图为40mm Q690NHH 不同回火温度的扫描组织,可以看出,回火后钢板组织由板条贝氏体为主的组织变成板条贝氏体+粒状贝氏体为主的组织,并且形成大量的M-A,钢板的塑韧性进一步提高,710℃回火的组织较690℃回火组织更为粗化。
The picture shows the scanning structure of 40mm Q690NHH at different tempering temperatures. It can be seen that after tempering, the structure of the steel plate is changed from lath bainite to lath bainite + granular bainite. With a large amount of MA, the ductility of the steel plate is further improved, and the structure tempered at 710°C is coarser than the structure tempered at 690°C.