最新刊期
卷 39 ， 期 2 ， 2018
- 摘要：The effect of gas flow rate (0 - 10 L/min) and nozzle bottom shape ( concave bottom and pyramid bottom) on flow field in mold has been studied by using 1: 1 water model. In condition of mold section 230 mm x 1 200 mm and casting speed 1. 6 m/min the fluid pattern in mold with using concave bottom nozzle is better than that with using pyramid bottom nozzle ； and the stability of liquid level in mold with using concave bottom nozzle is also better than that with using pyramid bottom nozzle; with gas flow rate 0 〜8 L/min, the liquid surface velocity with using pyramid bottom nozzle is obviously higher than that with using concave bottom nozzle ； for using concave bottom nozzle as gas flow rate is larger than 8 L/min, its surface velocity is lower than 0. 2 m/s； 120 heats IF steel commercial production results show that using optimized concave bottom nozzle with argon flow rate 7 L/min the fluctuation of surface of liquid in mold during casting precess is within ± 3 mm, and compared with before optimization the inclusions amount in casting slab decreases by 24%.2|0|0更新时间：2026-01-21
- 摘要：The tested steel 0. 05C-14Mn-19Cr-0. 7N is melted by 1 t non vacuum induction furnace and remelted to ESR ingot. By sampling at center of ESR ingot and using Gleeble 3800 thermo-simulation testing machine the thenno tensile examination of tested steel at 800 ~ 1250°Cwith strain rate 0. 005 ~ 10 s-1has been carried out to get the effect of temperature and strain rate on reduction of area of tested steel, and the structure of steel tensile-tested at each temperature is observed. Examination results show that with temperature increasing from 800 ℃ to 1 250 ℃ the tensile strength of tested steel decreases from 327 MPa to 68 MPa and the reduction of area of steel increases from 22% to 55% ；at 1200℃,with strain rate increasing from 0. 01 s-1to 10 s-1 the tensile strength of tested steel increases from 43 MPa to 109 MPa and the reduction of area of steel increases from 38% to 71%. Integrating the experimental results it is obtained that the optimized deformation parameters for high nitrogen austenite stainless steel 0. 05C-14Mn-19Cr-0.7N are rolling at 1200 ~ 1250°Cwith stain rate 1 ~ 10s-1.4|0|0更新时间：2026-01-21
- 摘要：With using Gleeble-3500 thermal simulator the single pass hot compression deformation and structure evolution of 20 mm hot-rolled plate of 700 MPa pipeline steel (/%: 0.07C, 0.90Si, 0.60Mn, 0.008P, 0.002S, 0.30Ni, 0.10Cr, 0.12Mo, 0.06V, 0.03Nb, 0.28Cu, 0.04Alt, 0.0060N) with strain rate0.01~1s-1at 850~1250°C have been studied to get single pass real stress-strain curves, hot compression dynamic recrystallization diagram and relation between dynamic recrystallization initial time and deformation temperature (RTT) curves. Research results show that deformation temperature and strain rate make certain of initial recrystallization, the 700 MPa pipe line steel easily occurs dynamic recrystallization with strain rate0.01~1s-1at 1100~1250°C.the recrystallization mechanism is hot compression causing the original grain crushing and the new grain boundary migrating to prompt formation of new crystal nucleus.关键词：700MPa管线钢;20mm热轧板;再结晶;热压缩5|0|0更新时间：2026-01-21
- 摘要：The effect of channel filter on fluid field of liquid in a 58t tundish has been studied by using geometric similarity 0.29 : 1 water model to test liquid flow by both control flow devices- turbulence controller + retaining wall + dam and turbulence controller + retaining wall + channel filter. Results show that in original tundish with turbulence controller + retaining wall + dam the plug flow area is relatively small and the dead area is up to 29.53% , while in optimized tundish adding channel filter with turbulence controller + retaining wall + channel filter the short circuit flow basically disappears, the real resident time of liquid increases and the dead area decreases from original 29.53% to 13.52%. The results of commercial production with 50t tundish, casting 230mm x 1100mm slab and casting speed 1.25~1.30 m/min show that after using channel filter the size of inclusions in liquid at casting area in tundish is obvious less than that in impact zone, the T[O] in liquid at casting area in tundish decreases from original关键词：58t中间包;通道式过滤器;水模型;流场;夹杂物2|0|0更新时间：2026-01-21
