; automatic control ;optimization [cf. 2007,19(2):47]
Application of AFNNC to Bending Rolls Control SUN Xin-yu’ , QIAO Jun-fei’ , W A N G Xiao-bo2 ( 1 . School o f Electronic and Control Engineering, Beijing University o f Technology, Beijing 100022 , China ; 2 . Baosteel Technology Center, Automation Research Institute, Shanghai 201 9 0 0 , China) Abstract: In view of the time variability and the non-linear character in rolling mills, for example UC rolling mill, a A F N N C with self-adapting ability is developed after a PID
Vol. 14
controller have been finished. Compared with PID controller, the simulation shows that AFNNC has more desirable performance in self-adapting ability and robustness. This control method is very useful for improving the quality of shape control. Key words: shape control; AFNNC; hydraulic pressure bending rolls [cf. 2007,19(2) :521
On-Line Application of Plan View Pattern Control Function for Plate Mill J l A O Z h i - j i e ’ , HUXian-lei’ , Z H A O Z h o n g ’ , LI Hai-tao’ , GUO Jian- f e i ’ , L l U Xiang-hua’ ( I. State K e y Laboratory o f Rolling and Automation, Northeastern University, Shenyang 110004 , Liaoning, China; 2. Cold Mill P l a n t , Tangshan Iron and Steel Co Ltd , Tangshan 063016 , Hebei, China ) Abstract:The theory control model for the plan view pattern control function was simplified; the relation between the thickness and the length of the taper was simplified and a linear relationship was obtained. Using the forward slip model with the adhesion condition, the taper rolling time can be calculated by discrete treatment. The control parameters can be got and the results should be checked and be corrected if over limit. T h e plan view pattern control function had been used on-site, and better effect had been got. Key words:plate mil1;plan view pattern contro1:control model; forward slip; application on site [rf. 2007,19(2) ,561
Development of On-Line Thick Metal Strip Sampling Equipment J l N Ming ( X i n y e Hi-Tech Group Co L t d , Central Iron and Steel Research Institute, Beijing 100081 , China) Abstract:Base on the status of metal strip manufacture and API sampling standard required, we design an on-line metal strip sampling equipment which can increase the speed of API sampling standard required. On-line inspection can be carried out rapidly. Key words: thick metal strip: sampling equipment [cf. 2007,19(2):60]
No. 3
Journal of Iron and Steel Research, International
May 2007
ABSTRACTSFrom Journal of Iron and Steel Research (in Chinese)
Technological Situation of Steel Wire for Steel Cord of Radial Tire Z H A NG X i , W A N G Chun-xu2 , S H I Qing-nunJ ( 1 . Faculty o f Materitals and Metallurgical Engineering, Kunming University o f Science and Technology, Kunming 650093, China; 2. Institute for Structural Materials, Central Iron and Steel Research Institute, Beijing 100081 , China) Abstract: According to the need for lightening of cars, requirement on strength of steel cord for radial tire is steadily increased. At present, 4 000 MPa level steel cord for radial tire is commercialized and becomes the strongest industrial material. The culminated strength of steel cord for radial tire, strengthening method, strengthening mechanism, structural change in drawing process, technology of microstructure control and technology for improving ductility through secondary processing are introduced. Key words: radial tire; steel wire; steel cord; technological progress [cf. 2007,19(1):1]
Some Aspects of Electromagnetic Continuous Casting Process With Soft-Contact Mold LEI Zuo-sheng , REN Zhong-ming , L I Wei-xuan , DENG Kang ( Shanghai Enhanced Laboratory o f Ferro-Metallurgy , Shanghai University, Shanghai 200072, China) Abstract:The development of electromagnetic continuous casting process with soft-contact mold was reviewed from four aspects: the distribution of electromagnetic field in the mold and the design of the mold, the mechanism of improving the surface qualities and meniscus behavior in electromagnetic field and the electromagnetic field type' s development in the process. The remarhable were pointed out. Key words: continuousfa casting; electromagnetic continuous casting; soft-contact mold [cf. 2007,19(1) :S]
Simulative Research on Coke Strength in Lumpish Section of Blast Furnace F A N G J u e , W A N G Xing-juan, GONG Rui-juan, R E N Rong-xia (College of Metallurgy and Energ y , Hebei Polytechnic University, Tangshan 063009, Hebei, China) Abstract: The relationship between temperature, carbon loss
