最新刊期
卷 41 ， 期 6 ， 2020
- 摘要：The research progress and application of high strength marine engineering steel having low yield ratio at home and abroad are summarized. The factors of chemical composition, metallographic structure, grain size and orientation and defect of strengthening to affect yield ratio of steel, and the multiple general process measures reducing the yield ratio are viewed. The development status in marine engineering steel at home and abroad is introduced, the yield ratio of 690 MPa marine engineering steel in China is between 0.90 and 0. 95 and the marine engineering steel with a yield ratio lower than 0. 85 will be researched in the future. One of which it the heat treatment process is a key measure to decrease the yield ratio of marine engineering steel.关键词：低屈强比;高强度;海工钢;研究进展5|0|0更新时间：2026-01-21
- 摘要：The influence of electromagnetic stirring parameters of 160 mm x 160 mm cast billet on the stirring of molten steel and the flow field in the mould is studied by numerical simulation. The results show that with frequency 1. 0 ~ 5. 0 Hz, the magnetic induction intensity decreases with the increase of frequency and the variation is large. The electromagnetic force in molten steel is symmetrically distributed along the circumference. With current intensities (200 ~ 500 A) , the magnitude of magnetic induction increases with the increase of current intensities. The electromagnetic force fluctuates greatly in the direction of radius in the mould, and there are multiple wave peaks. The largest wave peak is 15 mm away from the copper tube of the mould, which has nothing to do with the intensity of stirring current. The electromagnetic force increases with the increase of the current. The electromagnetic stirring frequency of the billet mould shall be controlled be¬tween 3 Hz and 4. 5 Hz, and the current intensity shall be controlled between 300 A and 500 A.2|0|0更新时间：2026-01-21
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Process Practice on Descaling of 150 mm x 150 mm Cast Billet for T12 Steel High Pressure Boiler Tube
摘要：The reason of the oxide scale of T12 steel containing Cr, Ni, Mo and other alloy elements in not being easy to be removed under the existing equipment of Hangang has been analyzed. Through the experiments of heating process parameter optimization, descaling water tank nozzle optimization, the optimal process method is selected to solve the problem of unclean descaling of high-pressure boiler tube casting billet. After the test, the heating time of 150 mm x 150 mm square billet is controlled within 90 ~ 100 min, and the furnace residual oxygen is controlled within 2% , blocking the water ring nozzle of mutual interference descaling and decreasing nozzle jet angle from original 38° -40° to 33° ~35°, there is no scale residue on the surface of continuous casting billet after descaling, and there is no surface defect in the finished product.2|0|0更新时间：2026-01-21 - 摘要：The oxygen and nitrogen content of GH3128 alloy with two smelting processes of "VIM + ESR" and "NVIM + ESR" are measured by oxygen nitrogen analyzer, and the thermodynamic calculation of deoxidation and denitrifiation has been carried out. The composition, size distribution and quantity of inclusions in GH3128 alloy with two smelting processes are analyzed by ASPEX SEM . The results show that： The process of M VIM + ESR" can remove the N in the alloy more effectively, the inclusions are mainly Al-Ti-0 composite oxide inclusions, with a small number of Al2O3and TiOxoxide inclusions, the inclusions in alloy by process of "NVIM + ESR" are not only oxide inclusions, but also sulfide and nitride inclusions. And uses the vacuum smelting process can effectively reduce the number of inclusions, and refine the inclusion.2|0|0更新时间：2026-01-21
- 摘要：The production process of free-cutting stainless steel 303F (/% : W0. 15C,W1. OSi, W2. 0Mn,0. 15 ~0.35S,≤0.045P,17.00 〜19.00Cr,8.00 〜10.OONi, ≤0.6Mo) wire rod is 30 t EBT EAF-AOD-LF-150 mm x 150 mm CC-Φ9.0 mm Wire Rod High-speed Rolling. By AOD reduction slag binary basicity 1.0 ~ 1.4 ,the yield of sulfur in the iron sulfide reaches more than 70% ,and control LF refining ≤ 45 min, the [S] loss can be effectively prevented. With superheat of continuous casting value of 30 ~ 40 °C ,secondary water specific water rate 0.28 ~0.32 L/kg,and using specific protective slag to effectively avoid flocculation, and get good billet surface quality, the center porosity of continuous casting billet is less than 2.0 rating,center segregation≤2.0 rating,ingot type segregation ≤2 rating, no blowhole defects. With breakdown at 1230 〜1250 ℃, final rolling at m 1050 °C and water shut-off rolling the rolling product head cracking can be effectively avoided. The results show that the rating of sulfide inclusions with main MnS in steel 303F is 2.5 〜3.0. The tensile strength of the wire rod is 650 〜670 MPa, the grain size is 11 ~ 12 rating, the value of HBW hardness is 180 〜195, and the turning chips are silver gray broken chips.4|1|0更新时间：2026-01-21