- 摘要：The production process flowsheet of grinding ball steel B2 (/%: 0.75~0.85C, 0.70~0.90Mn, ≤0.030P, ≤0.030S, 0.40~0.60Cr, ≤0.20Ni, ≤0.20Cu, 0.010~0.060Al) is 120t BOF-LF-VD-180mmx220mm/260mmx300mm billet CC. With controlling BOF lance level and oxygen supplying rate, BOF heeling slag amount and optimizing bottom blown rate, and BOF full aluminium deoxidation； increasing LF refining slag basicity from 3.44 to 4.25, controlling VD process argon flow rate and soft blown ≥ 15min after VD ； in casting process with using integral stopper package in laddie, full shielding casting operation and liquid overheating extent 10~ 25℃, using special shielding slag for grinding ball steel and mold electromagnetic stirring 320A, 4Hz and finishing electromagnetic stirring 300A, 10Hz, the internal quality of slab of grinding ball steel is improved and each index of steel products meets the requirement.2|0|0更新时间：2026-01-21
- 摘要：The effect of factors including increasing phosphorus content in liquid, aluminium content in liquid, refining slag binary basicity, and Al2O3content in refining slag on increasing silicon content in liquid of low silicon steel ST30A1 (/%: 0.06~0.10C, ≤0.05Si, 0.30~0.45Mn, ≤0.015P, ≤0.005S, 0.025~0.050Al) during LF refining process has been analyzed. It is obtained that the BOF tapping slag amount, liquid aluminium content and refining slag binary basicity are main factors to aflect the increasing silicon content in liquid. With controlling BOF tapping slag amount, decreasing silicon content in raw and auxiliary materials, adjusting the SiO2and Al2O3content in refining slag to control refining slag binary basicity-14 and Al2O3content in refining slag-27%, and controlling aluminium content in liquid 0.010%~0.020%, The increasing silicon content in LF liquid decreases from original 0.033%~0.047% to 0.004%~0.018%.关键词：低硅钢ST30Al;LF精炼;增硅;精炼渣;硅含量控制4|0|0更新时间：2026-01-21
- 摘要：By testing with a 80kg vacuum induction furnace and measuring continuous cooling transformation (CCT) curves by using Gleeble 3800 hot simulation machine the chemical composition of steel S2 (/%: 0.63~0.69C, 1.00~1.20Si, 0.40~0.60Mn, 0.20~0.40Cr, 0.40~0.50Mo, 0.15~0.25V, 0.10~0.30Ni, 0.010~0.030Nb, ≤0.015P, ≤0.010S) has been designed, and the commercial production by 120t BOF-LF-VD-300mmx390mm bloom casting-breakdown-high speed wire rolling-Stelmor control cooling process has been carried out. With the process measures including hot metal dephosphorization, sulphur content in metal ≤0.010% , control of BOF end[C] 0.10% ~0.30% , end[P] ≤0.012% , liquid end temperature 1620~1660℃, using Si-Mn pre-deoxidation in BOF tapping, LF refining slag (/%: 8~10MgO, 44~45CaO, 5~10SiO225~35Al2O3feeding calcium wire at end of LF refining, overheating extent of casting liquid ≤25℃，casting speed 0.65m/min, and controlling cooling after rolling, the cqil of alloy tool steel S2 is successfully developed. Examination results show that the each property index of Φ8mm hot-rolled coil meets the requirement of technical specification, including the austenite grain size rating 8.5~9.0, the depth of decarburization layer≤0.5%D, the HRC hardness value of hot-rolled coil 50 and the variation of HRC hardness value of same coil less than 6.2|0|0更新时间：2026-01-21
