IRON AND STEEL

钢铁

Home | About Journal | Editorial Board | Instruction for Authors | Subscriptions | Advertisement | Contacts Us | Chinese

　

Office Online

　

　

　

　

　

　

Editor-in-chief

　

Journal Online

　

　

Forthcoming Articles

　

　

　

　

Download Articles

　

　

Quick Search

Advanced Search

	2018 Vol. 53 No. 8
	Published: 2018-08-15

	1	ZHAO Pei，DONG Peng-li
		Carbon emission cannot be ignored in future of Chinese steel industry
		Background of carbon emission and control measures taken by European Union countries in the situation of global climate warming are summarized. Main measures and achievements for controlling carbon emissions of China are also introduced. Research and development in carbon emission control of steel industry，and corresponding cutting-edge technologies in EU，US，South Korea and Japan are presented intensively. Furthermore，BAT technology for energy saving and emission reduction，green process，green manufacturing products，green logistics and new technology are also introduced. A reference for the carbon emission reduction of China steel industry is provided，aiming to draw the attention of steel enterprises to carbon emissions.
		2018 Vol. 53 (8): 1-7 [Abstract] ( 464 ) [HTML 1KB] [PDF 1022KB] ( 1392 )

	8	JING Jia-qiang，GUO Jie，，LIU Qing-you，HOU Wei
		Research progress of low temperature’s effect on pipeline steel stability and welding technology
		Along with the extension of the long distance oil and gas pipeline to the alpine region，the construction，operation and maintenance of long distance oil and gas pipelines are affected by the low temperature environment. This makes the selection of pipeline steel materials，structural integrity assessment and safe operation of pipelines critical in low temperature environment. The literatures about fatigue life，crack generation and growth，welding technology and weld fatigue stability of pipeline steel are reviewed. The mechanism of the effect of low temperature environment on the fatigue crack generation and the expansion and the mechanical properties and the fatigue stability of the weld of pipeline steel is revealed. The problems existing in the present study are summarized，and on this basis，the key points for future research are put forward.
		2018 Vol. 53 (8): 8-14 [Abstract] ( 348 ) [HTML 1KB] [PDF 891KB] ( 799 )

	15	LI Jian，MAO Xiao-ming，PENG Xin
		Effect of micro-characteristics on reduction degradation index of sinter
		In order to study the pressure difference and stability of BF are quite different when using two kinds of sinter with the same chemical composition，. After the two kinds of sinter were sprayed with calcium chloride solution，RDI were carried out. It is found that calcium chloride solution has no effect on A sinter，but it can significantly reduce the RDI of B sinter. Further，the difference of microstructure of two sinter was measured by real density detector，optical microscope，image analysis and nanomechanical test system. Sinter A has high porosity，fine grain，low phase hardness and poor strength. After calcium chloride was sprayed，some interfaces were isolated at the initial stage of reduction process. With the reaction interface expanding rapidly，the low structure strength of the sinter is difficult to resist the reducing stress. Thus，the RDI was not improved. After the sinter B was sprayed by calcium chloride solution，a protective film can be formed to isolate the gas solid reaction. Because sinter B has low porosity，coarse grain，small reaction interface，high phase hardness and high strength，it can well resist the reducing stress. Spraying different amounts of CaCl2 solution can reduce the RDI by 10.00%-27.25%. The results show that microstructure is one of the important factors for the difference of RDI.
		2018 Vol. 53 (8): 15-20 [Abstract] ( 307 ) [HTML 1KB] [PDF 1542KB] ( 1178 )

