普通取向硅钢板坯低温加热生产工艺及磁性研究

Investigation on Process and Magnetic Properties of Lowtemperature Heating Common Grain-oriented Silicon Steel Slab

研究了以Cu2S+AlN为抑制剂采用低温板坯加热二次冷轧法和中间厚度完全脱碳的工艺生产0.30 mm厚普通取向硅钢(/%:0.03~0.05C、3.0~3.2Si、0.18~0.24Mn、0.005~0.012S、0.006~0.011N、0.012~0.024Als、0.4~0.55Cu)的工艺过程。研究表明:加热温度在1 220~1 300℃时,酸溶铝(Als)和氮(N)(/%)分别在0.01~0.022、0.007~0.011时,随着Als和N含量的增加,磁感升高,铁损降低,成品磁性能呈现逐步优化趋势,产品合格率高;二次冷轧压下率控制在55%~60%(即一次冷轧后厚度0.65~0.70 mm)可保证得到均匀的一次晶粒和适量的高斯晶核;脱碳退火温度、时间和板厚对脱碳影响较大,退火气氛和加湿水温影响较小;回复退火对磁性能影响不大。通过研究,确定了最佳工艺参数:1 290℃加热,1 160℃开轧,终轧温度930~960℃;二次冷轧压下率在55%~60%;中间退火温度840~850℃,加湿水温65℃,退火气氛20%H2+80%N2,退火时间根据冷轧板厚度不同而变化,8~9 min;回复退火工艺可略去。

The investigation was carried out on the process of 0.30 mm grain-oriented silicon steel(/%:0.03~0.05 C、3.0~3.2 Si、0.18~0.24 Mn、0.005~0.012 S、0.006~0.011 N、0.012~0.024 Als、0.4~0.55 Cu)produced by low-temperature slab heating technology,in which the inhibitor of Cu2 S+AlN was used and the two-stage cold rolling technology with completing decarburization in the intermediate thickness of cold sheet was used too.It is proved that when the heating temperature is 1 220~1 300℃,the magnetic induction increases as well as the core loss decreases with increasing Als and N in the range of Als(/%)0.01~0.022 and N(/%)0.007~0.011,and the ratio of qualified products is higher.The second cold rolling rate within 55%~60%(i.e.the thickness after first rolling being 0.65~0.70 mm)guarantees the uniform primary grains and proper quantities of Goss crystal nucleus.Temperature,time and thickness affect on decarburation remarkably,while the effect of atmosphere and temperature of water for adding wet is light.In addition,the recovery annealing make for little contribution to improve magnetic properties.The most proper process is heating at 1 290℃,hot rolling at 1 160℃,finishing temperature at 930~960℃,second cold rolling rate within 55%~60%,intermediate decarburization temperature at 840~850℃,water temperature for adding wet at 65℃,annealing atmosphere with 20%H2+80%N2,annealing for 8~9 min utes based on thickness,and the recovery annealing process can be removed.