最新刊期
卷 41 ， 期 5 ， 2020
- 摘要：In order to study the effect of soaking process in critical zone of Q&P ( Queching and Partition) steel on the cementite precipitation during partitioning process, the PTT ( precipitation amount-temperature-time) curves of the cementite precipitation of steel Q&P are calculated by Avrami dynamic equation. Q&P steel is annealed in single phase zone and critical zone,and quenched after annealing by thermal dilatometer, the carbon content of martensite is calculated by measuring the diffraction spot of room temperature martensite with transmission electron microscopy to predict the carbon content of high temperature austenite. Different critical annealing Q&P process conditions are simulated by continuous annealing simulate machine. The size of precipitated cementite is measured by scanning electron microscopy. Combining heat treatment process and maturity rate of cementite, the starting time of precipitation is calculated. The absolute position of the 5% cementite precipitated volume fraction PTT curve is obtained. At the soaking condition of 846 °C , the nose temperature is 300 °C. At the condition of soaking at 811°Cthe nose temperature rises to 325 °C , and at the condition of soaking at 764 °C , the nose temperature rises to 400 °C. The precipitation of cementite can be avoided when the partition time is ≤450 s at the condition of soaking at 746 ~ 846°C关键词：Q&P Steel, Annealing in Critical Zone, Partitioning Process, Cementite;Precipitation, PTT2|0|0更新时间：2026-01-21
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Research Progress on the Preparation of Bimetallic Composite Roll by Electroslag Cladding Technology
摘要：The composite roll is a kind of bimetallic composite material which consists of a high wear-resistance mate¬rial as the working layer and a high strength, toughness material as the core respectively. In this paper, a systematical introduction is given for the preparation of bimetallic composite roll by electroslag metallurgy technology including ESR clad¬ding method, electroslag surfacing by liquid metal and consumable mold cladding method at home and abroad. The influence of consumable electrode form, conductive circuit scheme, supply method of the outer metal and equipment structure on the bimetallic cladding process and the comprehensive performance of composite roll are analyzed. At the same time, the basic process characteristics and control keys technology of the different methods are summarised. Based on the analyses of the development history of electroslag cladding technology and the stability control of composite roll performance, the future prospect and development of the preparation of bimetallic composite roll by electroslag cladding method is prospected.6|0|0更新时间：2026-01-21 - 摘要：Based on prototype of steelworks 40t LF, by using the generalized similarity principle, experimental study on the 1:3 water simulation has been carried out. According to Buckingham's π theorem, a characteristic number equation model to describe the effect of mixing molten steel in bottom argon ladle is obtained. Through regression analysis of experimental data, a fitting equation to express mixing effect of stirred liquid in geometric similarity ladle is got. At the same time, the ANSYS CFX software is used to verify the optimal blowing position of the original blowhole and double blowholes. The result of experiment shows that with the argon bubbling at 2/3R distance from the center of bottom and using a single purging plug, the active zone of the ladle is largest and the stirring mixing time is the shortest.关键词： Ladle Refining, Water Model, Influencing Factor2|0|0更新时间：2026-01-21
- 摘要：The production flowsheet of 20 Cr steel is 120 t BOF-LF-200 mm x200 mm bloom CC-rolling. The composition detection, metallographic analysis and SEM energy dispersive analysis on the scarring and warping of forged small mechenical crankshaft of Φ35mm 20Cr round steel are carried out. The results show that during the continuous casting process,the mold liquid level fluctuation exceeded ±5 mm,led to mold powder to enter the meniscus,causing slag inclusion and carburization on the surface of the bloom, finally forming scarring and warping defects during rolling. By increasing the depth of the submerged nozzle form 80 ~ 120 mm to 90 - 130 mm, strengthening the control of the tundish nozzle and stop¬per, and optimizing the operation and performance of mold powder, the liquid level fluctuation in mold is stable within ± 3 mm,to avoid entrapped slag and forgings warping.关键词：圆钢;曲轴;翘皮;保护渣;增碳2|0|0更新时间：2026-01-21
