包钢钢联股份有限公司炼钢厂采用120 t顶底复吹转炉-100 t LF(VD)-5流Φ300 mm铸坯连铸工艺流程试生产X65管线钢13MnNbTi(%:0.10～0.16C、1.20～1.40Mn、0.03～0.05Nb、0.01～0.02Ti、0.025～0.05Al)。生产实践表明,通过铁水脱硫([S]≤0...包钢钢联股份有限公司炼钢厂采用120 t顶底复吹转炉-100 t LF(VD)-5流Φ300 mm铸坯连铸工艺流程试生产X65管线钢13MnNbTi(%:0.10～0.16C、1.20～1.40Mn、0.03～0.05Nb、0.01～0.02Ti、0.025～0.05Al)。生产实践表明,通过铁水脱硫([S]≤0.005%),转炉挡渣出钢,精炼渣碱度≥3.0,VD处理≥13 min,可以使[S]≤0.005%、[P]≤0.015%、[H]≤1.5×10^(-6)。通过全程保护浇铸和结晶器电磁搅拌工艺,钢中氧含量(13～21)×10^(-6),平均氧含量16.44×10^(-6),铸坯表面质量良好,低倍组织0～1级。展开更多
EA4T车轴钢(/%:0.22～0.29C、0.15～0.40Si、0.50～0.80Mn、≤0.020P、≤0.015S、0.90～1.20Cr、0.15～0.30Mo、≤0.06V)采用30 t EBT电弧炉40 t LF/VD-5 t铸锭工艺生产,并经8 MN油压机锻成300 mm x300mm钢坯,锻造比≥9。结果表明,EA4T...EA4T车轴钢(/%:0.22～0.29C、0.15～0.40Si、0.50～0.80Mn、≤0.020P、≤0.015S、0.90～1.20Cr、0.15～0.30Mo、≤0.06V)采用30 t EBT电弧炉40 t LF/VD-5 t铸锭工艺生产,并经8 MN油压机锻成300 mm x300mm钢坯,锻造比≥9。结果表明,EA4T钢[O]为(12-15)×10^(-6),[H]为(1.2～1.6)×10^(-6),经900～920℃淬火,600～650℃回火后,抗拉强度R_m721~745 N/mm^2,屈服强度R_eh463～470 N/mm^2,伸长率A_5 19.0%～19.5%,纵向冲击功53～73 J,横向冲击功36～41 J,组织为贝氏体一回火马氏体,10~7循环疲劳极限为350 N/mm^2。展开更多
简述了莱钢50 t EAF-LF(VD)-CC流程中合金钢260 mm×300 mm连铸坯质量控制集成技术的开发和应用效果。通过合理的铸坯纯净度和全程保护浇铸,二冷动态控制的二冷工艺设备设计,工艺设备精度参数群优化,热装工艺的铸坯质量在线预报判...简述了莱钢50 t EAF-LF(VD)-CC流程中合金钢260 mm×300 mm连铸坯质量控制集成技术的开发和应用效果。通过合理的铸坯纯净度和全程保护浇铸,二冷动态控制的二冷工艺设备设计,工艺设备精度参数群优化,热装工艺的铸坯质量在线预报判定系统等控制技术的开发,提高了铸坯质量,钢材酸浸低倍检验合格率由2007年的97.50%提高到2009年的99.01%,铸坯合格率在99.92%以上,成材率由原来的96.50%提高到96.80%,铸坯热装率由45%提高到75%。展开更多
The thermal elastic stresses induced in 300 mm Si crystal may be great troubles because it can incur the generation of dislocations and undesirable excessive residual stresses. A special thermal modeling tool, CrysVUn...The thermal elastic stresses induced in 300 mm Si crystal may be great troubles because it can incur the generation of dislocations and undesirable excessive residual stresses. A special thermal modeling tool, CrysVUn, was used for numerical analysis of thermal elastic stresses and stress distribution of 300 mm Si crystal under the consideration of different thermal shields and gas flow conditions. The adopted governing partial equations for stress calculation are Cauchy′s first and second laws of motion. It is demonstrated that the presence and shape of thermal shield, the gas pressure and velocity can strongly affect von Mises stress distribution in Si crystal. With steep-wall shield, however, the maximal stress and ratio of high stress area are relatively low. With slope-wall shield or without shield, both maximal stress and ratio of high stress area are increased in evidence. Whether thermal shields are used or not, the increase of gas flow velocity could raise the stress level. In contrast, the increase of gas pressure cannot result in so significant effect. The influence of thermal shield and gas flow should be attributed to the modification of heat conduction and heat radiation by them.展开更多
文摘EA4T车轴钢(/%:0.22～0.29C、0.15～0.40Si、0.50～0.80Mn、≤0.020P、≤0.015S、0.90～1.20Cr、0.15～0.30Mo、≤0.06V)采用30 t EBT电弧炉40 t LF/VD-5 t铸锭工艺生产,并经8 MN油压机锻成300 mm x300mm钢坯,锻造比≥9。结果表明,EA4T钢[O]为(12-15)×10^(-6),[H]为(1.2～1.6)×10^(-6),经900～920℃淬火,600～650℃回火后,抗拉强度R_m721~745 N/mm^2,屈服强度R_eh463～470 N/mm^2,伸长率A_5 19.0%～19.5%,纵向冲击功53～73 J,横向冲击功36～41 J,组织为贝氏体一回火马氏体,10~7循环疲劳极限为350 N/mm^2。
文摘简述了莱钢50 t EAF-LF(VD)-CC流程中合金钢260 mm×300 mm连铸坯质量控制集成技术的开发和应用效果。通过合理的铸坯纯净度和全程保护浇铸,二冷动态控制的二冷工艺设备设计,工艺设备精度参数群优化,热装工艺的铸坯质量在线预报判定系统等控制技术的开发,提高了铸坯质量,钢材酸浸低倍检验合格率由2007年的97.50%提高到2009年的99.01%,铸坯合格率在99.92%以上,成材率由原来的96.50%提高到96.80%,铸坯热装率由45%提高到75%。
基金The project was finanicallysupported bythe International Scientific and Technical Cooperation Major Planning Project(2005DFA5105).
文摘The thermal elastic stresses induced in 300 mm Si crystal may be great troubles because it can incur the generation of dislocations and undesirable excessive residual stresses. A special thermal modeling tool, CrysVUn, was used for numerical analysis of thermal elastic stresses and stress distribution of 300 mm Si crystal under the consideration of different thermal shields and gas flow conditions. The adopted governing partial equations for stress calculation are Cauchy′s first and second laws of motion. It is demonstrated that the presence and shape of thermal shield, the gas pressure and velocity can strongly affect von Mises stress distribution in Si crystal. With steep-wall shield, however, the maximal stress and ratio of high stress area are relatively low. With slope-wall shield or without shield, both maximal stress and ratio of high stress area are increased in evidence. Whether thermal shields are used or not, the increase of gas flow velocity could raise the stress level. In contrast, the increase of gas pressure cannot result in so significant effect. The influence of thermal shield and gas flow should be attributed to the modification of heat conduction and heat radiation by them.
