钢铁研究学报(英文版)
首页
期刊介绍
编 委 会
投稿指南
期刊订阅
广告服务
留言板
联系我们
English
在线办公平台
在线期刊
当期目录
论文检索
过刊浏览
论文下载排行
论文点击排行
Email Alert
文章快速检索
高级检索
2012年 19卷 11期
刊出日期：2012-11-15
材料
工艺
工艺
1
LIU Jian-hua,WANG Guo-xuan,BAO Yan-ping,YANG Yan,YAO Wei,CUI Xiao-ning
Inclusion Variations of Hot Working Die Steel H13 in Refining Process
Inclusion variations of die steel H13, including changes of species, morphologies, compositions, amounts and sizes, in the production of EAF→LF→VD→ingot casting→electro-slag refining (ESR) procedure, were investigated by systematic sampling, and analyzed with scanning electron microscope (SEM), energy dispersive spectrum (EDS), and metallographic microscope. The variation mechanism was studied by comprehensive analysis of total oxygen, nitrogen, and acid soluble aluminum as well as chemical test of refining slag. Based on the investigations, technical measures for cleanness improvement were discussed. The results show that oxide inclusions in H13 steel change from irregular Al2O3→near globular CaO-MgO-Al2O3 and CaO-Al2O3-SiO2 complex inclusions→finer CaO-Al2O3-SiO2 inclusions with higher CaO content→CaO-Al2O3-SiO2 inclusions with higher Al2O3 content and irregular MgO-Al2O3 inclusions→fine irregular MgO-Al2O3-CaS inclusions in various steps of the production; the variations are related with changes of acid soluble aluminum content, reactions between slag and steel, re-oxidation of liquid steel during casting, and refining of ESR. It is also found that Al2O3 inclusions are modified by refining slag in LF and VD refining; and ESR plays a good role in inclusion removal, especially in controlling the large linear VC-CrC-MoC inclusions distributed in grain boundaries. It is suggested that casting protection should be improved, and the basicity of refining slag and acid soluble aluminum content in steel should be raised.
2012 Vol. 19 (11): 1-7 [
摘要
] (
1711
) [
HTML
0KB] [
PDF
0KB] (
21
)
8
WANG Nan,HUANG Wei-jun,CHEN Shuai-chao,CHEN Min
Effect of Oxygen Partial Pressure on Phase Equilibria and Liquidus in CaO-Al2O3-FeOx System
A high temperature equilibration experiment was carried out to investigate the effect of oxygen partial pressure on the phase equilibria and liquidus in CaO-Al2O3-FeOx system with the intermediate oxygen partial pressures of 10.13 Pa and 1.01×10-3 Pa. The equilibrated phases and their compositions of the quenched samples were analyzed by using SEM/EPMA (Scanning Electron Microscope/Electron Probe Micro-Analysis) and XRD (X-Ray Diffraction). The phase equilibrium results include two cases, the two-phase coexistence and the three-phase coexistence in the high Al2O3 region with oxygen partial pressure of either 10.13 Pa or 1.01×10-3 Pa. Effects of oxygen partial pressure and temperature on the liquidus along the primary phase fields of CaO·Al2O3 and CaO·2Al2O3 were notable. With the decrease of oxygen partial pressure, the liquid area expands and the liquidus of CaO·Al2O3 and CaO·2Al2O3 primary fields moves to the Al2O3-FeOx region. On the other hand, the liquid area of CaO-Al2O3-FeOx system extends extremely to the high Al2O3 region with the temperature increasing from 1400 to 1500 ℃, especially at lower oxygen partial pressure. The present experiment results are in good agreement with the calculated ones by FactSage.
2012 Vol. 19 (11): 8-12 [
摘要
] (
1534
) [
HTML
0KB] [
PDF
0KB] (
24
)
13
CUI Miao,YANG Kai,LIU Yun-fei,GAO Xiao-wei
Inverse Estimation of Transient Heat Flux to Slab Surface
The transient heat flux was calculated using a model for inverse heat conduction problems based on temperature measurements. The unknown heat flux was taken as an optimization variable and solved by minimizing the differences between the calculated temperatures and the measured ones. Several examples were given to show the effectiveness and the accuracy of the inverse algorithm in estimating the transient heat flux to a slab surface. The results show that the inverse approach can be applied in the steel industry or in other areas where the target of investigation is inaccessible to direct measurements or difficult to be directly modeled.