	21	REN Hua-wei，，CHU Man-sheng，Lü Qing-qing，LIU Zheng-gen，ZHANG Ming-xing
		Mechanism and influence on iron-coke property by iron ore powder
		In order to promote the industrial application of iron-coke.Research on iron ore powder ingredient and ratio in iron-coke which was made by 40 kg pilot coke oven was carried on to find how both affect iron-coke’s ash，sulfur，mechanical strength，CRI and so on. The analysis on iron-coke’s microstructure was in progress by thermal analysis，SEM and microscope.Theresult shows that iron-coke’s ash and CRI increases，mechanical strength and CSR reduces，sulfur makes little change when adding iron ore powder，so the addition ratio should not exceed 10%. Iron ore powder can catalyze the reaction between coke and CO2 and reduce initial reaction temperature. The higher the iron content，the stronger the catalysis. Iron and iron oxide after reduction scatters in iron-coke stomatal wall and carbon stroma with irregular size and shape which results in an increase in CRI and a decline in CSR.
		2018 Vol. 53 (8): 21-27 [Abstract] ( 397 ) [HTML 1KB] [PDF 1635KB] ( 876 )

	28	ZHANG Heng，ZHANG Jian-liang，JIAO Ke-xin，MO Chao-xing，CHEN Ru-gang
		Analysis on damage cause to stave-plate compound cooling system of a commercial blast furnace
		Blast furnace longevity has become an important part of the progress of modern ironmaking technology. Improving furnace cooling equipment life is one of the key factors to ensure the longevity. To figure out the damage cause to the stave-plate compound cooling system and provide effective guidance for the optimal design of cooler structures and safe production，a fluid-thermal-structural coupling model was developed according to the actual size. Based on the heat transfer theory and the finite element numerical simulation，the distribution characteristics of flow field，temperature field and stress field were analyzed. Combined with the actual case of blast furnace，the essential reasons of the damage were systematically studied and the specific damaged parts were pointed out. The accuracy of the simulation analysis results is verified by the real-time recorded temperature data of a commercial blast furnace. The results show that the front two sides of the cooling plate and laminar sublayer in the water pipes are the weak link of the cooling system. Under the same condition，the temperature in the front two sides of the cooling plate is higher than that of other parts at 4.5 ℃. The deformation of the front end of the cooling plate is the largest，reaching 2 mm. The main reasons for the breakage of the cooling plate is the frequent falling of the slag skin caused by the large fluctuation of the coke quality M10 and M40 index in the production of the blast furnace.
		2018 Vol. 53 (8): 28-37 [Abstract] ( 430 ) [HTML 1KB] [PDF 2230KB] ( 1099 )

	38	XIANG Zhong-yong，JIANG Xi，
		Analysis of production indexes of large BF by new evaluation method for production efficiency
		The large blast furnace conditions in China were changed largely in those days because of the variation of burden quality，burden structure and the lower fuel ratio adaption，affecting the operation indexes and economic profits. While the stability of blast furnace was worsening by frequently change the operation system. Except insist the high burden quality policy and eliminate the environmental interference，the effective evaluation of blast furnace production efficiency could benefits to optimize the operation indexes and improve stability of the blast furnace. In the present study，a new effective evaluation method was used to analysis the operation indexes of large blast furnace in China during 2016，the results could guide the operators and relative technician to find the reasonable operation systems for large blast furnace.
		2018 Vol. 53 (8): 38-43 [Abstract] ( 362 ) [HTML 1KB] [PDF 938KB] ( 696 )

	44	ZHAO Jun-xue，SHANG Nan，ZHAO Zhong-yu，SHI Rui-meng，LU Liang， WANG Ze
		Influence of slag preparation mode on melting point of ESR slag with medium fluoride content
		The reasons of the difference in melting point measured by hemispherical method is studied for samples of slag for electroslag remelting with the same composition and different modes of slag matching，in order to further understand the characteristics of fluorine slag system during heating，melting point determination experiment and electroslag preparation process to provide reference. Hemispherical melting point measurement and thermogravimetric analysis were carried out on pre-melting slag and the slag with the same chemical composition made from chemical pure reagent. The two kinds of slag were calcined in the same condition as the melting point measurement，and the phase analysis were carried out for the calcined samples. The results showed that the average melting point difference between the two groups was about 72 ℃，and there was a significant weightloss during the heating process. The weight loss of the samples prepared by chemical pure reagent （7.79%） was significantly higher than that of the premelting slag （1.11%）. Weightloss mainly originates from the volatilization of CaF2 in the process of high temperature. Calcium fluoride volatilization caused slag composition change，resulting in phase change. Cooling sample from chemical pure agent after melting contains a large amount of cuspidine and spinel，which are high melting point materials. Cooling sample from premelting slag after melting contains a lot of melilite and two calcium aluminate，which are low melting point phases. Therefore，the main reason of the difference in melting point among slag samples with the same composition and different modes of slag matching is that the volatilization of the two groups of slag is different，leading to the difference in the chemical composition and phases，and as a result，the difference in melting point.
		2018 Vol. 53 (8): 44-48 [Abstract] ( 283 ) [HTML 1KB] [PDF 1223KB] ( 631 )

