锻造钩尾框用25MnCrNiMoA圆钢的开发

Development of 25MnCrNiMoA Round Steel for Forging Hook Tail Frame

针对钩尾框恶劣的使用条件,对其用钢25MnCrNiMoA的开发制定了严格的技术要求。通过控制钢的化学成分,采用合理的冶炼(电炉→LF→VD)、连铸、轧制工艺,获得了纯净的钢质和良好的组织,检验表明,圆钢屈服强度≥750 MPa,抗拉强度≥890 MPa,脆性转变温度为-50℃,目前已形成小批量生产,产品质量稳定可靠,各项性能指标满足技术协议及客户使用要求。

According to the bad using condition of hook tail frame, the strict technical requirements of developing 25MnCrNiMoA steel for hook tail frame was made. By controlling the chemical composition and adopting reasonable processes （EAF→LF→VD→CC→CR）, developed 25MnCrNiMoA steel have high cleanliness and good microstructure. The test showed that the yield strength （Rp0.2）≥750 MPa, the Rm≥890 MPa and the ductile brittle transition temperature（DBTT） is-50℃. At present, the 25MnCrNiMoA steel has formed a small batch production, the product quality is stable and reliable, and each performance index meets the technical agreement and customer requirements.