rate and compression strength of coke in the lumpish section of blast furnace was investigated. A simulative research on the lumpish section in a blast furnace was completed using a hot model. The compression strength of the coke samples was measured using a compression testing machine with adjustable atmosphere at practical temperatures. The distribution of coke strength after reaction was obtained. In the indirect reduction section of blast furnace, the relationship between compression strength of coke and temperature is linear. In the lower section, the strength decreases rapidly with the rising of the temperature. The carbon loss rate of coke is the main factor affecting its strength. In the condition with high coal rate, coals with good reactivity and a suitable combustion ratio should be used to protect the coke strength. Key words: coke; practical temperature; compression strength; carbon loss rate; blast furnace [cf. 2007,19(1) :12]
Mathematical Model for Description of Liquid Momentum Transport Within Packed Bed Existing Inside Blast Furnace W A N G Cheng-shun' , Z H E N G Shao-bo2 , J I A N G Guo-chang' , X I A O Xing-guo3 , W A N G Wenzhong ( 1 . College o f Materials Science and Engineering, Chongqing University , Chongqing 400044, China; 2. State Enhance Laboratory of Ferro-metallurgy , Shanghai University , Shanghai 200072 , China ; 3 . School o f Materials and Metall u r g y , Northeastern University, Shenyang 110004 , Liaoning , China) Abstract: With regard to the existent mathematical model describing the liquid momentum transport within the packed bed utilized in iron-making process, there are some obstacles in engineering design, or some severe limitations in mathematical descriptions. In this paper, the effects on the liquid flow of the packed bed were divided into two parts: resistance action and dispersal action, and appropriate mathematical descriptions were given to the two actions respectively. Consequently, a new mathematical model of describing liquid flow inside packed bed was built, The results show that the model presented here could simulate the iron-making process such as blast furnace process much more appropriately. Key words: mathematical model; liquid flow; packed bed; ironmaking process [ ~ f2007,19(1):16] .
Abstracts from Journal of lron and Steel Research (in Chinese)
*I[*
Continuous Casting Technology of Mn-Si Ferrous AlIOY
W A N G Mei' , Z H A O Zongg e n g ' , Z E N G S h i - l i n 3 , LIANG Jian-qiang3, LU Bing ( 1 . National Engineering Research Center of Continuous Casting Technology Central Iron and Steel Research Institute, Beijing 100081 , China ; 2 . School of Materials Science and Engineeri n g , Hebei University of Science and Technology , Shijiazhuang 050054 , Hebei, China; 3 . Department of Science and Technology , Guangxi Bayi Ferrous A l l o y Ltd , Liuzhou 54610 2 , Guangxi, China)
YAO Shu-fang'
,
Abstract:The techniques and the internal and external qualities of continuous cast Mn-Si ferrous alloy which had been cast on a set of continuous cast experiment equipment with a special mould were studied. Some Mn-Si ferrous alloy ingots with diameter of 44, 52, 54 and 74 mm respectively were steadily continuously cast. The results show that the stability of MnSi alloy continuous cast techniques is good, the surface of MnSi alloy continuous cast ingot is smooth, the microstructure of Mn-Si alloy continuous cast ingot is fine and dense, and the quality of Mn-Si alloy continuous cast ingot is superior to that of mould cast ingot. Key words: Mn-Si; Ferrous alloy; continuous casting: mould casting
[ ~ f2007,19(1) . :22]
FEM Analysis of Influence of Vertical Roll Shape on Head and Tail Shape of Rolled Piece During Multipass V-H Rolling Process W Hai-liang' , LIU Xiang-hua' , Z H A O Xianming' , S I Liang-ying' , N I U Hai-shun' , Kusaba Y 2( 1 . The State K e y Laboratory of Rolling and Automation , Northeastern University , Shenyang 11.0004, Liaoning, China: 2. Sumitomo Metal Industries, Ltd J a p a n , 6000891 , J a p a n ) Abstract: The multipass V-H rolling process with different vertical roll shape was simutated by explicit dynamic FEM and updating geometric method, and the head and tail shape of rolled piece for different pass and vertical roll shape was analyzed. The results show that when using flat vertical roll, the wedge angle appears in tail, but it does not appear when using shape vertical roll, and the length of rolled piece is shorter than that using shape vertical roll, so its elongation is larger; when using shape vertical roll, the head and tail shape of rolled piece changs little as the groove fillet radius of roll changes. At the same time, the calculated head and tail shape of rolled piece for flat vertical roll in different pass is consistent with the measured one when the model material is lead. Key words: V-H rolling; head and tail shape8 FEM; updating geometric method [ ~ f2007,19(1):26] .