	49	CHEN Liang，，SONG Bo，CHEN Tian-ming，CHEN Xiong，YANG Wen-zhong
		Control countermeasures of center porosity and shrinkage in 45 steel continuous casting bloom
		In order to reduce the rate of flaw detection disqualification in 45 round steel with diameters from[?200 mm]to[?250 mm]which was rolled in 360 mm×450 mm bloom. The main causes of flaw detection disqualification were center segregation and porosity of blooms. The casting speed，secondary cooling water and electromagnetic stirring at end of solidification were contrast tested. The roller of heavy reduction was optimized. Microscopy，scanning spectrometer and true density of the blooms were analyzed. The results show that the 0.45 m/min casting speed and low secondary cooling water with 300A and 2.4 Hz parameters of electromagnetic stirring were benefit to the equiaxed grains expanding. The biggest area of equiaxed grains was 280 mm×170 mm.The true density and compactness of bloom with convex roller were 8.022 6 g/cm3 and 0.998 4 respectively which was higher than that in flat roller. After comprehensive technology application，the qualification rate of flaw detection was improved form from 70.85% to 95.87% in 2 583 tons 45 round steel production.
		2018 Vol. 53 (8): 49-54 [Abstract] ( 423 ) [HTML 1KB] [PDF 1835KB] ( 1316 )

	55	SUN Hai-bo，LI Lie-jun，WU Xue-xing，YE De-xin
		Control of segregation and hardenability band width by optimizing M-EMS parameters for gear steel
		To improve the controllability of hardenability band width for gear steel products，the parameters dependence of in-mould electromagnetic stirring (M-EMS) on the component homogeneity and hardenability band width has been investigated based on the numerical simulation and plant trials. It was seen that superheat degree of liquid steel at the center of mould exit was reduced from 0.25 to －2.65 ℃，and the carbon segregation at 12 mm from strand surface decreased from 0.98 to 0.85 as the stirrer current increased from 100 to 600 A. The fluctuation range of carbon content on the cross section of roller gear steel product was firstly reduced and then increased with the increase of running current due to the integrated effects of superheat dissipation and concentration equilibrium in mold region with EMS，where the minimum fluctuation rate of 0.012% was presented under the stirrer current of 200 A. The magnitude of hardenability band could be decreased from 10HRC （max） to that less than 5HRC under the optimized M-EMS parameters of 200 A/2.5 Hz，as compared to normal case of 600 A/2.5 Hz，which was beneficial to effective control for hardenability band width.
		2018 Vol. 53 (8): 55-61 [Abstract] ( 439 ) [HTML 1KB] [PDF 1649KB] ( 743 )

	62	QIN Da-wei，，LIU Hong-min，WANG Jun-sheng，ZHANG Yan，FEI Jing，ZHANG Dong
		Coating thickness control for strip hot-dip galvanizing
		The thickness control process of strip continuous hot dip galvanizing has multiple variable coupling，nonlinear and time delay，which is difficult to model and control. At present，the domestic production line adopts manual control，and there are problems such as large thickness deviation，long adjustment time and waste of zinc raw materials. Based on the analysis of continuous hot-dip galvanizing production process，a control method combining process setting and intelligent control was presented. For the multi-variable coupling and non-linearity of the control object，the table of knife-blade and knife-height setting is established. Based on the mechanism model of the coating thickness，a database of knife-pressure formula is established and the multivariable system is simplified to a single-variable linear time-delay system. To deal with the problem of pure lag in coating thickness measurement，an iterative learning control algorithm is applied to approach the ideal knife pressure control to eliminate the coating thickness deviation. The coating thickness control system was developed by using WinAC soft PLC，and the coating thickness was automatically controlled. The application results show that the control system has good control performance，shorten the adjustment time and improve the coating thickness precision.
		2018 Vol. 53 (8): 62-67 [Abstract] ( 375 ) [HTML 1KB] [PDF 910KB] ( 941 )