- 摘要：After quenching and tempering, straightening and grinding, the surface cracks are found on the polished rod surface of steel 40Crl0Si2Mo 6. 5 mm wire rod. Through the simulation test of quenching and tempering of steel 40Crl0Si2Mo, it is obtained that the reason for the surface crack of steel 40Crl0Si2Mo wire rod is the short cooling time after hot rolling, the cooling speed is fast, and there is a large residual stress on the surface of the hot rolled wire rod leading to form the surface crack. The production process of steel 40Crl0Si2Mo is optimized and improved, including prolonging Stelmo roller slow cooling time, adjusting the finishing rolling temperature and lay-off temperature from 900 ~ 950 °C and 850 〜900 °C to 800 〜850 °C ,and within 24 hours after rolling to anneal the wire, the surface crack of steel 40Crl0Si2Mo product has been avoided.关键词：马氏体气阀钢;40Crl0Si2Mo;应力裂纹;冷却工艺2|0|0更新时间：2026-01-21
- 摘要：The Corner crack of Nb bearing steel HRB400NB 180 mm x 180 mm billet has been studied and analyzed.The results show that improper control of continuous casting cooling process, nitrogen content in molten steel and mold flux can easily lead to corner cracking of Nb bearing billet along grain boundary. With process improvement measures including decreasing the nitrogen content in liquid from original (67 ~ 98) x 10-6to (40 〜55) x 10-6adjusting the arc radius at the corner of mould from 8 mm to 12 mm, decreasing the cooling water quantity of the mould from 150 m3/h to 120 m3/h, decreasing the water ratio of the secondary cooling from 1. 35 L/kg to 1. I L/kg and adjusting the partitioning ratio of secondary cooling from 26： 48： 17： 9 to 36： 34: 19: 11, adjusting the basicity of the mould flux from 0. 65 to 0. 82 , the viscosity from 1.3 pa • s to 0. 69 pa • s, and adjusting the melting point of shielding slag from 1260 °C to 1150 °C. The defects of corner cracks on the surface of billet are effectively solved and the quality of the products is guaranteed.关键词： Nb Steel, Mould, N Content, Casting Billet, Corner Crack 2|0|0更新时间：2026-01-21
- 摘要：Aiming at the problems such as difficult melting of slag and low dephosphorization rate at the early stage of steelmaking high carbon steel in 100 t BOF （ basic oxygen furnace） with titanium-bearing hot metal, the slagging process and the slag physical characters of BOF steelmaking with titanium-bearing hot metal are analyzed, the technology of heel slag + single slag is developed,:, e. The terminal slag is recycled to use,to full play the character of high FeO content of 10% 〜13% FeO in the terminal slag, the CaO-TiO2-SiO2ternaiy slag system in the early stage of steelmaking of titanium-bearing hot metal is rapidly converted into the Ca0-TiO2-SiO2-FeO quaternary slag system, so that most of phosphorus in steel is removed. The basicity of terminal slag is controlled to be more than 3. 2 , the TiO2content in terminal slag is controlled to be less than 5% ,the BOF tapping [C]≥0.20% and tapping [P]≤0.014% , the dephosphorization rate of steelmaking in BOF reaches to 88% 〜92% ,and the consumption of lime decreases to 28 kg per ton of steel.2|0|0更新时间：2026-01-21
- 摘要：The arc slag retaining wall in tundish at Xingsteel is optimized and the process of double slag retaining walls is introduced. The numerical simulation of the double slag retaining walls in tundish is carried out before use, and it is found that the double slag retaining walls are beneficial to control inclusions. The production data of 148 heats with using double slag walls in tundish show that the max rating of B inclusions deceases from 3. 0 to 0. 5 ；that of D inclusions decreases from 1.5 to 0.5 ；and that of Ds inclusion decreases from 3. 0 to 0. 5 ； the unqualified rate of inclusion decreases from 7.67% to 0.关键词：冷镦钢;数值模拟;夹杂物;中间包;双档渣墙;工艺实践7|0|0更新时间：2026-01-21
