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1. 1. Does Bainite form with or without diffusion? : The experimental and theoretical evidence

   Författare :Peter Kolmskog; Annika Borgenstam; John Ågren; Bevis Hutchinson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Carbon steels; Bainite; Bainitic ferrite; Widmanstätten ferrite; Microstructure; Microscopy; Thermodynamic modeling;

   Sammanfattning : With the increased interest in bainitic steels, fundamental understanding of the bainite transformationis of major importance. Unfortunately, the research on bainite has been hampered by an oldcontroversy on its formation mechanism. Over the years two quite different theories have developedclaiming to describe the bainite transformation i.e. LÄS MER

3. 2. Formation of Bainite in Steels

   Författare :Jiaqing Yin; Annika Borgenstam; Bevis Hutchinson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fe-C alloys; Bainitic transformation; Proeutectoid ferrite; Upper bainite; Lower bainite; Morphology; Steels.; Teknisk materialvetenskap; Materials Science and Engineering;

   Sammanfattning : A systematic survey of morphology of bainite and proeutectoid ferrite was carried out in order to validate some old thoughts of bainite transformation mechanism. It is confirmed that there is no morphological evidence supporting a sharp change neither between Widmanstätten ferrite and the ferritic component of upper bainite, nor between upper and lower bainite. LÄS MER

4. 3. Formation of Bainite Studied by In-situ High-energy X-ray Diffraction

   Författare :Sen Lin; Peter Hedström; Annika Borgenstam; Sébastien Allain; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Steel; Bainitic transformation; High-energy X-ray diffraction; Electron microscopy; Carbon diffusion; Thermodynamics and kinetics; Microstructure evolution; 高强钢; 贝氏体转变; 原位高能X射线衍射; 扫描与透射电子显微镜; 碳扩散; 热力学与动力学; 微观结构表征; Stål; Bainitiska fasomvandlingen; Högenergi-röntgendiffraktion; Elektronmikroskopi; Koldiffusion; Termodynamik och kinetik; Mikrostrukturutveckling; Materials Science and Engineering; Teknisk materialvetenskap;

   Sammanfattning :       Bainitic steels have attracted great attentions in recent years due to their excellent combination of properties to accommodate a wide range of applications. A deep and comprehensive understanding of how bainite forms is required to better design the production process and optimize the properties of bainitic steels. LÄS MER

5. 4. On the role of microstructure in wear of nanostructured carbide-free bainitic steels

   Författare :Pouria Valizadeh Moghaddam; Jens Hardell; Esa Vuorinen; Braham Prakash; Mikael Olsson; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Tribology; Wear; Microstructure; Carbide-free bainite; Nanostructured; Retained austenite; Steel; High temperature; Machine Elements; Maskinelement;

   Sammanfattning : The significance of steel production for the development of sustainable society and economy is immense. Today’s fast growing global economy poses an increasing demand for improving the properties of steel. LÄS MER

7. 5. Wear and fatigue properties of isothermally treated high-Si steels

   Författare :Alejandro Leiro; Peter Hedström; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materialteknik; Engineering Materials; Centrumbildning - Centrum för högpresterande stål CHS ; Centre - Centre for High Performance Steel CHS ;

   Sammanfattning : In recent years steels containing Si contents of 1,5% or more have been isothermally transformed in order to obtain a microstructure consisting of bainitic ferrite laths and retained austenite. The refined microstructure and presence of retained austenite has allowed the manufacture of steels with high tensile strength and considerable elongation. LÄS MER