Inmodernindustry,thedevelopingtendencyandprospectforproductionsoftheoil andgaspipelinesteelsistofurtherimprovethestrength andtoughnessbyadvancedmanufactureprocessofthethermo-mechanicalcontrol process(TMCP)torefinemicrostructure.Inthiswork,thehot deformationbehavioraswellasitseffectonthephasetransformationoftheclean acicularferritepipelinesteelwithsimplechemicalcomposition hasbeeninvestigated.Accordingtotheresult,