低碳冷轧薄板罩式退火工艺优化及性能分析

Process optimization and performance analysis of batch annealing for low carbon cold rolled sheet

冷轧带钢不同阶段退火温度的变化会直接影响带钢的回复再结晶行为,对其显微组织产生不同的影响,致使其具有不同的力学性能。为此,在全氢罩式退火炉中对DD11热轧原料经过冷轧后的带钢采用不同退火工艺处理,分析了退火工艺对冷轧带钢性能的影响。结果表明：提高再结晶退火温度和延长退火时间,材料显微组织基本由等轴晶粒组成,晶界析出条状三次渗碳体。降低回复阶段升温速度,材料能释放出更多的畸变能,可降低再结晶温度。通过优化退火工艺,普通DD11热轧原料的冷轧带钢可达到DC03性能要求。

The change of annealing temperature in different stages will directly affect the recrystallization behavior of strip,and have different effects on microstructure,which makes it have different mechanical properties.Therefore,the influence of annealing process on the low carbon cold rolled sheet properties was analyzed in a full-hydrogen batch annealing furnace.The results showed that improving the recrystallization annealing temperature and prolonging the annealing time could obtain the microstructure of isometric crystal and tertiary cementite,reducing the rate of temperature increase could release more distortion and the recrystallization temperature.Through optimizing the annealing process,the hot rolled DD11 raw materials could be cold rolled to achieve the DC03 steel performance.