Effect of Thermal Cycling (γ<->ε) on Martensitic Transformation Kinetics and Damping Capacity of Fe –17mass%Mn Alloy
Effect of thermal cycling(γ↔ε) on γ→ε martensitic transformation kinetics and damping capacity of Fe-17mass%Mn alloy has been studied. The amount of ε martensite increases with thermal cycling in spite of decrease in Ms temperature. The increase in ε martensite content with thermal cycling is attributable to an increase in the density of martensite nucleation sites by introduction of dislocations during thermal cycling. The γ→ε martensitic transformation kinetics shows a burst mode in the non-cycled specimen, while the kinetics exhibits a sigmoidal mode in the cycled specimens. The damping capacity of the alloy increases with increasing the ε martensite content in the non-cycled specimen. On the contrary, the damping capacity of the alloy decreases with increasing the ε martensite content in the cycled specimens. The reason is that the dislocations introduced during thermal cycling, which obstruct the movement of the damping sources, become more with thermal cycling.
N. Igata and S. Takeuchi
Y. K. Lee et al., "Effect of Thermal Cycling (γ<->ε) on Martensitic Transformation Kinetics and Damping Capacity of Fe –17mass%Mn Alloy", Key Engineering Materials, Vol. 319, pp. 59-66, 2006