最新刊期
卷 38 ， 期 2 ， 2017
- 摘要：The tested alloy UNS N06625 (/% : 0.027C, 0.005S, 0.005P, 0.27Si, 0.07Mn, 21.68Cr, 62.93Ni, 9.00Mo, 3.98Nb, 0.20Ti, 1.22Fe, 0.143Al) is melted by a 3t medium frequency induction furnace, remelted by a 3t ESR furnace and forged to products. The tensile test at 950〜1180℃ with deformation rate 5 s-1and the compression test with deformation rate 1, 5 and 10 s-1and true strain 0.9 of alloy UNS N06625 have been earned out by Gleeble 1500D thermal simulator to get the deformation resistance, reduction of area and true stress-strain curves. With analysis on deformation resistance and reduction of area of the alloy, it is defined that the hot-working temperature zone of alloy UNS N06625 is 975〜1180℃ ; the effect of deformation temperature and rate on dynamic recrystallization of the alloy is studied and the peak stress model and the critical deformation model for dynamic recrystallization of alloy UNS N06625 are established by combined calculation of stress and strain data. The production practice of 5t ESR ingot shows that the suitable breakdown temperature of the alloy is 1120 °C.关键词：UNS N06625合金;峰值应力;动态再结晶临界变形量;热成形工艺;加热温度2|0|0更新时间：2026-01-21
- 摘要：The crystallization phenomenon of continuous casting mold flux vitreous membrane in reversion-heating process has important influence on thermal resistance of flux film. The influence of basicitv (R 0.8~1.4) on crystallization rate of casting mold flux (/% ：28.22〜49.73CaO, 35.52SiO24.00Na2O, 2.14MgO, 14.55A12O30.72TiO20.93Fe2O30.32K2O, 0.32MnO22.03CaF26.18C) has been studied by using the SHTT-II melting crystallizing temperature measuring instrument and metallographic microscope to establish the TTT curves, the nucleation activation energy of mold flux with different basicity is calculated and the morphology of surface of mold flux with different basicity reversionheating at 800°C900 °C and 1000 °C is observed. The test results show that with increasing basicity the recrystallization temperature of mold flux and the nucleation activation energy continuously decrease ； with reversion-heating temperature rise of vitreous flux film, the bulges and pits at surface and a mass of defects in inner of film occur. The suitable range of basicity of flux is put forward that is 0.80~0.95 for low carbon steel,≥l.2 for medium-carbon steel and 0.75〜0.90 for high carbon steel.关键词：连铸;结晶器;渣膜;碱度;SHTT热丝法;结晶率2|0|0更新时间：2026-01-21
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Physical Simulation on Optimization of Submerged entry Nozzle for 250 mm x 1800 mm Slab Casting Mold
摘要：With using geometric similarity 1：2 water model, the effect of nozzle structure (lateral holes type, hole dimension and clip angle：S1-rectangle, 6868 mm2-25°； S2- racing way type, 8468 mm2-15°； S3-ellipse, 8011 mm2-15°) , casting speed (0.85~1.05 m/min) and immersion depth 55~75 mm on mold liquid level fluctuation, distribution of flow field and mold flux coverage condition has been studied. Results show that with decreasing dimension and dip angle of lateral holes, the liquid surface wave height increases, as dimension of lateral holes decreases by 5.4% , the wave height increases by about 32.4% ； with increasing casting speed and decreasing immersion depth the wave height increases； and with increasing dimension and dip angle of lateral holes and casting speed the impact depth increases. With present nozzle S2 the fluctuation of liquid level is very small it is unfavorable for melting mold powder and uniformly heal-transferring and with present nozzle S1 the impact depth is too large, it is unavailable to remove inclusions in liquid, but with optimized nozzle S3 the fluctuation of liquid level and impact depth are more reasonable, the flux becomes more active, it is available to melt mold powder and remove inclusions in liquid.