- 摘要：The production flowsheet of BTQ001 steel is 230 mm cast slab-2.3 mm hot rolled plate-0.63 mm first cold rolled sheet-850 °C annealing-0. 27 mm second cold rolled sheet-1200°C annealing, the changes of microstructure of the products in each phase are analyzed, and the magnetic properties of the finished products of oriented silicon steel are statistically analyzed. The experimental results show that the BTQ001 oriented silicon steel optimum production process is to control the heating temperature at 1280 ~ 1300 °C for hot rolling, the finishing rolling at 950 °C and coiling at 550 °C.2|0|0更新时间：2026-01-21
- 摘要：Through the practice show that, it can be seen the production of bearing steel, the converter tapping temperature ≥1650℃, tapping oxygen ≤300 x 10-6and 18 kg/t slag can achieve 50% desulfurization efficiency in the tapping process. At the same time, the mode of u slag retaining cone + slide plate slag retaining" is adopted in converter tapping to reduce sulfur by another 0. 000 5% ； the mode of aluminum adding in BOF tapping + LF refining to deoxidize with ferrosilicon powder and controlling the binary basicity of slag to be 5 ~ 6 can achieve more than 50% desulfurization effect and stabilize the casting performance to get finished product sulfur content ≤0.0015% .2|0|0更新时间：2026-01-21
- 摘要：Based on dynamics and thermodynamics analysis on the current refining slag system (/% ：4 ~ 17SiO217 ~ 34A12O340 〜65CaO) of the 20 steel-tube produced at Electric Furnace Plant, Zenith Steel Group Co, the refining slag system (/% ：6 ~ 15SiO2,24 ~ 34A12O358 ~ 65CaO) for LF is designed, to ensure the appropriate slag viscosity 1. 5 ~ 2. 0 Pa , s and higher ability to sorb inclusions. The experimental results show that the slag system can well meet the quality requirements of 20 steel tube and can achieve the purpose to remove inclusions in steel with B type inclusion rating ≤1.0.3|0|0更新时间：2026-01-21
- 摘要：Using expansion instrument combined with metallographic analysis and hardness measurement, a continuous cooling transformation (CCT) curves of new Nb-V microalloyed bainite rail steel 20 mm plate (/% ：0. 24C,0. 39Si, 1. 86Mn,0. 007S,0. 002P, 1 • 36Cr,0. 33Mo,0. 04Nb,0. 11V) are determined, the effect of cooling rate 0. 04 〜4. 0 °C/a on microstructure and hardness of steel are studied. The results show that the Bs point of tests steel is lower than 400 °C , when the cooling rate is in the range of 0. 1 to 0. 8 Y/s, the whole bainite structure can be obtained, which is consistent with the bainite rail alloy design principle ； the rolled microstructure of test steel is lath bainite and a small amount of martensite. The strength, plasticity, toughness and hardness of the rolled state are well matched, which meets the relevant technical conditions of the current bainitic rail production.关键词： Nl)-V Micro-Alloying Bainite Steel, Rail, Static CCT Curve, Microstructure, Mechanical Properties 2|1|0更新时间：2026-01-21
- 摘要：The production process of Φ200 mm steel AISI 410SS is 20 t EAF-LF-VD-3 t ingot-forging. Through comprehensive analysis on the micro-morphology and formation mechanism of centre intergranular cracks, it is found that slow cooling of the central part of the liquid steel during solidification results in composition segregation, increasing ferrite formation and inclusion clustering finally led to forgings axis intergranular cracks. By adjusting the composition, increasing austenite-forming elements from original 0.11C-0.16Ni~0.55Mn to 0.14C-0.45Ni-0.78Mn and reducing ferrite-forming elements from original 12.84Cr-0.46S1-0.20Mo-0.022Nl)to 11.81Cr-0.31 Si-0.l0Mo-O.005Nb, the ferrite in steel decreases from original 4% to 0. 5% and the axis intergranular crack rating decreases for 0.5 rating to 0.关键词：AISI 410SS钢;轴心品间裂;铁素体2|0|0更新时间：2026-01-21
- 摘要：The high temperature tensile test and microstructure characterization of 0.10C5Mn2Al steel with strain rates 10-2/s at 750 ~ 850 ℃ are carried out. The results show that the elongation of 0.10C5Mn2AI steel strain rate 10-2/s at 750 °C ,800 °C and 850 ℃ is 320% ,570% and 730% respectively to obtain superplasticity. In the process of superplastic deformation, both austenite and ferrite grains grow due to the combination of deformation and high temperature and the reformation is the main cause of grain growth.关键词：冷轧中锰钢;超塑性;高温拉伸;高应变速率2|0|0更新时间：2026-01-21