	68	LI Guang-hui
		EVC-Plus technique of transverse thickness deviation control of non-oriented silicon steel during cold rolling
		To non-oriented silicon steel，transverse thickness deviation is very important and key quality target. UCM tandem cold rolling mill is taken as the research object，an integrated simulation model of 6-High Mill and thin strip is established. By this model，considering the rolling stability and transverse thickness deviation control of non-oriented silicon steel，the EVC-Plus （Edge Variable Crown-Plus） roll with special double arc chamfering was designed and applied on a 1 720 UCM tandem cold mill. The actual application results showed that the EVC-Plus can be ground easily and the transverse thickness deviation of the non-oriented silicon steel was reduced from 12 to 8 μm or less by corresponding EVC-Plus contour for different product width，and the occurrence of strip breakage accident was greatly reduced.
		2018 Vol. 53 (8): 68-72 [Abstract] ( 404 ) [HTML 1KB] [PDF 897KB] ( 782 )

	73	HAO Yong-fei，CHENG Guo-guang，XIE You
		Precipitation behavior of carbides in W4Mo3Cr4VSi high-speed steel
		In order to understand the precipitation behavior of the carbide in W4Mo3Cr4VSi(4341)，control them and greatly improve the functional performance of the steel. W4Mo3Cr4VSi steel smelt in actual production were studied. Observing and analyzing the morphology，size and composition of carbides in W4Mo3Cr4VSi steel using scanning electron microscope and energy dispersive spectrometer. The formation mechanism of these carbides were analyzed by Thermo-Calc software. The results show that two types of carbides exist in the steel. The one is W-Mo-rich carbides whose morphologies are granular which were provided to be M6C. The other is V-rich carbides whose morphologies are strips which were provided to be VC. They are both precipitated in liquid phase during solidification. During the solidification of VC，VN precipitate firstly and VC begin to precipitate only when solid mass percent is 78%. Thermal stability of carbides were also studied. M6C carbide are unstable and dissolve after holding at 1 150 ℃ for 6 h，and grain growth after holding at 1 250 ℃ for 6 h. VC carbide are relatively more stable，which dissolve little after holding at 1 150 or 1 250 ℃.
		2018 Vol. 53 (8): 73-82 [Abstract] ( 403 ) [HTML 1KB] [PDF 2808KB] ( 948 )

	83	GAO Jian-bing，FAN Si-peng，ZHANG Shu-cai，JIANG Zhou-hua，LI Hua-bing
		Segregation behavior and homogenizing treatment of a new type super austenitic stainless steel 654SMO
		The dendritic crystal morphology，element segregation and precipitation behaviors of super austenitic stainless steel 654SMO ingot were investigated by means of Thermo-Calc calculation，optical microscope （OM） and scanning electron microscope （SEM）. Based on the alloy phase diagram and kinetic homogenizing curves，the homogenization treatments of 654SMO were proposed. Through the analysis of dendritic crystal morphology，residual segregation index and precipitates after different homogenization treatments，combined with forging experiments，the reasonable homogenization treatment of 654SMO has been determined. The results show that the segregation of Mo was the most serious during the solidification of 654SMO，and the degree of segregation in the center of ingot was greater than that of the edge. Mo mainly segregated at the dendrite core and promoted the precipitation of σ phase. After homogenizing at 1 280 ℃ for 16 h，the segregation of elements was basically eliminated，the dendrite was fully melted，the precipitates were fully dissolved，and the hot ductility of the ingot has been greatly improved.
		2018 Vol. 53 (8): 83-89 [Abstract] ( 432 ) [HTML 1KB] [PDF 1585KB] ( 1022 )