关键词：板坯结晶器;水模型;浸入式水口结构;液面波动;流场;保护渣层2|0|0更新时间：2026-01-21 - 摘要：The lime with 260, 401, 397 and 383 mL four kinds of activity is manufactured by calcined limestone. The ingredient of tested slag for desulphurization of hot metal is (/% :) 35.18〜44.84CaO, 13.80〜23.46SiO218.98Al2O39. 49MgO, 1.89Fe2O311.00CaF2with basicity 1.5~3.25, and the chemical composition of hot metal is (/% :) 4.53C, 0.16Si, 0.107S, 0.099P. The tested slag-metal ratio is 7：100 to 15：100 and the desulphurization test is in an induction furnace at 1330〜1390 °C. The sulphur content in metal in crucible is analyzed by a fluorescence analyzer, and the distribution of specific surface area and size of pore of lime are measured by an automate pressure mercury analyzer. The experiment is carried out by a single variable method to study the effect of slag basicity, melting temperature, slag-metal ratio and activity of lime on desulphurization of hot metal. The test results show that the lime with activity 397 mL is larger specific surface area and more uniform pore distribution, it has best desulphurization effect. With slag basicity 2.25, slagmetal ratio 15：100 and at 1390℃, by using lime with activity 397 mL the desulphurization ratio of metal is up to 97.2%.关键词：铁水;脱硫;石灰;活性度3|1|0更新时间：2026-01-21
- 摘要：The metallurgical process flowsheet of 64 mm x 160 mm forged slab of tested steel 14Cr1Mo (/% : 0.12C, 0.57Si, 0.48Mn, 0.003P, 0.001S, 1.20Cr, 0.42Mo, 0.01V, 0.00lNb, 0.017Al, 0.003As, 0.00lSb, 0.002Sn) is 30t EBT EAF-LF-VD-13t casting ingot- forging. With the process measures including using quality scrap, controlling EAF end [P]≤0.002% and end [C]0.07%〜0.10% , adding Al in EAF tapping for pre-deoxidization of liquid, LF maintaining white slag ≥30 min and VD 67 P≥25 min, and after VD adding 0.35 kg/1 Ca-Si wire, the gas content in steel is 1.5 x 10-6[H] , 17 x 10-6[O] and 70 x 10-6[N] , the ratting of each nonmetallic inclusions in steel is 0.5 , and with conditioning treatment at 930℃, A. C. ,quenching at 910°C , W. C. and tempering at 700°C , A. C. , and simulate heat treatment after welding ( PWHT) at 690°C for 4~20h. F. C. , the mechanical properties of steel meets the requirement of reference standard NB/T470008-2010.关键词：Steel 14Cr1Mo;30t EAF-LF-VD;Practice of Process;Inclusions;Mechanical Properties2|0|0更新时间：2026-01-21
- 摘要：The production flowsheet of φ5 mm coil of stainless steel 0Crl3 is 60t AOD-LF-150 mm x 150 mm casting billet-rolling process. By the optimizing processes including increasing the AOD top lance blowing flow rate from (70 + 50) m3/min to (95 +65) m3/min, controlling slag basicity 3.0~4.0 in oxidizing period and end temperature 1670~1710℃ , increasing lime quality, reducing tap to tap time and decreasing carbon pickup in process ； controlling suitable nitrogen-argon switching to properly decrease blowing nitrogen amount and realize in reduction low nitrogen control and argon balance use； and modifying the elliptic taphole to round taphole as a result decreased the tap to tap time from 180 s to 100 s so as to decrease the nitrogen increment in process, the steel 0Cr13 [C] decreases to ≤0.020% form original 0.025% , [N] decreases to ≤0.010% form original 0.020% and the [C+N] is ≤0.035% , and the tensile strength of the wire could control to less than 500 MPa.关键词：60t AOD;Ultra Low [C+N] Stainless Steel 0Cr13;Tensile Strength;Process Practice2|0|0更新时间：2026-01-21