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Development and Production of 16MnCr5 Cold Heading Steel Wire Rod for Automobile Engine Valve Tappet
摘要：The production flow sheet of 16MnCr5 cold heading steel for automobile engine valve tappet is 80 t top and bottom combined blown converter→LF + RH refining→325 mm x 280 mm bloom continuous casting→high-speed wire rolling. 16MnCr5 steel is successfully developed by using basicity 4. 8 refining slag (/% ：54. 5CaO,28. 5A12O311. 2SiO26. 2MgO,0.6FeO + MnO) ,to cancel calcium treatment process,cast billet surface quenching technology,finishing rolling at 880 ~900℃; and coiling temperature at 850 ~ 870 °C. The inspection results show that the metallographic structure of Φ30 mm wire rod is uniform ferrite + pearlite with grain size rating 8 ,the reduction of area is 71. 1 % ~ 72. 5% ,1/3 cold upsetting is qualified. The oxygen content is 0.0010% ~0.0012% ,and the N content is 0.004 5% ~0. 004 7% ,the size of inclusions is all within 10μmand there is no Ds type inclusions. The inclusions are mainly single magnesium-aluminum spinel inclusions. The wire rod has good plastic deformation capacity and high purity, to meet the customer,s requirements.5|0|0更新时间：2026-01-21 - 摘要：The effect of normalizing + tempering and isothermal heat treatment processes on the microstructure and mechanical properties of U20Mn2SiCrNiMo bainite steel rail has been studied. The results show that as the test steel is normalized at 900 °C + tempered at 300 °C ,the mechanical properties are tensile strength 1396 MPa,elongation 16.0% impact absorption work KU257 J,and HB hardness value 402；as the test steel is heated at 870 ~ 930 °C after air-cooied to 300 °C isothermal treatment,the mechanical properties are tensile strength 300 MPa,elongation 17.0% ,impact absorption work KU2≥80 J,HB hardness value 375 ~ 395 ；By comparison with the traditional normalizing + tempering process, the optimized isothermal heat treatment process can greatly improve the impact toughness of U20Mn2SiCrNiMo bainite steel rails i. e. the room temperature impact absorption work has been increased from 57 J to more than 80 J ,by 40% ~ 56% , while the elongation after breaking remains basically unchanged, tensile strength and tread hardness slightly lower. The best optimized process is normalizing at 870 °C. , air-cooling to 300°C for 4 hours air-cooling.2|0|0更新时间：2026-01-21
- 摘要：According to issue of increasing cost and decreasing liquid quality by BOF recarburization process to melt medium and high carbon steel using semi-steel at Pan Gang, the chemical thermal compensating process by increasing silicon content of semi-steel is adopted, and based on dephosphorization thermodynamics in BOF and enrichment regularity of phosphor in slag, it is obtaind that enrichment phase of phosphor in slag is 2CaO • SiO2. By using technologic measures such as fast slagging, reduce tapping temperature, it is obtained that the enrichment phase of phosphor in slag is increased, which improve the dephosphorization effect. Results of test indicate that the new thermal compensating process improves the thermal resource of semi-steel as well as shorten the slag forming time from 4. 1 min to 2. 5 min,and the average carbon content of steel at endpoint is of BOF 0.18% , it is obtaind that temperature is 1653 °C ,TFe content of slag is average reduced by 2. 81 percent point,phosphor content of steel is all less than 0.015% .关键词：120 t转炉半钢冶炼;热补偿;脱磷;终点碳2|0|0更新时间：2026-01-21
- 摘要：By analyzing on ingredient of nozzle clogging and mechanism of clogging-forming it is obtained, that the nozzle clogging in casting process of Ti-bearing Al-killed ultra-low carbon steel has a hierarchical structure, consisting of a reaction layer and a bonding layer; inside, the reaction layer is caused by the reaction of the acid material in refractory with Al in the steel and the precipitation of inclusions caused by the temperature of molten steel decreasing due to contact with the wall surface of the clogging, while the bonding layer is caused by the accumulation of inclusions accompanied by cold steel； the mass percentage of Al in the bonding layer increases from the inner to the outer layer, and the mass percentage of Ti decreases. By taking such measures as (FeO + MnO) is controlled below 8% by modifying top slags, the mass percent [0] after RH decarburization is controlled within 0. 030% , the tundish argon replacement process before casting is implemented and so on, the number of continuous casting heats of Ti-bearing Al-killed ultra-low carbon steel increases from original 3 to 5, and the nozzle clogging rate has been reduced from original 80% to 30%.关键词：铝镇静钢;含Ti;水口堵塞;超低碳钢2|0|0更新时间：2026-01-21