Vol. 14
Simulation Analysis of Residual Stress in Oil Casing Pipe During Sizing Rolling LI L i a n - j i n ' * z , W A N G Hui-bin2 ( 1 . College of Mechanical Engineering, Tianjin University of Commerce, Tianjin 300134 , China ; 2 . Technical Center, Tianjin Pipe Corporation Ltd , Tianjin 300301, China) Abstract: In order to eliminate the size and roundness tolerance after the rolling and heat treatment of oil casing pipe, the straightening process should be used. The sizing process, the last procedure of producing oil casing pipe, plays a key role not only in controlling the size and geometry shape of the oil casing pipe, but also in affecting the mechanical performance. Therefore, in arder to meet the size and roundness tolerance requirement of the oil casing pipe, an investigation into the relationship between the sizing reduction and residual stress and an analysis of sizing deformation process of the oil casing pipe are carried out. The goal is to reduce the residual stress of sizing process, achieve an ideal sizing result. enhance the mechanical performance of the oil casing pipe and provide a theoretical basis for making the sizing process. Key words: oil casing pipe; sizing; residual stress; carrying capacity [ ~ f2007,19(1):31] .
Thermodynamics of Carbide and Nitride Precipitation in HSLA Steel YUE Er-bin"Z, QIU Sheng-tao''2 , G A N Yong' ( I. State K e y Laboratory o f Advanced Steel Processing and Products, Beijing 100081 , China; 2. National Engineering Research Center of Continuous Casting Technology, Central Iron and Steel Research Institute, Beijing 100081 , China)
Abstract: The thermodynamics conditions of formation of carbides and nitrides in HSLA steel (16Mn steel) liquid, semisolid and solid austenite have been studied systematically. As a result, the precipitation equilibrium concentration of some related carbides and nitrides at different temperature is calculated and the precipitation sequence at different temperatures is obtained. Key words: HSLA; carbonnitrides; precipitation; thermodynamics [cf. 2007,19(1) :35]
Bauschinger Effect of Microalloyed Steel for Cold Heading Bolt in Cold Drawing Process M A Xiao-ping'", HUI Wei-jun' ? LIU Chunm i n g 2 , YU Tong-ren3 , SUN W e i 3( 1 . Institute of Structural Materials, Central Iron and Steel Research Institute, Beijing f 00081 , China ; 2 . School of Materials and Metallurgy ? Northeastern University, Shenyang 110004 , Liaoning , China ; 3. Technology Center uf Ma'anshan Iron and Steel Co
No. 3
Journal of Iron and Steel Research, International
*III*
L t d , Ma'anshan 243000, A n h u i , China)
versity, Shanghai 200072, China)
Abstract:In order to lower the flow stress in the cold heading process, the Bauschinger effect of microalloyed steel MFT8 for cold heading bolt was studied. The result shows that the Bauschinger effect increases with increasing cold-drawing reduction y. When y reaches 3 0 % - the Bauschinger effect is most significant, while the compression flow stress has a minimum value and the compression flow stress arises again when y is higher than 30%. This result is attributed to the interaction of Bauschinger effect and work hardening, that is to say, work hardening counteracts the Bauschinger effect. Key words: Bauschinger effect; cold deformation; cold hardening;microalloyed steel [ ~ f2007,19(1):39] .