- 摘要：The metallurgical production flowsheet for 0.3〜4.0 mm cold-rolled sheet of 316L stainless steel is 180t EAF-AOD-LF-200 mm casting slab-hot-rolled 2.5~14.0 mm plate-cold rolling process. The analysis on line scale defects occurred on surface of 316L stainless steel cold-rolled sheet has been carried out by chemical composition analysis, metallography ,scanning microscope and energy spectrum examination on casting slab, hot-rolled coil and cold-rolled sheet. Results show that the surface oscillation mark of casting slab is deeper with depressions and there are depth ≤300 μm micro crack defects ； the surface of hot-rolled plate has line defect and there is larger oxidation area around the line defect ； no large size inclusion is found at the defects of cold-rolled sheet (S content 0.001% and Creq(/Nieq= 1.58) , it is obtained that the line scale defects of cold-rolled sheet come from casting stab defects, which are seriously oxidized in heating furnace finally to form the cold-rolled sheet surface line defect. With using the process measures including decreasing slab casting speed from 1. 1 m/min to 1. 0 m/min, reducing overheating extent of liquid from 45℃ to 40℃ , decreasing secondary cooling water rate from 1.0 kg/t to 0.9 kg/t and changing slab grinding wheel from 16# to 20#, the surface defects of cold-rolled sheet decrease markedly.关键词：316L Stainless Steel;Casting Slab;Line Defect;Cold-Rolled Sheet;Surface Crack;Process Improvement2|0|0更新时间：2026-01-21
- 摘要：The main reason of low fatigue life of steel 60Si2MnA for auto stabilizing rod (/% : 0.56C, 1.74Si, 0.74Mn, 0.011P, 0.007S, 0.04Cr) is analyzed by using optical microscope, scanning electron microscope and energy dispersive spectrometer, i. e. the decarburized layer is deeper, there are cracks at surface of steel rod and the quenched structure has a lot of ferrite. With the process measures including adding 0.22% Cr in steel, adding procedure of grinding on while surface of billet and decreasing heating temperature of 150 mm x 150 mm casting billet from original 1130~1150 ℃ to 1080~1100℃ , the ferrite content in quenched steel decreases obviously, there is no crack defect on surface of steel bar and the total decarburized layer depth of φ18 mm bar decreases from original 128 μm to 87.5 μm, as a results the fatigue life of the steel increases form 6 x 104~10 x 104to 20 x 104~25 X 104to meet the requirement of design.关键词：Sled 60Si2MnA for Stabilizing Rod;Suiface Quality;Decarburized Layer;Ferrite;Fatigue Life;Process Optimization2|0|0更新时间：2026-01-21
- 摘要：The depressed defects of scales with dimension (10~40) mm x (3~10) mm and depth 1~3 mm occur at 30 mm plate hot-rolled from 230 mm casting slab of steel Q235B (/% : 0.18C, 0.20Si, 0.34Mn, 0.015P, 0.005S, 0.07Cr). The primary scale formation mechanism and removability at high temperature in high-pressure water descaling operation are analyzed and the measures to optimize the process are forward including (1) with optimizing heating process to insure the casting slab surface temperature being more than 1170 °C for high-pressure water descaling； (2) with optimized high-pressure water parameters i. e. increasing spray-water pressure from 18 MPa to 20 MPa and flow velocity from 161.2 m/s to 170.0 m/s, in order to increasing the impact force from 116.3 N to 122.7 N. The test and commercial production results by 26 heats show that after process optimization the closing off rate of slab caused by rolled-in scales reduces to less than 2% , it is obvious to improve the rolled-in scales defects.关键词：Steel Q235B;Heavy and Medium Plate;Primary Scales;High-Pressure Water Descaling;Removability3|1|0更新时间：2026-01-21
