Effects of Rolling Pass Schedule for Recrystallization Behavior in the Arctic Offshore Steels by Thermo-Mechanical Control Processing (TMCP)

摘要

This paper focuses on the recrystallization behavior to get lowtemperature Charpy V-notch toughness at -60 °C. Combination of TypeI - Static Recrystallization and Type II - No Recrystallization, Type ⅢMetadynamic (Partial) / Dynamic Recrystallization (simply Type Ⅲcan be a mixture of Type I and Type II occurring at the same time)behavior is very important because austenite grain size depends onType I and final grain size is affected by Type II & Type Ⅲ highly. Inthis study, high mean flow stress and reduction ratio per pass werecompared at finish rolling process. Our finding is to use steels at articoffshore structure until -60 °C, high mean flow stress is more effectivethan high reduction ratio per pass in rolling pass schedule because ofthe grain refinement by the partial dynamic recrystallization at finishrolling stage.