- 摘要：The steel SWRH82B is mainly applied to high strength, low relaxation pre-stressed steel wire and strand for concrete structure, required better plasticity. The abnormal fracture of Φ12. 5mm coil of steel SWRH82B (/%: 0.79~0.86C, 0.15~0.35Si, 0.60~0.90Mn, ≤0.030P, ≤0.030S, 0.17~0.50Cr) produced at Xingtai steel occurs in cold-drawn process. By metallographic analysis on abnormal fracture of coil it is found that there is obvious network of cementite in center of coil, and the center carbon segregation index of corresponding casting bloom is 1.16. With optimizing 280mmx325mm bloom casting process including increasing casting speed from original 0.5m/min to 0.7m/min and adding soft reduction process ( No1~No5 roll, 2mm, 3.5mm, 3.5 mm, 4mm and 2mm) , the center carbon segregation index of casting bloom decreases from 1.16 to 1.08, the V-shaped segregation improves obviously, the reduction of area of steel coil increases from original 35% to 39% , and nonqualified rate of steel decreases markedly.关键词：预应力钢SWRH82B;280mmx325mm铸坯;网状碳化物;中心偏析;轻压下;拉速7|0|0更新时间：2026-01-21
- 摘要：The process flowsheet of gear steel 20CrMnTiH (/%: 0.17~0.23C, 0.80~1.20Mn, 0.17~0.37Si, 1.00~1.45Cr, 0.04~0.10Ti, ≤0.035S, ≤0.030P, ≤0,0020O) is desulphurized metal-120t BOF-LF-160mmx160mm billet casting- rolling to Φ20~45mm products. With process measures including aim controlling LF refining slag basicity 4.0~8.0, ( FeO) in slag ≤0.75% , [ Als] 0.020%~0.035% , LF white slag time ≥30min, calcium treatment and argon stirring, the 145 heats analysis results show that T[O] in steel is 0.0006%~0.0018% , and the 158 heats statistic results obtains that as Ca/Als =0.10~0.14, the rating of A, B and C thin series inclusions in steel is ≤2 and that of rating of heavy series is ≤1.5 , and the rating of Ds series inclusion in steel is ≤1.0, the metallurgical quality of gear steel 20CrMnTiH improves markedly.关键词：20CrMnTiH齿轮钢;120t BOF-LF 160mmx160mm坯CC流程;LF精炼渣碱度;钢中氧含量;夹杂物;应力裂纹2|0|0更新时间：2026-01-21
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An Analysis on Surface Cracks of Φ120mm Rolled Products of Steel 25MnCrNiMoA and Process Improvement
摘要：The production flowsheet of steel 25MnCrNiMoA (/%: 0.25~0.26C, 0.22~0.25Si, 1.25~1.30Mn, 0.008~0.011P, 0.002~0.004S, 0.45~0.50Cr, 0.36~0. 38Ni, 0.24~0.26Mo, 0.04~0.08Cu, 0.025~0.031Alt) is 100t UHP EAF-LF-VD-Φ650mm bloom casting-rolling to Φ120mm products. By observing and analysis on structure at crack area, it is found that there is obvious decarburization and inclusions in structure near the cracks, and multi-ferrite strips exist at end of cracks, it shows that the quality defects of casting bloom are main reason to form surface cracks of round bar of steel 25MnCrNiMoA. With the process measures including controlling [S]≤0.003% , liquid surface fluctuation ≤2mm during casting, casting speed 0.26m/min, overheating extent of liquid 20~30°C，decreasing secondary water rate, straightening temperature of bloom ≥950°C and optimizing ingredient of shielding slag, the surface cracks of hot-rolled products of steel 25MnCrNiMoA are avoided.关键词：25MnCrNiMoA钢;Φ120mm轧材;表面裂纹;脱碳;夹杂物2|0|0更新时间：2026-01-21 - 摘要：The production flowsheet of steel FAS2225 (/%: 0.26C, 0.35Si, 1.99Mn, 0.013P, 0.046S, 0.54Cr, 0.12V, 0.02Mo, 0.08Ni, 0.0012O, 0.0070N) is pretreated hot-metal-60t top and bottom combined brown converter- LF-VD-300mmx360mm bloom casting-continuous rolling. The hole formed by center crack of 215mmx213mm rolled billet occurs. And it is obtained by analysis that the thermal stress and structure stress produced by larger heating speed and temperature gradient of casting bloom lead to cracks of bloom and forming hole-cracks of billet during rolling process. By decreasing the heating temperature of bloom at preheating zone in heating furnace from 900℃ to 750℃, prolonging heating time and decreasing temperature gradient from △200℃ to △100℃, it is available to inhibit the formation of hole-defects.关键词：贝氏体型非调质钢FAS2225;铸坯;加热;中心开裂;热应力;组织应力;预热温度4|1|0更新时间：2026-01-21
