Study On Cleanness And Quality Control Of 65Mn Strip Steel

65 Mn steel strength,hardness and flexibility are better than the 65 steel,is used as a small size spring,saw blade,cutter and so on.The inclusions in the 65 Mn steel has important effect on performance and life.In order to control the main inclusion species and grades affecting the performance of 65 Mn steel,based on the continuous casting process of 65 Mn small square billet.Using the leica metallographic microscope to observe the macrostructure and inclusion morphology of LF refining,off-site and tundish,the inclusion type was determined by scanning electron microscopy.The test results showed that:(1)The main inclusions level in 65 Mn steel are below 10 μm,the most inclusions level of those is 0～5μm.(2)LF furnace has good narrow component control ability,which greatly reduces the content and grade of inclusions in steel.(3)The main inclusions before the refining are calcium aluminates,is brittle inclusions,has a large size of about 10μm.(4)After refining the main inclusions are manganese sulfides,with size less than 5μm,belong to plastic inclusions,can improve machinability.(5)The main inclusions in tundish are calcium sulfides with size less than 5μm,belong to class A inclusions.(6)Alumina and other elements form complex oxides,or small alumina inclusions.Figure45;Table17;Reference 64.