روش جدید در فراوری فولاد کم‌کربن با ساختار دوپلکس مارتنزیتی-فریتی

نوع مقاله : علمی و پژوهشی

نویسندگان

1 دانشگاه صنعتی سهند

2 دانشگاه مراغه

چکیده

در تحقیق حاضر یک نوع فولاد ساده کربنی با درصد وزنی کربن 033/0 تا دماهای مختلفی در ناحیه پایداری فاز آستنیت گرم شده و تحت اعمال فشار بالا، به صورت پیوسته از این ناحیه تا دمای محیط سرد شد. در نتیجه اعمال این فرایند، ساختاری شامل 80% مارتنزیت لایه ای و 20% فریت حاصل شد. نتایج حاصل نشان داد که تاثیر تغییرات فشار هیدرواستاتیکی بر روی دمای تعادلی شروع استحاله آستنیت به فریت (Ar3) عامل تشکیل حجم بالای فاز مارتنزیت در این فولاد بوده است. در نهایت مکانیزم فرایند تشکیل مارتنزیت در این فولاد کم کربن به صورت شماتیک تشریح شد.

کلیدواژه‌ها


عنوان مقاله [English]

Novel Procedure for Production of Duplex Martensitic-Ferritic Plain Low Carbon Steels

نویسندگان [English]

  • mehdi shaban ghazani 1
  • hossein shokrvash 2
1 sahand university of technology
2 maragheh university
چکیده [English]

In the present study, plain low carbon steel with 0.033 wt.% carbon content was subjected to severe pressure during continuous cooling from austenite region. The pressure was increased gradually and then suddenly released. As a result, a microstructure composed of 80% lath martensite and 20% ferrite was produced. Results showed that the martensite formation is not only a function of the cooling rate but also the hydrostatic pressure which effects the austenite to ferrite transformation start temperature (Ar3).

کلیدواژه‌ها [English]

  • Plain Low Carbon steel
  • Duplex Microstructure
  • martensite
  • Cooling Under pressure
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