Abstract: The chemical compositions of Nb-Ti and Nb-V microalloyed steels with tensile strength higher than 650 MPa are designed. The orthogonal test design method is used to investigate the effect of heating temperature, finish rolling temperature and finish cooling temperature on the mechanical properties of the two test steels. The experimental results show that the most important parameter affecting mechanical properties of the Nb-Ti and Nb-V microalloyed steels is heating temperature and finish cooling temperature respectively. The regression formulas describing the relations between A and Re and R,/R, and Re of the two steels are deduced. Key words: microalloyed steel; hot rolling temperature parameter; mechanical property [cf. 2007,19(1):48]
Solidification Segregation of Continuous Cast Steel Billets and Structure Heredity of High Strength Hot Rolled Rods H U A N G Z h e n - y i ' * 2 * 4C, H E N Guang' , N I U Yaran' , W A N G G ~ a n g - p e n g ~H ' ~U,A N G Y i - x i n 3 , L I U Wen-sue3( 1 Department o f Material Science and Engineering, Nanjing University o f Science and Technology, Nanjing 210094, Jiangsu, China; 2 . School o f Material Science and Engineeri n g , Anhui University o f Technology, Ma'anshan , 243002 , Anhui , China ; 3. Technological Center, Nanjing Iron and Steel Group Co L t d , Nanjing 210035, J i a n g s u , China; 4 . The K e y Lab o f Material and Processing, Anhui University of Technology, Ma'anshan 243002, A n h u i , China)
.
Abstract: The relationship between the element segregation of high carbon and high strength hot rolled rods and solidification structure is studied by SEM observation and chemical analysis. The results show that the formation of segregation band is mainly caused by serious segregation of C and Mn the segregation band is not sorbitic structure and has high strength and low plasticity. There are microcrack and microhole in them. The radical cause is serious segregation of continuous cast steel billets. The hot rods inherit segregation of continuous cast steel billets directly and the segregation greatly influences structure and property of hot rolled rods. According to heredity of segregation of continuous cast steel billets, effective measures have been taken against segregation. Key words: hot rod; segregation; continuous cast steel billet; heredity [ c f . 2007,19(1) :44]
Effect of Hot Rolling Parameters on Mechanical Properties of Nb-Ti and Nb-V Microalloyed Steels QlU Yu-bin' , L I N Da-wei' , H A N An-chang' ( 1 . Manu facture Department, Baoshan Iron and Steel , Shanghai 201900, China; 2. Materials Science and Engineering Institute, Shanghai Uni-
Co Ltd
Corrosion of Low-Carbon Nb Microalloyed Steel in Seawater W A N G Shu-lan, YANG Hui , Z H U A N G Li-jun (School o f Science, Northeastern University, Shenyang 11 0004 , Liaoning , China) Abstract: Niobium is one of the most effective microalloying elements of steel and has been used in niobium bearing steel for the construction of large ships and sea engineering. The corrosion behavior of niobium bearing steel in sea water is therefore very important. In this work, A. C. impedance spectra and corrosion potential of low-carbon Nb microalloyed steels at different corrosion stages were measured systematically, the charge transfer resistances of corrosion process were obtained and the charge transfer resistances increased with increasing the corrosion period. The results show that the corrosion resistance of the low-carbon Nb microalloyed steel is better than that of the niobium-free steel. Key words: Nb microalloyed steel; corrosion; impedance; charge transfer resistance [cf. 2007,19(1):53]
Preparatory Study on Optimal Control of Electro-Hydraulic Fatigue Testing Machine Z H A N G Fu-bo , W A N G Guo-dong , Z H A N G Dianh u a , L I U Xiang-hua ( S t a t e K e y Laboratory o f Rolling and Automation , Northeastern University, Shenyang 110004 , Liaoning , China) Abstract: Concerning the bad control effect for fatigue testing machine caused by variations of system parameters such as sample rigidity, oil temperature, interior leakage and so on, a method that can optimize the controller parameters on-line is brought forward. Based on the process parameters on-line identified by monitor computer, the PID parameters are optimized using the method of minimizing the objective function known as ITAE, thus the controller parameters suited for the current operating mode are obtained. This process is run at intervals of ten minutes automatically in monitor computer, and then the optimized PID parameters are transferred to controller through bus for real time control. Compared with the
*Iv*
Abstracts from Journal of Iron and Steel Research (in Chinese)
traditional method of tuning PID parameters according to experience, this method is simpler and improves the frequency response of the system. Key words: electrohydraulic servo control; fatigue testing machine; PID control1er;optimal control [cf. 2007,19(1):57]
