Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9796032 | Materials Science and Engineering: A | 2005 | 11 Pages |
Abstract
In recent years, several studies on grain refinement of ferrite have been conducted by different methods (equal channel angular pressing (ECAP), high pressure torsion (HPT), accumulative roll bonding (ARB)) in order to optimize the relationship between mechanical properties and microstructure of steels. The present work deals with the strain-induced dynamic transformation of ferrite. Samples of low C-Mn and Nb-Ti microalloyed steels were intensively deformed in warm torsion. This resulted in the formation of ultrafine ferrite grains (â¼1 μm) thereby enhancing the mechanical properties compared to the ordinary hot rolled products without the necessity of implementing an extremely high strain accumulation. The following annealing has resulted in recrystallization and growth of ferrite grains accompanied by a homogenization of the final microstructure and a decrease in hardness. With increase in annealing time the volume fraction of martensite/austenite (MA) constituent increased. The results have shown that the effect of steel chemistry was insignificant in comparison with the effect of thermomechanical processing parameters.
Related Topics
Physical Sciences and Engineering
Materials Science
Materials Science (General)
Authors
G. Azevedo, R. Barbosa, E.V. Pereloma, D.B. Santos,