- 摘要：The microstructures and textures in final products of the non-oriented silicon steel(0.003% C,0.80% Si, 0. 28%Mn,0. 015%P,0. 003%S,0. 24% Als) with different cold bending process and stress-relief annealing at 750 °C for 2h are determined and analyzed. The results show that the preferred nucleation and preferred growth of new grains at surface in stresrelief annealing strongly reduce the detrimental {111} texture, particularly the {111}<112> texture component is not predominant and the beneficial Goss texture of ({110}<001>) is promoted. The proposed bending 20 times working process can improve both formability and magnetic properties of stress relief annealed sheet products.2|0|0更新时间：2026-01-21
- 摘要：The effect of single roll soft reduction (0〜14 mm) and reduction position ( 1#~ 7#) on inacrostructure and central carbon segregation of 240 mm x 240 mm casting bloom of low carbon steel 20CrMnTiH has been tested and studied. Results show that as from roll No. 3 reduction and maximum soft reduction 9 mm, the ratio of the without shrinkage cavity increases by 12.3% and the ratio of center porosity 1.0 rating and center carbon segregation do not improve obviously ；as from roll No. 2 reduction with maximum soft reduction 1 1 mm, the ratios of center porosity 1.0 rating and the without shrinkage cavity decrease, and the ratio of center carbon segregation increases by 14. 2% ； as from roll No. 1 reduction and the maximum soft reduction 14 mm, the ratios of center porosity 1.0 rating and without shrinkage cavity are up to 100% , and the ratio of center carbon segregation is 71.4% . By comprehensive analysis it is obtained that with casting speed 0.85 m/min, mold stirring 300 A and 5 Hz, the central carbon segregation and macrostructure of steel 20CrMnTiH 240 mm x 240 mm casting billet are better by single roll soft reduction 14 mm.4|0|0更新时间：2026-01-21
- 摘要：Through different heat treatment processes：800、820 ℃ low temperature quenching + 600℃ tempering、 880 °C +860 °C twice quenching + 600℃ tempering and 860 °C once quenching + 600 °C tempering,the heat treatment experiment on 40CrMnMo steel has been carried out to study the effects of three kinds of heat treatment processes on the microstructure and properties of the 40CrMnMo steel. The results show that the tensile strength of tested steel by the three kinds of heat treatment processes is similar (936 ~951 MPa) ,and the microstructures is tempered martensite + ferrite,the impact energy of tested steel of (800、820 °C ) low temperature quenching and 600 °C tempering heat treatment processes is highest (65 ~69 J).2|0|0更新时间：2026-01-21
- 摘要：The production flow sheet of SCM435 steel is 80 t BOF-LF-RH-280 mm x 325 mm bloom casting. LF end refining slag composition is (/% ：) 45 〜55 CaO, 10 〜15SiO220 〜30 Al2O3∑(FeO + MnO) ≤ 1 % . The effect of RH adding calcium (0.0013% Ca) and RH non-adding calcium (0. 0002% Ca) on D and Ds inclusion in Φ13 mm coil is analyzed. The results show that, the inclusion maximum size in steel with RH non-adding calcium treatment process is 7.65 μm,the pass rate of Ds≤0.5 is 100% ,and that with the RH ading calcium treatment process is 25.68μmand the pass rate of Ds≤0.5 is 95%. The inclusion index of non-adding calcium treatment process decreases from original RH adding calcium process 0. 72 to 0. 68 and pass rate of D≤1.0increases from original RH adding calcium process 30% to 75% . With non-ackling calcium treatment process the inclusions are mainly MgO·Al2O3? and a small amount of Calcium aluminate ,and with RH adding calsium process the inclusions are magnesium-alumina spinel, calcium aluminate and CaS heterogeneous inclusions. Therefore,in terms of size,quantity and type control of inclusions of brittle D and Ds, the improvement of RH non-adding Calcium treatment is obvious.关键词：SCM435, 冷镦钢, 夹杂物;不加钙处理工艺2|0|0更新时间：2026-01-21
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