A Simulation Software for Forecasting Finish Rolling Temperature for Hot Strip Mill GONG Dian-yao, X U J i a n - z h o n g , X U E Weny i n g , L I U Xiang-hua , W A N G Guo-dong ( S t a t e K e y Laboratory o f Rolling Technology and Automation , Northeastern University, Shenyang 11 0004 , Liaoning , C h i n a ) Abstract: Software of forecasting finish rolling temperature for HSM was developed based on the traditional strip temperature dropping model. According to the main cooling mode, several areas of heat transfer were separated. T h e software proved its precision to be satisfactory, Key words: hot rolling strip; finish rolling temperature; software development; HSM [cf. 2007,19 ( 1) :601
Recent Progress of Interlayer Used to Join Metals and Ceramics Z H A N G Yong , H E Zhi-yong , FENG Di ( H i g h Temperature Material Research Institute , Central Iron and Steel Research Institute, Beijing 100081 , Ch inu ) Abstract: T h e research progress of interlayer used for brazing, diffusion bonding and partial transient liquid phase bonding (PTLPB) of metals and ceramics was discussed, According to different assembled methods, the interlayer is divided into singlelayer interlayer, composite interlayer and gradient interlayer which are introduced respectively. T h e interlayer of joining Sic ceramics and SiC ceramics matrix composite to metals is also analyzed. Key words: metal; ceramics; interlayer; joining [cf. 2007,19(2):1]
Raceway Section Temperature Measurement Algorithm Based on Machine Vision OUYA N G Qi , W E N Liang-ying , B A I Chenguang , Z H A N G S h e n g - f u (College o f Materials Science and Engineering , Chongqing U n i v e r s i t y , Chongqing 4 0 0 0 4 4 , C h i n a ) Abstract: T h e relational model based on machine vision between two-dimension temperature field grads distribution of the blast furnace raceway section and radiation image information is established by the calculus ideas. Due to the problem of CCD supersaturation current output in the process of CCD non-contact raceway high temperature measurement, so the CCD shutter control model is also provided to prevent from the supersaturation current output and exceed the CCD noise
Vol. 14
signal. T h e results of experiments on a mini-type coal gas furnace and practice test show that the algorithm is accurate and credible, a t the same time, the shutter control model, which is effective for avoiding image incandescence phenomena, improves temperature measurement range. Key words: raceway; pulverized coal combustion; temperature grad 9 machine vision [ ~ f2007,19(2):5] .
Behaviour of Sulphur and Control of Sulphur in CHARP Process GUO M i n g - w e i , X U Meng , Z H A N G Jian-liang , K O N G Ling-tan , W A N T i a n - j i , H U A N G W u - d i (School o f Metallurgicul and Ecological Engineeri n g , University o f Science and Technology Beij i n g , Beijing 100083, China) Abstract:The behavior of sulfur, sulfur distribution and methods of decreasing or controlling the sulfur content in iron bead have been investigated during the reduction and melting in ore/coal composite pellets in the coal hot-air rotary hearth furnace process ( C H A R P ) . From experimental results. it has been concluded that, in addition to controlling the sulfur content in raw materials and hearth layer material, residence time of molten iron bead in the furnace should be shorten after its formation to prevent the absorption of sulfur from hearth layer material, the addition of sulfur fixation agent to hearth layer material is in favor of the decrease of sulfur in iron bead. The experiment demonstrates that the basicity has less effect on the decrease of sulfur in iron bead, while the addition of Na,CO, or MnOz in ore/coal composite pellets has a remarkable effect on that. The oxidation atmosphere can promote the volatilisation of sulfur in pellets. Key words: rotary hearth furnace; ore/coal composite pellet; iron bead; reduction; melting [cf. 2007 t 1 9 ( 2 ) : l o ]
Numerical Simulation of Molten Steel Flow in Argon Bottom Blown Tundish Z H A N G M e i - j i e , W A N G Hou-zhi , GU Hua-zhi , H U A N G Ao ( H u b e i Province K e y Laboratory u / Refractories and Ceramics, W u h u n University o f Science and Technology, Wuhun 430081 , Hubei, China) Abstract: According to the structure and the operating parameters of tundish at some plant, Eulerian multiphase model was applied, gas inlet boundary condition was defined as gas flowing through porous media, molten steel flow in the gas botom blown tundish was calculated using CFX software. The results indicate that when dams or weirs were substituted by gas blowing, the molten steel flow has no good effect on inclusion removal. T h e position of gas blowing has great effect on the molten steel flow when turbulence inhibitor, dams, weirs and gas blowing were adopted at the same time, and the most advantageous position is between weir and turbulence inhibitor.