- 摘要：In view of the high silicon and phosphorus content of hot metal in a steel works, a converter slag-retaining double-slag smelting process is used to obtain a stable dephosphorization rate of hot metal. The specific process is to add slag-forming materials such as lime and sludge balls after the start of the blowing process for 3 min. The oxygen supply intensity is 2. 5 m3(t ·min) at 0 ~ 3 min, and 3. 2 m3/( t ·min) at 3 ~ 4. 5 min. The temperature is controlled at about 1320 °C. After the converter has first deslagging, it starts to blow and adds the late slag forming material. When the carbon monoxide in the furnace rises to a stable level, the oxygen lance position is raised appropriately to improve slagging and control the end-point carbon. The test results show that the average dephosphorization rate of hot metal in the dephosphorization period is 58.09% ,and the average dephosphorization rate of molten steel in the decarburization period is 85. 56% ； When the temperature of the semi-steel is 1320 °C ,the basicity of the slag is 2.0,and the TFe content in the slag is 18% ,a better dephosphorization effect can be obtained in the dephosphorization period. When the molten steel temperature of the converter liquid after first deslagging is 1580 °C ,the basicity of the final slag is 3. 5,and the TFe content in the final slag is 20%, a better dephosphorization effect can be obtained in the decarburization period. [P]e/[P]rratio at the end of the converter is 0. 90. The petrographic composition of the slag during dephosphorization and decarburization poriod from the experiment is suitable for dephosphorization of hot metal.2|0|0更新时间：2026-01-21
- 摘要：By converter + LF dephosphorization process for 12Cr2MolR steel for hydrogen atmosphere the BOF end [P] can be controlled <0.010% and end [O] >0.06% , the average dephosphorization rate of steel in LF is 73% and average rephosphoration rate of steel after slagging is 28% , the tundish [P] can be stably controlled below 0.005%. The average phosphorus content is reduced by 0. 001% compared with the initial retained slag + double slag method , the production cost is reduced by about ¥ 30 /t steel. Phosphorus control is no longer a restricted link in production and upgrading of low phosphorus steel grade.2|0|0更新时间：2026-01-21
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Process Practice of 300 t BOF Smelting with Low Lance Position and Low End-Point Oxygen for IF Steel
摘要：On the basis of theoretical analysis of dephosphorization, by using low lance position smelting and low end¬point oxygen tapping, increasing diameter of tapping hole and reducing the end-point temperature, and optimizing bottom blowing process to reduce the carbon-oxygen equilibrium, a better dephosphorization effect is achieved. The results of production and application show that after adopting large tapping hole and optimizing bottom blowing process, the tapping time of 300 t converter is shortened to 5. 1 min, shortened by 1. 9 min； the end-point temperature of IF steel is reduced to 1670.6 T , reduced by 17.4 °C ；the carbon-oxygen product is reduced to 13.3 , reduced by 8.9; the end-point oxygen is reduced to 422.5 x 10. Under the condition of increase of hot metal phosphorus by 0.010% ,decrease of lance position by 30 cm and decrease of end-point oxygen by 153.3 x 10-6the average end-point phosphorus content after process optimization is reduced to 0.012 4% , which can meet the requirements of dephosphorization effect of IF steel smelting in converter.2|0|0更新时间：2026-01-21 - 摘要：Based on the reasonable design of chemical composition HRB400E steel (/% ：0. 21 ~0. 25C,0. 40 〜 0. 65Si, 1.40 ~ 1. 55Mn, W0. 040P, W0. 0405,0. 015 ~ 0. 025Nb,6. 005 〜0. 008N), the effects of different heating temperature and controlled rolling and controlled cooling temperature on the mechanical properties, metallographic structure and aging corrosion of steel bar surface are studied. The optimum rolling temperature parameters are： the heating temperature 1 140 ~ 1 170 T , the starting rolling temperature 1040 ~ 1060 °C , the finishing rolling temperature 1000 〜 1030 °C , and the cold bed temperature 870 ~890 V. after the final rolling. Results show that the yield strength of niobium microalloyed HRB400E steel is 450 ~475 MPa, the precipitates in steel are mainly Nb( C,N) with a particle size of 300 ~ 600 nm, which are distributed on the network carbide, the edge of the network carbide and the inside of the grain near the grain boundary.2|1|0更新时间：2026-01-21