2012 Vol. 19 (11): 13-18 [
摘要
] (
1593
) [
HTML
0KB] [
PDF
0KB] (
24
)
19
LI Jiao,WEN Guang-hua,TANG Ping,ZHU Ming-mei, GAO Jian-jun,LIU Hai-lan
Fluid Flow and Inclusion Motion in a Multi-Heat Teeming Tundish for Heavy Steel Ingot
Besides the function of molten steel supply in the casting process, tundish has a capability of decreasing the formation of macro-scale inclusions and promoting the flotation of the remaining inclusions. Both the round shape tundish and the elliptical shape tundish were studied for the multi-heat teeming ingot. The transportation of molten steel and the motion of inclusions were compared using numerical simulation and physical modeling. The results showed that the short molten steel residence time, the large dead volume, and the low efficiency in inclusion removal for the round shape tundish were obtained even when a flow control device was installed. After comparing the two kinds of tundishes with the same capacity, it indicated that in the elliptical shape tundish, the molten steel residence time was prolonged by 1.6 times and the mean residence time increased by 6%; the dead volume was decreased from 18% to 13%, the ratio of the plug volume to the dead volume increased by 68%, and the inclusion flotation efficiency increased by 17%. The trial results indicated that, after using the elliptical tundish, the equivalent diameter of single defect was decreased from 2.5 to 1.6 mm, and no intensity defect was observed. The total oxygen content was 21×10-6, which was decreased by 30%.
2012 Vol. 19 (11): 19-26 [
摘要
] (
1698
) [
HTML
0KB] [
PDF
0KB] (
18
)
27
WAN Fei,,WANG Yong-qin,QIN Shu-ren
Modeling of Strip Temperature in Rapid Cooling Section of Vertical Continuous Annealing Furnace
The strip temperature is affected by many factors in rapid cooling section (RCS) of the vertical continuous annealing furnace (VCAF). They can be divided into four types: the physical properties of cooling gas, the geometry characteristics of configuration of cooling equipment, the heat transfer between the strip and the cooling gas, and the conductivity of the strip. It aims to model the strip temperature in the cooling section based on the fundamental heat transfer theory and the four aspects factors. The model for transient Nusselt number is obtained by considering Reynolds number, Prandtl number and geometry characteristics of RCS. Then cooling model of the strip transient temperature is built by Nusselt number, heat transfer coefficient and heat conductivity of the strip. The results are compared with the data from production line. The comparisons indicate that the model can well predict cooling temperature of the strip. It is hoped that the proposed model can be used for design and control of the vertical continuous annealing furnace.
2012 Vol. 19 (11): 27-32 [
摘要
] (
1570
) [
HTML
0KB] [
PDF
0KB] (
22
)
33
ZHANG Sheng-qin,,XIE Bing,WANG Yu,GUAN Ting,CAO Hai-lian,ZENG Xiao-lan
Reaction of FeO-V2O5 System at High Temperature
FeO and V2O5 are two main components of the obtained vanadium steel slag, and the reaction of FeO-V2O5 system determines the physical property of the slag. Through thermodynamic calculation and experimental study, it can be found that within the ranges of steel-making temperature, V2O5 is reduced to VO2. As FeO exists in FeO-V2O5 system, VO2 will be reduced to V2O3 further while FeO is oxidized to Fe2O3. In this multi-system, as the content of FeO and temperature increase, the system will have products in turn such as V3O5, V3O4, FeVO4, Fe2VO4 and Fe3O4. The products are mainly V3O5 and Fe2O3 when the content of FeO is 0.58 mol and the temperature is 1100 K, and as the temperature increases, Fe2O3 starts to react with V2O5 and then generates FeVO4; FeVO4 disappears while the content of FeO and the temperature increase at the same time, and then Fe2VO4 is generated by the reaction of FeO, Fe2O3 and V2O3. Iron oxides are also generated such as Fe3O4 and so on.