No. 3
*v*
Journal of Iron and Steel Research. International
Key words: tundish;gas bottom blowing; numerical simulation; fluid field [cf. 2007,19(2):16]
FFT Algorithm Sampled With Hanning-Window for Roll Eccentricity Analysis and Compensation L l Yong' , H U Xian-Lei' , W A N G J u n ' , L l U Xiang-huu' , L I Hai-tao' ( I. State K e y Laborator y of Rolling and Automation , Northeastern University, Shenyang 110004 , Liaoning , China ; 2. Cold Mill P l a n t , Tangshan Iron and Steel Co L t d , Tangshan 06301 6 , Hebei, China) Abstract: A novel modified FFT algorithm sampled with Hanning-window is presented, which can be used for the thickness deviation diagnosis of strip and roll eccentricity compensation. It can effectively reduce the estimated error caused by the leakage of FFT and is more accurate than FFT and common modified F F T algorithm. T h e simulation and experiment results show that this algorithm is very accurate and better for roll eccentricity analysis and compensation. Key words: hanning-window sampling; F F T ; thickness deviation diagnosis; roll eccentricity compensation;gauge control [cf. 2007,19(2) :20]
Realization of Simulation Regarding Strip Cooling Control Process W A N G Xiao-lin , L I U Hong-shen ( College of Computer Science, Anhui University of Technolog y , Mu'ctnshan 243002, A n h u i , China) Abstract: Cooling control strategy influences the mechanical properties of strip and the study of cooling control strategy is very valuable. After the practical process of producing strips is analyzed, a new scheme of simulating the cooling process in strip production is presented . T h e scheme can reproduce the data and represent control result in the temperature control process during production. It provides an off-line manner of debugging the program module for controlling temperature and is important for researching the cooling control strategy and improving the control system of cooling. Key words: laminar cooling; cooling control; temperature control; simulation
[ ~ f 2007.19(2) . :25]
Effect of Alloying Elements on Electronic Structure of NiAl Y A N G F e n g , Z H A O Dong-liang ( Division of Function Materials, Central Iron and Steel Research Institute, Beijing 100081 , China) Abstract:The change of the electronic structure in NiAl is investigated through DVM-the first principle method when A1 in NiAl is substituted by Sc, Ti, V , Cr, Mn, Fe, Co, Ni, Cu, Zn. The results including Mulliken population, density of states, the charge distribution and the cohesion energies are presented. T h e calculation of the electronic structure indicates
that the substitution atoms affect the electronic structure of Ni and Al atoms surrounding the substitution atoms, and the ductility of NiAI. For the substitution atoms studied, Fe, Co and Ni with more d electrons may be good for the ductility of NiAl. Key words:alloying elements; electronic structure; NiAl [cf. 2007.19(2):29]
Microstructure of Workpiece for Two-Roll Cross Wedge Rolling W A N G Min-ting , DU Feng-shun , W A N G Fei-xue (College of Mechanical Engineering, Yanshan U niversity, Qinhuangdao 066004 , Hebei. China) Abstract: In order to research product properties of the cross wedge rolling ( C W R ) , a series of rolling experiments have been carried out on two-roller CWR under the condition of considering the variation of the original diameter, deformation temperature, area reduction and heat treatment methods and
so on. T h e hot austenite grain distribution and the phase composition at normal temperature were obtained with the aid of metallographic analysis method after the rolled workpieces were divided at the specified position on the linear cutting machine. T h e experimental results show that decreasing rolling temperature is helpful in getting the fine austenite grain size in comparison with the conventional rolling deformation temperature, which is a kind of potential technique for improving the general properties of the workpieces. As for small diameter workpiece, martensite distribution can be obtained by immediately quenching. Key words: two-roll cross wedge rollingigrain size; phase [cf. 2007,19(2):35]
Heat Treatment of Superalloy GH4698 Q l N He-yong, J I A O L a n - y i n g , Z H A N G Beij i a n g , XUGuo-hua ( H i g h Temperature Materials Research Institute , Central Iron and Steel Research Institute, Beijing 100081 , China) Abstract :' Base on the present heat treatments of superalloy
GH4698, two new heat treatments were put forward. The new heat treatments adopted converse-twin-stage ageing methods, which included low temperature ageing firstly and then high temperature ageing, and got rid of the secondary solution treatment of old heat treatment. T h e influence of two new heat treatments on microstructures and properties of superalloy GH4698 bar was studied. A new heat treatment suited for GH4698 alloy was gained finally: 1 000 C X 8 h , AC+650 X 2 0 h, AC+775 'C X 16 h , AC. Key words: heat treatment; microstructure; property O C '
[cf.
