优质20MnSiVⅢ级热轧螺纹钢筋的开发

总结了我公司大亚湾岭澳核电站二切工程核岛和外围岛用Ⅲ级20MnSiV钢筋的成分设计、炼钢和轧钢方面的研究结果。它保证了大亚湾核电站工程用钢筋的质量。     

优质20MnSiVⅢ级热轧螺纹钢筋的开发

目前正大力推荐使用Ⅲ级钢筋,我公司又同大亚湾岭澳核电站签订了二期工程核岛和外围岛用Ⅲ级20MnSiV钢筋的供货合同。合同中对钢筋成份、性能、表面和包装质量都提出了比GB1499-91(Y)标准更严格的要求。本文总结了开发这种优质钢筋的成份设计和研究开发结果,保证了大亚湾核电站工程用钢筋的供应。     

氮化钒合金在400MPa级钢筋中的应用

介绍了攀钢采用氮化钒合金化与钒铁合金化生产400MPa级含钒钢筋(20MnSiVⅢ级钢筋)的对比试验结果,研究了钒、氮微合金化对钢筋的性能和组织的影响,探讨了氮化钒的强化机理,比较了使用两种合金的生产成本。     

新Ⅲ级带肋钢筋开发

介绍了杭钢新Ⅲ级带肋钢筋的研制过程及钢筋实物质量情况。通过精心设计钢种（20MnSiV）的化学成分，经80t电弧记冶炼－LF精炼－连铸－小连轧轧制，钢筋质量完全符合GB1499－1998的要求，满足了宁波机场建设的需要。     

转炉直接合金化冶炼20MnSiV的试验研究

20MnSiVⅢ级高强度钢筋,是我国近几年发展较快的一种新型建筑钢材。新兴铸管集团有限责任公司炼钢厂根据冶炼设备条件,进行了炉钒渣直接合金化冶炼20MnSiVⅢ级钢筋的试验研究。结果表明,转炉钒渣直接合金化冶炼20MnSiVⅢ级钢筋工艺是可行的,经济效益显著,钢的化学成分和力学性能符合国家标准,得到了2钢的力学性能和成分关系的经验公式。     

钒渣直接合金化冶炼20MnSiV生产新Ⅲ级钢筋

介绍了钒渣和还原剂的混合物-钒球在转炉上冶炼20MnSiV生产新Ⅲ级钢筋的情况。试验表明,使用钒渣和还原剂的混合物-钒球代替钒铁或五氧化二钒在包内进行合金化生产低合金钢,不但在技术上可行,在经济上也是有利的。     

VN合金化对20MnSiV钢筋钢组织的影响

对比研究了VN合金化和Fe-V合金化的20MnSiV钢筋钢的显微组织和钒析出物。结果表明：用VN合金化的20MnSiV钢筋钢的铁素体量较多,珠光体量较少;钒析出物的量明显较多。顶计用vN合金生产的20MnSiV钢筋钢将具有较高的屈服强度和较低的冲击转变温度。     

HRB400Ⅲ钢筋抗震性能研究

从强度与塑性的配合、应变时效敏感性、低温脆性、可焊性等方面对Ф20mm牌号为20MnSiV HRB400Ⅲ钢筋的抗震性能进行了系统的测试和研究。结果表明,钢筋应变时效后韧脆转变温度较高,低温抗震性能差;钢筋碳当量高,焊接性能有待改善;微观分析和成分分析结果表明,为加强钢筋的抗震性能,微合金元素应当适当调整。     

20MnSiV(N)新Ⅲ级螺纹钢筋

介绍了开发20MnS iV(N)级钢筋的前景、成分分析,并对20MnS iV(N)级钢筋V(N)的强化原理作了简要分析。     

20MnSiV Ⅲ级钢筋焊缝和热影响区拉伸脆性断裂的分析

分析了Φ32mm20MnSiVⅢ级钢筋搭接焊试样拉力试验断口—焊缝和热影响区脆性断裂。断口处HV硬度试验和扫描电镜观察表明，焊缝和热影响区存在大量魏氏组织和贝氏体,马氏体是拉伸脆性断裂的主要原因，夹杂物向晶界偏聚导致沿晶脆性断裂，小热量输入多道焊接可改善热影响区的组织和韧性。     

针状铁素体对含铌HRB400钢筋屈服行为的影响

对比研究成分为20MnSiV和16MnVNb的HRB400钢筋的屈服行为,在同一轧制工艺条件下,与含钒钢筋相比,含铌钢筋应力-应变曲线没有明显的屈服平台。对试验钢的化学成分、显微硬度进行测试分析,利用光学显微镜、扫描电镜和透射电镜对试验钢的微观组织进行观察。结果表明,20MnSiV试验钢组织主要为铁素体＋珠光体组织,16MnVNb的组织为等轴状铁素体＋珠光体＋针状铁素体,其中针状铁素体周围珠光体退化明显。针状铁素体的显微硬度介于珠光体与铁素体之间,其内部存在高密度位错。针状铁素体组织的大量存在是导致含铌HRB400钢筋无屈服平台的原因。     