- 摘要：The flowsheet of steel 27 CrMoNbV at Pansteel is hot metal pretreatment-120 t top bottom combined blown BOF-LF-RH-360 mm x450 mm bloom CC process. With the process optimization including hot metal deep desulfurization pretreatment, BOF double slag dephosphorization process, deep desulfurization in the process of BOF tapping and LF refining with (1. 6 ~2. 2) CaO/Al2O3refining slag system, RH refining treatment by feeding Ca-Si wire and protective casting, the chemical composition stability of steel 27CrMoNbV is produced with P ≤ 0.010% , S≤0.004% , [ H] ≤ 1. 5 x 10-6T[O]≤0.0011%. The rating of non-metallic inclusion of A, B, C, D and Ds are all≤ 1.0 rating, which fully meet technical requirements.2|0|0更新时间：2026-01-21
- 摘要：By the method of using a full-process system sampling, a systematic analysis and research on the evolution of the oxygen content and the inclusion characteristics in a 20CrMnTi gear steel produced in the process of 120 t BOF-LF- VD-CC have been carried out. The experimental results show that using the technology of aluminum deoxidation and the high-basicity [ (CaO)/(SiO2) =3. 8 ~7 ] reduction slag, the T[O] in the slab can be less than 20 x 10-6the average T[O] of liquid in tundish gas increases by 6 x 10-6during the steelmaking process of gear steel, the inclusions in steel have completed the transformation from Al2O3→ Al2O3-MgO—;Al2O3-CaO-MgO.4|0|0更新时间：2026-01-21
- 摘要：The microstructure and properties of the heat affected coarse grain zone of steel 07MnCrMoVR with post¬weld heat treated at 460 ~ 660 °C for 2 h are analyzed by means of optical microscope, scanning microscope, transmission electron microscope and impact toughness tester. The results show that with increase of post-weld heat treatment temperature, the - 20 °C impact toughness of post-weld heat affected coarse-grained zone decreases firstly and then increases. The steel with post-weld heat treatment between 580 °C. to 620 ℃ can occur reheat cracks tend, the impact specimen is brittle fracture ,cleavage fracture and microcracks along grain boundary ,the main reason is that the carbide precipitates along the grain boundary and grows up to weaken binding energy of the grain boundary, which leads to the decrease of the impact toughness at low temperature. With post-weld heat treated ≥620°C , recrystallization occurs in 07MnCrMoVR steel, dislocation disappears ,and the low temperature impact toughness of the steel increases again due to the combined growth of ferrite grains. The optimum post-weld heat treatment of steel is 460 ~ 500°C X 2 h.2|0|0更新时间：2026-01-21
- 摘要：In this paper, the influence of high temperature diffusion heat treatment on Laves phase and elements segregation in 50 kg vacuum induction melted Ni-24Fe-14Cr-8Mo nickel base alloy is studied. The alloy is heat-treated at different temperatures for different times, and the microstructure and element distribution are investigated through Optical Microscope (OM), Scanning Electron Microscope (SEM) , Electron Probe Micro-Analyzer (EPMA) and Metallographic Processing (MP). Results indicate that island-shaped Laves phase obviously precipitates in the interdendritic area led to a serious elements segregation. The incipient temperature of Laves phase is at 1180 ~ 1200 ℃. When the alloy is soaked at 1180 ℃ for 7 ~ 100 h, the volume fraction of Laves phase kept decreases with diffusion treatment time in an exponential pattern with Vf= 11.557 8exp( -0.1432 t) ； Laves phase could not be totally dissolved in less than 40 h but almost disappeared after 76 h at 1180℃；elements segregation could be further improved after 100 h high temperature diffusion heat treated at 1180℃.It could be concluded that for Ni-24Fe-14Cr-8Mo alloy the high diffusion heat treatment temperature should not be higher than incipient temperature Laves phase, and a treatment at 1 180 °C for 100 h could effectively reduce Laves phase fraction and elements segregation.2|0|0更新时间：2026-01-21
- 摘要：The process and properties of 700MPa grade hot rolled dual phase steel DP700 (/% : C 0.08 ~ 0.12 ,Si 0.08 ~0.12,Mn 1.30 ~ 1.150,P≤ 0.015,S ≤0,005 ,Cr 0.50 ~0.70,Ca ≥0.0015, Al≥0.015) development at Baosteel Meishan 1780 hot rolling mill are summarized. The developed plate has superior surface quality, its properties are Yield strength≥400 MPa,Tensile strength≥700 MPa,Elongation after fracture N≥ 17% (b = 20 mm, L0= 80 mm) , Hole expansion rate ≥35% ,50% survival rate fatigue limit 475 MPa. Results show that the steel DP700 is one of new material for Auto industry with good application prospect.2|0|0更新时间：2026-01-21
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