- 摘要：The tested steel LY225 (/% : 0.07C, 0.05Si, 0.50Mn, 0.007P, 0.008S, 0.0050N) is melted by a 500 kg vacuum induction furnace, cast to 210 mm slab and rolled to 25 mm and 40 mm plate, finishing temperature 790~830℃ water cooling. The structure of LY225 steel plate normalized heated at 880~900℃ , air cooling is polygonal ferrite with grain size rating 7.5~8.5, yield strength 225~234 MPa, impact energy at 0℃ 285~294 J, and has better high- strain low-cycle fatigue property and weldability to meet the requirement of GB/T28905-2012 for mechanical properties of low yield point steel LY225 for anti-seismic building.关键词：Steel LY225 for Anti-Seismic Building;Low Yield Point;Mechanical Properties;Polygonal Ferrite;Development8|0|0更新时间：2026-01-21
- 摘要：The bottom blowing argon is carried out in commercial production of 40 heats 120t BOF steelmaking process, at blowing 15% the C content in metal is 4.0% with slag ingredient (/%) ： 21.2FeO, 2.6A12O35.3MnO, 31.2CaO, 11.2MgO, 23.7SiO23.2P2O5and basicity 1.3, and at end blowing the C content in liquid is 0.1% with slag ingredient (/%) : 14.5FeO, 2.0Al2O33.9MnO, 49.5CaO, 8.0MgO, 13.5SiO22.2P2O5and basicity 3.4. The effect of slag foaming level on removal of nitrogen in BOF liquid is studied by gas and composition analysis and optical microscope ,and the mechanism of secondary removal of nitrogen in slag is discussed. The analysis results show that in earlier blowing period the removal of nitrogen in BOF metal is weaker, the removal of nitrogen is concentrated in 15%~80% blowing process, in last period of BOF blowing the liquid has some nitrogen increment. As the metal droplets exist in slag, the slag foaming level is better and the retained time of CO in slag is longer to increase the change of collision between CO bubbles and metal droplets, the effect of secondary removal of nitrogen is obvious. With N content in charging metal being 53 x 10-6with regard to heats with better slag foaming level the BOF end N content average in liquid is 13.7 x 10-6and the average removal rate of nitrogen reaches 74.2% , while to heats with lower foaming level the BOF end N content average in liquid is 25.2 x 10-6and the average removal rate of nitrogen in liquid is only 52.5%.关键词：120t BOF;Foaming Slag;Removal Nitrogen in Liquid;Secondary Removal of Nitrogen in Liquid2|0|0更新时间：2026-01-21
- 摘要：The production flowsheet for V-Nb-Ti microalloying S355NL large size seamless tube for low-temperature structure (/% ： 0.14~0.15C, 0.29~0.30Si, 1.35〜1.37Mn, ≤0.014P, ≤0.005S, 0.02~0.03Nb, 0.06~0.07V, 0.010~0.020Ti, 0.39~0.41 Ceq)is 100t EAF-LF-VD-feeding Ca wire-φ400 mm round bloom casting- 3-roll mill trainnormalizing treatment at 940 °C for 30 min, air cooling. The statistic results of 16 heats and batches show that with the process measures including adding silicon -manganese and fenrrosilico-aluminium alloy in tapping of EAF, using CaO-SiO2- Al2O3slag series and whole process argon blowing in LF refining, VD treating for 20~25 min, using long nozzle and argon blowing in casting process, the object quality and properties of steel tube are constant with uniform structure and fine grains, and the each property index meets or exceeds the technical requirement of standard and the purchaser, i. e. yield strength ReH380~435 MPa, tensile strength Rm522~605 MPa, elongation A 24%~29% and impact energy at -50℃ 132~237 J.关键词：100t EAF-LF-VD-Round Bloom CC Flowsheet;φ406 mm x 15 mm S355NL Steel Tube;-50℃;V-Nb-Ti Microalloying;Normalizing Treatment3|0|0更新时间：2026-01-21
