图为20mm Q690NHH TMCP态扫描组织,可以看出,由于水冷冷速较快,钢板组织为板条贝氏体+少量粒状贝氏体,返红温度400℃晶粒尺寸更小。
The picture shows the 20mm Q690NHH TMCP state scanning structure. It can be seen that due to the faster water cooling rate, the steel plate structure is lath bainite + a small amount of granular bainite, and the grain size is smaller at 400 ℃.