2012 Vol. 19 (11): 33-38 [
摘要
] (
1854
) [
HTML
0KB] [
PDF
0KB] (
17
)
材料
39
JIANG Yong-feng,BAO Ye-feng,YANG Ke
Effect of C/N Concentration Fluctuation on Formation of Plasma Electrolytic Carbonitriding Coating on Q235
The plasma electrolytic carbonitriding (PEC/N) on the Q235 steel was investigated in an aqueous solution containing monoethanolamine and KCl in a very short period of time. The microdischarge characteristics of the voltage/current on the Q235 were observed using real-time imaging during the PEC/N. The microstructure and element distribution of the carbonitriding layer were examined using scanning electron microscope (SEM) equipped with energy dispersive spectroscope (EDS). The effect of microdischarge on roughness, thickness and microhardness was evaluated. The formation of the carbonitriding layer was discussed. Research shows that it is similar in the microstructure and properties between the plasma electrolytic carbonitriding and the traditional gas carbonitriding. The formation of the carbonitriding layer results from the carbon and nitrogen fluctuation in PEC/N process. The microhardness and thickness can be up to HV 779 and 0.360 mm in 180 s, respectively, which is close to the results of the gas carbonitriding in the microhardness. Therefore, the plasma electrolytic carbonitriding has a potential to substitute the gas carbonitriding.
2012 Vol. 19 (11): 39-45 [
摘要
] (
1591
) [
HTML
0KB] [
PDF
0KB] (
26
)
46
WANG Lei,,LIU Chang-sheng,YU Hai-yun,AN Cheng-qiang
Structure and Corrosion Resistance of a Composite γ-Amino Propyl Triethoxy Silane and γ-Glycidoxy Propyl Trimethoxy Silane Conversion Coating on Galvanized Steel
In an aqueous solution of the mixtures of γ-amino propyl triethoxy silane and γ-glycidoxy propyl trimethoxy silane, a composite silane conversion coating was developed on galvanized steel. FESEM (field emission scanning electron microscope), XPS (X-ray photoelectron spectroscopy), ATR-FTIR (attenuated total reflection Flourier transform infrared spectroscopy) and SST (salt spray test) were used to characterize the obtained composite silane conversion coating and also the coating formation process was studied. The result showed that the surface of the composite silane conversion coating was complete, consecutive and compact. The coating could endure a neutral salt spray test for 72 h without corrosion. The result of salt spray test indicated that the composite silane conversion coating can provide a better corrosion inhibition than the coating which was composed of the single silane. Based on observation and analysis, it was proposed that the formation process of the silane coating on zinc should consist of three steps: the hydrolysis of the silane molecules, silane chemical adsorption and silane crosslinking condensation. The crosslinking reactions took place between γ-amino propyl triethoxy and γ-glycidoxy propyl trimethoxy silane during the forming process of the coating, and a high crosslinked density interpenetrating structure network was obtained, so the composite silane conversion coating could keep the corrosive substances from the zinc more effectively.
2012 Vol. 19 (11): 46-51 [
摘要
] (
1676
) [
HTML
0KB] [
PDF
0KB] (
12
)
52
XIAO Fu-ren,CAO Ya-bin,QIAO Gui-ying,ZHANG Xiao-bing,LIAO Bo
Effect of Nb Solute and NbC Precipitates on Dynamic or Static Recrystallization in Nb Steels
Nb is often considered to be a powerful alloying element for controlling the recrystallization process in microalloyed high strength steels. However, Nb can be presented either as solute in solution, where it is thought to exhibit a strong solute drag effect, or as NbC precipitates, which are thought to be effective at pinning grain boundaries. Therefore, it is very important to quantitatively measure Nb in solution or in NbC precipitates. A quantitative analysis method of Nb in solution and in precipitates was proposed. The test procedure involved chemical dissolution, filtration and inductively coupled plasma atomic emission spectroscopic (ICP-AES) analysis. The amount of Nb in solution in Nb-microallyed steels under different treatment conditions was evaluated. The results show that the niobium and carbon contents in steels have a great effect on niobium dissolution kinetics. The solute Nb is more effective to retard dynamic recrystallization, while the NbC precipitates are more effective to inhibit static recrystallization. The results may help to comprehend effect of Nb in steels, and provide some guides in the design of new high strength Nb-bearing steels.
