≥0.015Alt)。试验钢的工艺流程为260 t BOF-LF-RH-230 mm板坯连铸-热轧成2~6 mm板。通过Nb-Ti复合微合金化和Ca处理
控制精轧结束温度840~880℃
层流冷却速度≥60℃/s
卷取520~580℃
热轧钢卷的冷却速度≤10℃/h等工艺措施
热轧带钢具有良好的表面质量
组织为细晶铁素体+Nb-Ti碳氮化物
力学性能为上屈服强度760~790 MPa
抗拉强度860~910 MPa
伸长率21%~25%
满足用户要求。
Abstract
The yield strength 750 MPa high strength low alloy (HSLA) steel for container (/% : 0.06 ~0.09C
0.25 ~0.35Si
1.60 ~1.80Mn
≤0.015P
≤0.003S
0.10 ~0.20Mo
0.05 ~0.06Nb
0.09 ~0.llTi
≥ 0.0015Ca
≥0.015Alt) has been designed and developed. The process flowsheet for tested steel is 260 t BOF-LF-RH-230 mm slab casting-hot-rolling to 2 ~ 6 mm plate. With the process measures including Nb-Ti compound microalloying and Ca treatment
controlling finishing rolling temperature 840 -880 ℃
lamina flow cooling rate ≥ 60℃ /S
coiling at 520 -580℃
and hot-rolled coil cooling rate ≤ 10 °C/h, the hot-rolled strip coil has better surface quality
its structure is fine grain ferrite + Nb-Ti carbonitride
and the mechanical properties of strip are upper yield strength 760 〜790 MPa
tensile strength 860 -910 MPa
and elongation 21% ~25% to meet the requirement of user.