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Article: Relationship between austenite dislocation density introduced during thermal cycling and M(s) temperature in an Fe-17 Wt Pct Mn alloy
- Article from:
- Metallurgical and Materials Transactions
- Article date:
- July 1, 2002
- Author:
CopyrightCopyright Minerals, Metals & Materials Society Jul 2002. Provided by ProQuest LLC. (Hide copyright information)
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The reason why thermal cycling decreases the martensite start (M^subS^) temperature of an Fe-17 wt pct Mn alloy was quantitatively investigated, based on the nucleation model of E martensite and a thermodynamic model for a martensitic transformation. The M^subS^ temperature decreased by about 22 K after nine cycles between 303 and 573 K, due to the increase in shear-strain energy (deltaG^subsh^) required to advance the transformation dislocations through dislocation forests formed in austenite during thermal cycling. The deltaAG^subsh^ value increased from 19.3 to 28.8 MJ/m^sup3^ due to the increase in austenite dislocation density from 1.5 X 10^sup12^ to 3.8 X 10^sup13^/m^sup2^ with the ...