- 摘要：The production process flowsheet of Φ180mm bars of steel 2Cr12NiMo1W1V is 80t BOF-VD-LF-ESR 6t ingot-forging-900°C annealing. The central dark zone defect which un-corresponding to GB/T1979-2001 "Standard diagram for Macrostructure and Defect of Structural Steels" occurs in macrostructure of stainless steel 2Cr12NiMo1W1V finished products. By analysis it is obtained that the normal structure of the annealed steel is ferrite matrix+carbide, while the structure in central zone is lath martensite+troostite, the corrosion resistance of troostite is poor to form dark etched zone. The original annealing process is optimized to 900℃-700°C isothermal annealing process it shall be to ensure homotransformation of structure in whole section of bar, this process can eliminate and avoid the formation of bar central dark zone of steel 2Cr12NiMo1W1V.关键词：2Cr12NiMo1W1V不锈钢;棒材;低倍组织;托氏体;退火工艺4|0|0更新时间：2026-01-21
- 摘要：The tested alloy NS3105 (/%：0.021C, 0.06Si, 0.02Mn, 0.0007S, 0.007P, 29. 75Cr, 59. 90Ni, 9. 88Fe, 0.0100N) is melted by 12t vacuum induction furnace and electro-slag remelting to 3t ingot with shielding atmosphere ,forged breaking-down to Φ236 mm bloom, hot extrusion to Φ95mmx16mm pierced shell, then cold-rolled to Φ63mmx10mm tube. Effect of the solid-solution treatment of cold-rolled tube at 800〜1140°C for 5~15min on structure of steel has been studied. Results show that as the alloy NS3150 hot-worked tube cold-rolled with 60% deformation, the original equiaxed crystal structure of alloy occur large deformation, the deformed grains in cold-rolled tube start to recover-recrystallize at 800°C and the recrystallization is completed basically at 950°C；with increasing temperature and heating time the recrystallized grains of cold-rolled tube grow continuously, and the grains grow inhomogeneously at 950〜1080°C and the mix-grain and coarse-fine grain structure occur; at 1080~1120°C the grains grow homogeneously; and at more than 1120°C the grains of cold-rolled tube grow obviously and the structure is coarser. The optimum solid-solution treated temperature for cold-rolled tube of alloy NS3105 is 1080~1120°C.关键词：NS3105合金;冷轧管;固溶处理;晶粒长大2|0|0更新时间：2026-01-21
- 摘要：The production process flowsheet of tested steel NM360 (/%: 0.17C, 0.38Si, 1.28Mn, 0.014P, 0.005S, 0.23Cr, 0.14Mo, 0.02Ti, 0.04Al) 30mm plate is 90t EAF-LF-VD-180mmx1330mm slab casting-rolling to 30mm plate-quenching at 950°C and tempering at 350°C.With using the Gleeble-3500 thermal simulation testing machine, the deformation behavior of wear resistant steel NM360 at 900~1200°Cwith strain rate 0.1, 1 and 10s-1has been studied to define the thermal deformation equation and the hot working map of steel is established. Results show that the flow behavior of steel NM360 at thermal compressing deformation could be well described by the Zener-Hollomon parameter and the calculated dynamic activation energy is 305kJ/mol. With increasing temperature and decreasing strain rate, the efficiency of energy dissipation gradually increases；as at 1100°C with strain rate 0.1s-1the efficiency of deformation energy dissipation is up to max value 0.34, The wear steel has better deformability at 1070~1170°C with strain rate 0.1~0.5s-1. The production results show that with optimization process-180mm casting slab heating at (1200±20)°C , beginning rolling at (1050土10)°C , finishing rolling at (950±10)°C to 30mm plate, water cooling, tempering at 350~550°C for 1h, the NM360 steel HB hardness value is 368~385, yield strength is 830~920MPa, tensile strength is 1030~1120MPa and elongation is 10%~15% , it has better mechanical properties.关键词：NM360耐磨钢;热压缩;激活能;热加工图2|0|0更新时间：2026-01-21
