Effects of Ausforming on Microstructure and Damping Capacity of Fe-Mn Alloy

The effects of pre-deformation at different temperatures on microstructure and damping capacity of Fe-Mn alloy have been studied. The microstructure was observed using optical microscope and TEM. The damping capacity was measured using reversal torsion pendulum with free decay method. The results showed that when deformed at R.T., the damping capacity of Fe-Mn alloy increased with the increasing deformation, and reached the maximum at 4% deformation. The ausforming deteriorated the damping capacity of Fe-Mn alloy. And with the deformation increasing, the damping capacity of Fe-Mn alloy decreased constantly. The right amount of deformation is benefit to the damping capacity of Fe-Mn alloy due to the increasing of stacking faults when the deformation temperature is blow the As temperature. But when the deformation temperature is higher than Af temperature, the formation of grid-like e-martensite reduced the mobility of the damping sources of Fe-Mn alloy, and the damping capacity decreased significantly.