- 摘要：The metallurgical flowsheet of 160 angle steel Q420C with 18 mm thickness for power tower (/% : ≤0.20C, 1.00〜1.70Mn, ≤0.55Si, ≤0.035S, ≤0.035P, 0.02~0.20V, ≥0.015Als) is 80 t BOF-LF-CC-rolling process. The analysis on comer cracks of hot-rolled angle steel is carried out by optical microscope, scanning electron microscope and energy dispersive spectroscopy. The results show that there are decarburized layer and ferrite film around cracks, the S enrichment near cracks and the AIN precipitates at grain boundary are found that break the continuity of steel matrix. It is obtained that the slag inclusions at oscillation mark bottom, segregation, thermal stress and bending straightening stress lead to angle steel crack along grain boundary. With process measures including decreasing [N] to 0.0080% , controlling Als 0.017%~0.022% , [Mn]/[S] ≥80, liquid over heating extent ≤25°C , viscosity of mold powder 0.73 Pa·s, and straightening temperature ≥950°C , the quality cast billet increases to 85% from original 25.78% , it is available to decrease the occurrence of comer cracks of angle steel.关键词：Steel Q420C;180 mm x 180 mm Cast Billet;Angle Steel;Segregation;AIN;Corner Cracks2|0|0更新时间：2026-01-21
- 摘要：The production flowsheet of tested 280 mm x 325 mm casting bloom of steel ML20Cr is 80t top and bottom combined blowing converter-LF-CC process. The hot ductility curves of casting bloom of tested steel at 650~1200 °C are measured by Gleeble 1500 hot simulator, and the effect of adding 0.029Ti-0.0023 B on hot ductility of steel MLCr20 (/% : 0.2i〜0.22C, 0.22~0.23Si, 0.74〜0.76Mn, 0.015~0.017P, 0.002〜0.003S, 0.95〜0.96Cr, 0.034~0.036 Al, 0.0050~0.0051N) is analyzed. Results show that in 650~ 900℃ the plasticity of steel ML20Cr containing 0.029Ti-0.0023B ( reduction of area ＞70% at 750℃) is better that of steel ML20Cr un-adding Ti-B ( reduction of area ＜50% at 750°C ). The main reason is that the prior precipitated TiN decreases the effect of fine AIN in No Ⅲ brittle zone, and the B segregate at austenite grain boundary to inhibit the formation of proeutectoid ferrite thin film, in order to effectively improve the hot ductility of steel. The commercial production results show that with adding micro Ti-B tn steel ML20Cr the cracking j-ate of casting bloom decreases from 3.7% to 0.3% .关键词：Cold Heading Steel ML20Cr;Ti-B Microalloying;280 mm x 325 mm Casting Bloom;Hot Ductility2|0|0更新时间：2026-01-21
- 摘要：The 20 mm clad plate of surface-treated 10 mm plate of low alloy wear-resistant NM450D steel (/% : 0.22C, 0.70Cr, 1.50Mn, 0.30Si, 0.012Ti, 0.030Nb) and 10 mm plate of carbon steel Q235B (/% ： 0.19C, 0.25Mn, 0.04Si) is welded at four-comer of plate and double-rolled by a lab 180 mm two-high mill with reduction 60% at 1150℃ and with reduction 30% at 930°C to 5.6 mm clad plate, then quenched at 800~1000°C and tempered at 250 °C. Results show that the clad interface of 5.6 mm clad plate of low alloy wear-resistant steel-carbon steel quenched at 900°C + tempered at 250°C has nice contact, the structure of steel Q235 is lath martensite + ferrite and minor bainite and pearlite, the structure of steel NM450D is tempered martensite with HV hardness value 500, the shearing-strength of clad plate is 367 MPa, all meet the requirement of standard.关键词：Wear-Resistant Steel NM450D-Carbon Steel Q235B Clad Plate;Clad Interface;Control-Rolling;Heat Treatment;Structure;Shearing Strength2|0|0更新时间：2026-01-21
- 摘要：The metallurgical flow sheet of tested pipeline steel X52 (/% : 0.070~0.0790, 0.22Si, 1.29~1.32Mn, 0.008~0.009P, 0.002S, 0.028Al, 0.0016~0.0017T[O], 0.0053〜0.0065N) is hot-metal pretreatment- 220t BOF-LF-VD-230 mm slab CC. The main steelmaking processes are adding aluminium shot in tapping of BOF； main ingredient of LF refining slag- (/%) : 54.41~58.54CaO, 7.66~8.42SiO222.57~24.69A12O34.15〜4.58MgO, 0.78~2.89FeO ； and feeding calcium wire treatment after VD. The evolution of inclusions in steel during steelmaking process is studied by auto scanning electron microscope with ASPEX ( Application Specific Products employing Electron Beam and X-ray technology). Results show that before LF refining the inclusions in liquid are AI2O3 cluster and granule, after LF refining the Al2O3is modified to globular CaO-MgO-Al2O3inclusion, then modified to globular CaO-Al2O3-CaS inclusion after calcium treatment; by VD treatment the number of inclusions in liquid decreases from 30〜35/mm2to 7~15/ mm2and the T[O] and [N] markedly decrease to 12 x 10-6~13 x 10-6and 41 x 10-6~48 X 10-6. from end soft stirring to tundish the number of inclusions in liquid dramatically increases to 33/mm2at end VD the average size of inclusions is up to maximum i. e. 2.6~3.6 μm, but in tundish that decreases to 1.9~2.1 μm: during feeding wire and soft blowing process the T[O] and [N] increase to some extent, it shows that the secondary oxidation of liquid occurs； with LF refining, VD and calcium treatment the S content in steel decreases lo 16 x 10 ; and the high (SiO2) and ( FeO + MnO) content in tundish shielding flux lead to resulfurization of liquid in tundish.关键词：X52 Pipeline Steel;Al2O3;CaO-MgO- Al2O3;CaO- Al2O3-CaS;ASPEX;Cleanliness2|0|0更新时间：2026-01-21
- 摘要：The hot compression test on 4>5 mm x 86 mm test specimen cut from 80 mm hot-rolled plate of steel EH460 (/% ： 0.07C, 0.39Si, 1.76Mn, 0.34Ni, 0.36Cu, 0.02〜0.05Nb, 0.05~0.10V, ≤0.02Ti, 0.008Als) with 10℃/s heating to 1200 ℃for 5 min austenizing then with 10°C/s cooling to 830 °C and with strain rate 1 s-1deformation 30% at 830°C,then cooling to ambient temperature with 1~30°C/s has been carried out by using a Gleeble-3800 thermal simulation testing machine. And the dynamic continuous cooling transfonnation (CCT) curves of tested steel EH460 is obtained by dilation-temperature curves combined with structure at different cooling rate and using Origin software. Results show that with cooling rate less than 3 °C/s the structure of steel EH460 is ferrite + minor bainite, with cooling rate 5~10°C/s the structure is bainite + minor ferrite and with cooling rate more than 20 °C/s the structure is mainly lath bainite with little granular bainite ； with cooling rate increasing from 1 °C/s to 30 °C/s the HV hardness value of the steel increases form 246 to 274.关键词：Hull Structure Steel EH460;Phase Transformation;Cooling Rate;CCT Curves2|0|0更新时间：2026-01-21
- 摘要：The rolling flow sheet for tested oriented silicon steel cold-rolled sheet (/% : 0.050C, 3.20Si, 0.15Mn, 0.003S, 0.023Als, 0.0090N) is 220 mm cast slab-hot rolled to 1.8 mm plate-normalized at 1120℃. for 2.4 min- cold- rolled to 0.23 min and 0.18 mm sheet, then decarburized at 850℃ for 5 min and nitriding at 700°C for 2 min, after treated the C content in sheet is 0.0020% and the N content in sheet is 0.0180% . The effect of N2content (25% , 50% , 75% and 90% ) in atmosphere during 17℃/h annealing heating up period at 600~1200 ℃ on magnetic performance of 0.23 mm and 0.18 mm cold-rolled sheet of low-temperature heating oriented silicon steel has been tested and studied. Results show that during 600〜1200℃ heating up period with using 50% N2and 75%N2atmosphere the 0.23 mm sheet of low-temperature heating oriented silicon steel has better magnetic performance, its iron loss is 0.9 W/kg, and with using 75%N2atmosphere the 0.18 mm sheet of low-temperature heating oriented silicon steel has optimum magnetic performance, its iron loss is 0.8 W/kg, and with using 25% N2the magnetic performance of 0.18 mm sheet is poorest i. e. iron loss 1.63 W/kg关键词：Low-Temperature Heating Oriented Silicon Steel;Cold-Rolled Sheet;Atmosphere of High-Temperature Annealing;Magnetic Performance2|0|0更新时间：2026-01-21
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