بررسی بافت و رفتار سیلان گرم یک فولاد میکروآلیاژی در اثر نرم شدن استاتیکی در طی تغییرشکل گرم

نوع مقاله : علمی و پژوهشی

نویسندگان

1 دانشگاه آزاد اسلامی واحد دزفول

2 دانشگاه اراک

چکیده

در این تحقیق، تاثیر پارامترهای ترمومکانیکی، تحولات متالورژیکی و بافت کریستالی بر رفتار سیلان گرم یک فولاد میکروآلیاژی مورد استفاده در لوله‌های انتقال گاز بررسی شده است. بدین منظور، آزمایشهای مختلف فشار گرم در محدوده دمایی850- 950 درجه سانتیگراد و تحت مقادیر مختلف کرنش، نرخ کرنش و زمان نگهداری پس از تغییرشکل، انجام شد. ریزساختار و بافت کریستالی نمونه‌های تغییرشکل یافته نیز به کمک میکروسکوپ الکترونی روبشی و تفرق الکترونهای برگشتی بررسی شد. نتایج نشان داد که دما و میزان کرنش در نرم شدن جزئی یا کامل نمونه‌ها نقش اساسی داشته و تشکیل رسوبات عناصر میکروآلیاژی در طی آنیل، این مساله را تحت تاثیر قرار می‌دهد.

کلیدواژه‌ها


عنوان مقاله [English]

Study of Texture and Warm Flow Stress of a Microalloyed Steel Due to Static Softening During Hot Deformation

نویسندگان [English]

  • Mostafa Mansourinejad 1
  • Bahman Mirzakhani 2
1 Islamic Azad University, Dezful Branch
2 Arak University
چکیده [English]

In this paper, the influences of metallurgical phenomena and texture in addition to the thermomechanical parameters on the warm flow stress of austenite in a gas line-pipe microalloyed steel have been investigated. Warm compression tests were carried out in the temperature range of 850 to 950˚C under various amounts of strain, strain rates and holding times. The microstructure and texture of the samples were then investigated by scanning electron microscopy and electron back scatter diffraction technique. The results indicated that deformation temperature and strain via strain induce precipitation of microalloying elements during annealing impose the fraction of recrystallization in the material.

کلیدواژه‌ها [English]

  • Static Softening
  • Austenite
  • Microalloyed Steel
  • Stress relaxation
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