- 摘要：The simulated CSP process of tested plate of Hi-B steel bearing copper (/%: 0.06C, 3.38Si, 0.14Mn, 0.013P, 0.003S, 0.019Als, 0.37Cu, 0.0015O, 0.0087N) is melting by vacuum induction furnace and mold casting to 210mmx120mmx60mm plate, rolling at 1065℃ from 60mm to 3.5mm plate with finishing rolling at 865°C by Φ350mm two-high hot rolling mill and 5 passes. The effect of both processes-water cooling after rolling and water cooling to 580℃,air cooling after rolling on structure and texture of tested steel has been studied. Results show that the cooling process of water cooling to 580°C , air cooling to room temperature after hot-rolling is available to get Goss texture with higher orientation accuracy and lower content of Brass texture, and other reasonable texture component, as compared with water cooling process after rolling it is more suitable for tested steel.关键词：含铜Hi-B钢;热轧;冷却工艺;组织;织构2|0|0更新时间：2026-01-21
- 摘要：The effect of solid solution treatment at 830~910°C and aging at 480~540°C on structure and hardness of Φ20mm plastic die steel NAK80 (/%: 0.15C, 0.30Si, 1.50Mn, 3.00Ni, 1.00Cu, 1.00Al, 0.30Mo, 0.30Cr) is tested and its aging kinetics behavior has been studied. Results show that after solid solution at 890℃，the structure of steel NAK80 is lath martensite and granular bainite, the HRC hardness value is up to 42.4, and with aging at 500℃ for 4h, the structure of steel is tempered troostite and precipitated phase, its HRC hardness value is up to 45.5. With calculating by using JMA equation it is obtained that the Avrami indexes n of steel aged at 480°C and 500°C are respectively 2.20 and 1.63 , and the apparent activation energy is 96.787J/mol.关键词：NAK80塑料模具钢;板条马氏体;粒状贝氏体;热处理;时效动力学2|0|0更新时间：2026-01-21
- 摘要：The tested low carbon bainite steel (/%: 0.08C, 0.11~0.13Si, 1.10~1.12Mn, 0.008〜0.009P, 0.002S, 0.21~0.23Ni, 0.020~0.021Ti, 0.003〜0.004Nb, 0~0.0010B, 0.0007~0.0008O, 0.0031~0.0033N) is melted by a 50kg vacuum induction furnace, rolled to 45mm plate, quenched at 930℃ and tempered at 610°C. The effect of 0.0010% boron on structure and mechanical properties of 45mm plate of 780MPa low carbon bainite steel has been studied. Results show that boron can remarkably improve the hardenability of tested steel, the structure of quenched tested steel without bearing boron is granular bainite, and the structure of quenched 0.0010% boron tested steel is lath bainite. The boron can obviously improve the mechanical properties of tested low carbon bainite steel, the tensile strength 834MPa and yield strength 771MPa of quenched-tempered bearing 0.0010% boron tested steel is higher than the tensile strength 702MPa and yield strength 591MPa of quenched-tempered without bearing boron tested steel. Adding suitable boron in steel in practical production the low carbon bainite steel can get lath bainite structure.关键词：硼;低碳贝氏体钢;组织;力学性能5|0|0更新时间：2026-01-21
- 摘要：The metallurgical flowsheet of tested steel 1Cr12Ni3Mo2VN (/%: 0.13C, 0.16Si, 0.70Mn, 11.42Cr, 2.78Ni, 1.67Mo, 0.30V, 0.0360N) is 30t EAF-LF-VD-3t ESR-forged to Φ350mm products. The effect of quenching at 950~1100°C and tempering at 200 ~700℃ on structure and properties of steel 1Cr12Ni3Mo2VN and the tensile properties of steel aging at 500°C for 500~10000h have been studied. Results show that the effect of quenching temperature at 950~1100°C on mechanical properties of steel 1Cr12Ni3Mo2VN is not obvious；the temper brittleness zone of steel is at about 600°C , nevertheless tempered at this temperature the decrease of plasticity of steel is smaller；as compared with the mechanical properties of steel 1Cr12Ni3Mo2VN quenched at 1040°C. and tempered at 540°C , with ageing at 500°C for 500h the tensile strength and yield strength of steel decrease respectively by 7.7% and 5.8% , and with ageing at 500°C for 10000h the tensile strength and yield strength of steel decrease respectively by 13.4% and 14.6% , and the reduction of area of steel decreases by 40% , its main cause is aggregation of impurity elements and deposition of carbide at grain boundary.关键词：1Cr12Ni3Mo2VN;马氏体耐热钢;热处理;组织;性能;时效2|0|0更新时间：2026-01-21
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