关键词: 42CrMoA钢, 带状组织, 枝晶偏析, 改善措施

Abstract: The band structure in 42CrMoA hot rolled steel is observed and analyzed by scanning electron microscope (SEM) and energy dispersive spectrum (EDS). The results show that there is a serious band structure in the hot rolled structure of 42CrMoA steel and a second type of band structure such as bainite except ferrite, and the band structure is 3 rating. EDS line scan shows that segregated C and Cr elements seriously among dendrites, which is the main reason for the formation of banded structure. By controlling measure of the superheat of the molten steel in the continuous casting tundish 20 ~30℃. ,the casting speed of 0.75 m/min,the electromagnetic stirring parameter 400 A 8 Hz,and the specific water volume of the secondary cooling decreasing from 0.30 L/kg to 0.25 L/kg and end rolling temperature decreasing from 950 ℃ to 910 ℃ ,the steel banded structure decreases from 3 rating to ≤2 rating.