	90	ZHANG Yu-cheng，MENG Zhen-sheng，MENG Yang，JU Xin-hua，JIANG Zhong-hang
		Strain induced precipitation behavior of Nb and Ti in S460ML steel
		In order to study the strain induced precipitation behavior of Nb and Ti in S460ML steel，a series of thermal simulation experiments under different conditions were carried out. The deformation temperature is 900-1 000 ℃. The strain rate is 0.1-5.0 s－1. The deformation amount is 10%-50% and relaxation time is 0-15 min. The precipitation amount and the morphology and size of the precipitates of Nb and Ti under different experimental conditions were analyzed by physical chemical phase analysis method and transmission electron microscope (TEM)，respectively. The results showed that with the increase of relaxation time and the decrease of deformation temperature，the strain induced precipitation rate of Nb and Ti increased. The increase of deformation amount could not only shorten the starting time for strain induced precipitation，but also increase the total amount of the strain induced precipitation of Nb and Ti. As the strain rate decreased，the Nb and Ti strain induced precipitation started earlier，but it showed little effect on total precipitation amount after certain relaxation time. The average size of the precipitation phase decreased with the increase of the deformation amount and relaxation time and the decrease of deformation temperature.
		2018 Vol. 53 (8): 90-95 [Abstract] ( 386 ) [HTML 1KB] [PDF 1206KB] ( 953 )

	96	ZHANG Zi-yue，YU Gang-qiang，JIANG She-ming，GAO Zhi-qiang，LIU Xin
		Effect of molybdate and borate on vanadate conversion film in hot galvanizing
		Sodium perborate and molybdate were used as accelerant to prepare the conversion fluid. The process of nucleation and growth of vanadate conversion coating were observed by scanning electron microscopy. The film weight was analyzed by chemical method and the corrosion resistance of the coating was tested by neutral salt spray test，the corrosion behavior of the coating in 5%NaCl was analyzed by electrochemical workstation. The results indicate that sodium perborate improved the mass percent of vanadium compound in the transformation film，and it was helpful to create thick and dense transformation film；sodium molybdate can promote the nucleation of conversion film and accelerate the initial growth rate of the film. In the corrosion environment，mixed valence state compound of vanadium can protect the zinc layer by inhibition the reduction of oxygen in the cathode area.
		2018 Vol. 53 (8): 96-101 [Abstract] ( 326 ) [HTML 1KB] [PDF 1268KB] ( 829 )

	102	LIU Ding-ping，YUAN Dan-jue
		Experimental research on sintering flue gas swirl atomization desulfurization and dust integration
		Aiming at ultra-clean emission requirements for sintering flue gas in iron and steel enterprises，the problems encountered in the process of sintering flue gas desulfurization and dusting were analyzed and swirl atomization desulfurization and dust integration technology was put forward. By constructing a spray tangential swirl field，desulfurization efficiency and dust removal efficiency of a desulfurization tower improved under the influence of turbulent flow，atomization and condensation. The three-day transformation test of a 2×90 m2 sintering unit desulfurization tower was carried out. The test results show that adopting swirl atomizing technology，although the inlet flue gas flow rate，inlet flue gas temperature，inlet SO2 concentration fluctuate sharply，the outlet SO2 concentration can be stabilized below 30 mg/m3 and the desulfurization efficiency can reach as high as 99.22% after reformation. When the inlet dust concentration is 50 mg/m3 and without adding a wet electrostatic precipitator，the outlet dust concentration can be stabilized below 8 mg/m3，the dust removal efficiency can reach as high as 94.3% after reformation，achieving ultra-clean emission of sintering flue gas.
		2018 Vol. 53 (8): 102-106 [Abstract] ( 389 ) [HTML 1KB] [PDF 857KB] ( 875 )

钢铁

　

News

　

　

·

·

·

·

·

　　　　　　　　　　More

　

Author Center

　

　

Instruction for Authors

　

　

Copyright Agreement

　

Links

　

·	Links

　　　　　　　　　　More

Copyright © IRON AND STEEL　
Supported by: Beijing Magtech