高氮钒微合金化钢筋的应用研究

主要介绍在２０ＭｎＳｉＶ钢中,加入钒铁ＶＦｅ（５１．６％Ｖ）及美国钒公司的专利产品富氮钒合金ＶＮ１２（８０％Ｖ,１２％Ｎ）的对比试验,研究了钒、氮复合微合金化对钢筋的性能的影响,分析了采用钒铁及富氮钒合金微合金化时,钢筋中钒含量的节约及其技术经济性。     

Corrosion of High Chromium and Conventional Steels Embedded in Concrete

Corrosion rates of high chromium and conventional steel rebars were measured and compared by conducting two studies. One was on concrete blocks and the other was on bare steel rebars. In the former study, concrete blocks that had been made with two different steel rebars were placed in sodium chloride solutions, and air was blown through the solutions to accelerate corrosion of the embedded steel rebars. These blocks were taken out of the solution periodically, and the corrosion rates of the rebars were measured with a 3LP device. In the latter study, the bare rebars of the two steels were also corroded in sodium chloride solutions through which air was blown, withdrawn periodically, dried, and weighed after the corrosion products were removed. The corrosion rates were measured by the reduction of the weight of the rebars. In the study on concrete blocks, it was found that the corrosion rate increases for both steels as the concentration of sodium chloride in solution increases. It was also found that the corrosion rate of concrete blocks reinforced with conventional steel was about twice as much as that of the concrete blocks reinforced with high chromium steel after 132 days of exposure. From the study on bare steel rebars, it was found that the rate of corrosion of conventional steel was 12 times as much as that of high chromium steel at 0.1% sodium chloride, and the ratio decreased to 2 times as much when the sodium chloride concentration was increased to 3%. It was also found that the corrosion rate of high chromium steel was very sensitive to sodium chloride concentrations whereas that of conventional steel was not sensitive. The corrosion products were analyzed using x-ray diffraction and atomic absorption spectroscopy to identify the minerals present in them. It was found that corrosion products produced on the high chromium steel were predominantly lepidocrocite (γ-FeOOH) and hematite (Fe2O3), whereas that on the surface of conventional steel was predominantly magnetite (Fe3O4). It appears that the former iron oxides form an adherent and nonporous protective layer while the latter iron oxides (magnetite) do not, which can explain the distinct difference in corrosion rates of the two steel rebars.     

不同相区轧制对螺纹钢组织和性能影响

为了降低螺纹钢生产线坯料的生产成本,通过安装在16号轧机之后的预水冷装置对进入17号轧机的螺纹钢进行不同温度的控制,再经过17号和18号轧机对不同温度的螺纹钢进行轧制。探究了钢坯在不同相区进行轧制时对其组织性能的影响,结果表明,当钢种为HRB400-1NbS(Nb质量分数为0.025%)的螺纹钢在奥氏体未再结晶区轧制时(进入17号轧机的温度为(880±20) ℃),其屈服强度为437 MPa,抗拉强度为595 MPa;当钢种为HRB400-0NbS(Nb质量分数为0.015%)的螺纹钢在两相区轧制时(进入17号轧机的温度为(780±20) ℃),其屈服强度为435 MPa,抗拉强度为605 MPa;两者力学性能相差不大,这是因为HRB400-0NbS钢种在两相区轧制时,其晶粒度/级为10.5,相比HRB400-1NbS钢种在奥氏体未再结晶区轧制时晶粒度/级为9.5更加细小,通过细晶强化弥补了Nb所产出的第二相强化作用,为螺纹钢生产线坯料节约了每吨40~50元的成本。     

管桩钢筋用30MnSiV热轧盘条的研制

从提高国产管桩用阴螺纹钢筋性能出发，自主开发了30MnSiV钢种，研究了30MnSiV热轧盘条的生产工艺、热处理工艺与钢筋力学性能之间的关系，为现场工艺的确定提供了可靠的依据。     

VN12合金在钒氮微合金化钢中的应用研究

本文主要介绍了在济钢２０ＭｎＳｉＶ、１６ＭｎＶ钢中,加入钒铁合金ＶＦｅ（５１．６％Ｖ）及美国钒公司提供的专利产品富氮钒合金ＶＮ１２（８０％Ｖ,１２％Ｎ）的对比试验,研究了钒、氮复合微合金化对钢的力学性能的影响,分析了采用钒铁及富氮钒合金微合金化时,钢中钒含量的差别及其经济性。     

非调质钢50MnSiV新能源汽车电机轴的开发

非调质钢50MnSiV(/%:0. 50C,0.52S,1.20Mn,0.010P,0.025S,0.15Cr,0.10V,0.015Ti,0.015N)制造的新能源汽车电机轴,省去传统调质钢20CrMnTiH渗碳热处理和矫正精整工序,不仅可提高材料95%利用率和2天交货周期,还可以降低25%成本。50MnSiV钢抗拉强度1100 MPa、屈服强度858 MPa、冲击功48J。其静扭扭矩(4697 Nm)、疲劳寿命(±1600 Nm双向扭转12万次、±1400 Nm双向扭转27万次)较渗碳20CrMnTiH钢提高了27%和93%～140%,并且其性能指标和8万公里的路试结果均满足电机轴的技术要求。