2007.19(2):39]
Fatigue Strength of Welded Joints for Architecture Reinforcement Steel Bar With Ultrafine Grains HOU Zhen-bo' , S H l Yao-wu' , L l Xiao-yan' , T I A N Zhi-ling2 , HE Chang-hong' ( 1 . School o f
*vI*
Abstracts from Journal of Iron and Steel Research (in Chinese)
Materials Science and Engineering, Beijing University o f Technology, Beijing 100022, China; 2. lnstitute f o r Structural Materials, Central Iron and Steel Research Institute, Beijing 100081 , China) Abstract: Ultrafine grained steel is a new generation steel. A greatdeal of attention to has been paid the effect of welding process on fatigue performance. In the present work, fatigue lifetime has been measured for flash butt welded joints and electrical slag welded joints of the ultrafine grained steel, based on a standard of State Architecture Ministry named “Testing method of reinforcement steel bar welded joint”. It is found that the fatigue lifetime of flash welded joint is higher than that of electrical slag welded joint. With the decrease of load, the gap between the both becomes small. For the of 2 000 000 cycles. the fatigue strength of the both is almost the same. Key words: ultrafine grained steel: welded joint; fatigue strength [cf. 2007,19(2):43]
Control and Optimization of Cold Plate Leveler for Heavy Plate M I A 0 Jian-sin , LIU f e i , FANG Ying , P E l Ruilin (Baosteel Branch Heavy Plate M i l l , Shanghai 200941, China) Abstract:In the heavy plate mill, cold plate leveler play an important role in the finishing area, and Simatic TDC (technology drive control) control technical of Siemens in Germany are used, which can fulfil control function and task. The control functions and features of the cold plate leveler in baosteel heavy plate mill are introduced. Key words: cold plate leveler; automatic control ;optimization [cf. 2007,19(2):47]
Application of AFNNC to Bending Rolls Control SUN Xin-yu’ , QIAO Jun-fei’ , W A N G Xiao-bo2 ( 1 . School o f Electronic and Control Engineering, Beijing University o f Technology, Beijing 100022 , China ; 2 . Baosteel Technology Center, Automation Research Institute, Shanghai 201 9 0 0 , China) Abstract: In view of the time variability and the non-linear character in rolling mills, for example UC rolling mill, a A F N N C with self-adapting ability is developed after a PID
Vol. 14
controller have been finished. Compared with PID controller, the simulation shows that AFNNC has more desirable performance in self-adapting ability and robustness. This control method is very useful for improving the quality of shape control. Key words: shape control; AFNNC; hydraulic pressure bending rolls [cf. 2007,19(2) :521
On-Line Application of Plan View Pattern Control Function for Plate Mill J l A O Z h i - j i e ’ , HUXian-lei’ , Z H A O Z h o n g ’ , LI Hai-tao’ , GUO Jian- f e i ’ , L l U Xiang-hua’ ( I. State K e y Laboratory o f Rolling and Automation, Northeastern University, Shenyang 110004 , Liaoning, China; 2. Cold Mill P l a n t , Tangshan Iron and Steel Co Ltd , Tangshan 063016 , Hebei, China ) Abstract:The theory control model for the plan view pattern control function was simplified; the relation between the thickness and the length of the taper was simplified and a linear relationship was obtained. Using the forward slip model with the adhesion condition, the taper rolling time can be calculated by discrete treatment. The control parameters can be got and the results should be checked and be corrected if over limit. T h e plan view pattern control function had been used on-site, and better effect had been got. Key words:plate mil1;plan view pattern contro1:control model; forward slip; application on site [rf. 2007,19(2) ,561
Development of On-Line Thick Metal Strip Sampling Equipment J l N Ming ( X i n y e Hi-Tech Group Co L t d , Central Iron and Steel Research Institute, Beijing 100081 , China) Abstract:Base on the status of metal strip manufacture and API sampling standard required, we design an on-line metal strip sampling equipment which can increase the speed of API sampling standard required. On-line inspection can be carried out rapidly. Key words: thick metal strip: sampling equipment [cf. 2007,19(2):60]