2012 Vol. 19 (11): 52-56 [
摘要
] (
1499
) [
HTML
0KB] [
PDF
0KB] (
28
)
57
MENG Xian-ming,ZHANG Jun-bao,HAN Wei,ZHAO Jie
Fracture Behavior of Cold Sprayed 304 Stainless Steel Coating During Cold Rolling
The fracture behavior of cold sprayed 304 stainless steel coating in cold rolling process was studied. The 304 stainless steel coatings were deposited on low carbon steel substrate by cold gas dynamic spray (CGDS) and then cold rolled, respectively. The fracture morphology of the coatings was observed and analyzed, and the crack distributions along the longitudinal rolling direction of the coatings were also investigated and discussed. The results showed that the cohesive strength of the cold sprayed 304 stainless steel coating was too low to be cold rolled. Microcracks were formed in the as-sprayed coatings and ran perpendicularly to the rolling direction. The spacing distance between these cracks decreased with the increase of the cold rolling reduction. In addition, it was also found that the initial crack generated at the surface of the coating and propagated from the surface to the interface along the weakly bonded particles. A theoretical analysis was developed for the coating fracture. It gave a critical minimum cohesive bonding strength of the coating for non-breaking in cold rolling process. The crack propagation manner of the cold rolled coatings was also discussed.
2012 Vol. 19 (11): 57-63 [
摘要
] (
1538
) [
HTML
0KB] [
PDF
0KB] (
39
)
64
LI Zhuang,,WU Di,L Wei
Effects of Rolling and Cooling Conditions on Microstructure and Mechanical Properties of Low Carbon Cold Heading Steel
Effects of rolling and cooling conditions on microstructure and mechanical properties of low carbon cold heading steel were investigated on a laboratory hot rolling mill. The results have shown that the mechanical properties of low carbon steels exceed the standard requirements of ML30, ML35, ML40, and ML45 steel, respectively due to thermomechanical controlled processing (TMCP). This is attributed to a significant amount of pearlite and the ferrite-grain refinement. Under the condition of relatively low temperature rolling, the mechanical properties exceed standard requirements of ML45 and ML30 steel after water cooling and air cooling, respectively. Fast cooling which leads to more pearlite and finer ferrite grains is more critical than finish rolling temperatures for low carbon cold heading steel. The specimen at high finish rolling temperature exhibits very good mechanical properties due to fast cooling. This result has great significance not only for energy saving and emission reduction, but also for low-carbon economy, because the goals of the replacement of medium-carbon by low-carbon are achieved with TMCP.
2012 Vol. 19 (11): 64-70 [
摘要
] (
1531
) [
HTML
0KB] [
PDF
0KB] (
25
)
71
S R Elmi Hosseini
Simulation of Case Depth of Cementation Steels According to Fick′s Laws
The carburizing process is the enrichment of the depth of low carbon steels with carbon. It leads to samples with a combination of high surface hardness and high core toughness and to an impact strength that is required for many engineering parts. The material studied is a low carbon steel. The carbon content is little in this type of steel (wC=0.2%). The calculation of case depth is very important for cementation steels that are hardened in the carburizing process. The effective case depth is defined as the perpendicular distance from the surface to a place at which the hardness is HV 550. Nowadays, a great number of studies have been carried out on the simulation of effective case depth, but no studies have been conducted to determine the numerical relation between the total case depth on one hand and the carburizing time and the effective case depth on the other hand. The steel specimens were subjected to graphite powder. Then, they were heat treated at 925 ℃ for about 3, 5, 8 and 12 h, respectively. Then, these parts were quenched in oil. To determine the effective case depth, the microhardness test was performed on the cross-section of specimens. Plotting the case depth vs carburizing time, the required conditions for obtaining the specified case depth were determined. Also, the comparison between the case depths in numerical solution and the actual position in pack carburizing was performed.
2012 Vol. 19 (11): 71-78 [
摘要
] (
1893
) [
HTML
0KB] [
PDF
0KB] (
46
)
钢铁研究学报(英文版)
编辑部公告
·
《钢铁研究学报》第二届青年编委招募
·
《钢铁研究学报》英文版“极端环境下材料的腐蚀和磨损”专刊征稿启事
·
《钢铁研究学报》英文版“钢铁冶金固废资源化利用”专刊征稿启事
·
《钢铁研究学报》英文版“多相多尺度冶金过程数值仿真”专刊征稿启事
·
《钢铁研究学报》英文版“人工智能在钢铁冶金及材料中的应用”专刊征稿启事
更多
作者指南
投稿须知
论文模板
标准规范
版权协议
读者会员登录
友 情 链 接
更多
版权所有 © 《钢铁研究学报(英文版)》编辑部
地址：北京市海淀区学院南路76号 邮政编码：100081
