摘要
采用Thermo-Calc软件进行成分设计,结合CCT曲线制定控温-控轧-控冷工艺,通过对炼钢、轧钢关键工序进行控制并联同下游用户,成功开发出长杆螺栓用非调质钢。热轧盘条A类细系夹杂物≤1.0级,B类细系夹杂物≤0.5级,D类细系夹杂物≤1.0级,组织为铁素体+珠光体,抗拉强度≥660 MPa,延伸率>18%,面缩率≥50%,总脱碳≤0.07 mm,晶粒度≥10级,冷顶锻满足1/3不开裂。盘条经拉拔、冷镦、搓丝制成的螺栓长度为830-920 mm,螺栓各项性能达到8.8级要求,且500万次疲劳极限σ_(A50)为86-101 MPa,满足主机厂(≥80 MPa)要求,该产品最终通过主机厂认证。
In this paper,the Thermo-Calc software is used for composition design,and the process of temperature control-rolling control-cooling control is formulated in combination with the CCT curve measured by thermal simulation.Through the control of the key processes of steel-making and steel rolling in parallel with downstream users,the non-quenched and tempered steel for long rod bolts is successfully developed.Type A thin inclusion level of hot rolled wire rod is≤1.0,type B thin inclusion level≤0.5 and type D thin inclusion levels ≤1.0.The microstructure is ferrite+pearlite,with the tensile strength≥660mpa,elongation>18%,surface shrinkage≥50%,total decarburization≤0.07mm,grain size≥10,and cold heading meets 1/3 without cracking.The length of bolts made of wire rod by drawing,cold heading and threading is 830-920mm.The properties of the bolts meet all the requirements of grade 8.8,and the fatigue limit σ_(A50) of 5 million times is 86-101 MPa,meeting the requirements of the automotive OEMs(≥80 MPa).The product finally passed the certification of the automotive OEMs.
作者
王杨
刘磊
周蕾
WANG Yang;LIU Lei;ZHOU Lei(Nanjing Iron&Steel Co.,Ltd.,R&D Division)
出处
《南钢科技与管理》
2022年第1期39-42,共4页
NISCO Technology and Management
关键词
新能源汽车
长杆螺栓
非调质钢
钢种开发
New Energy Vehicle
Long Rod Bolt
Non-quenched and Tempered Steel
Steel Development
