Change in stacking-fault energy with Mn content and its influence on the damping capacity of the austenitic phase in Fe-high Mn alloys

The effect of Mn content on the damping capacity of gamma austenitic phase for Fe-(17-28)%Mn alloys has been studied in relation to the stacking-fault energy (SFE), on the basis of the results of microstructural observations, thermodynamic calculations and vibration tests in a torsional mode. The da mping capacity of gamma austenite decreases with the increase in the Mn con tent. The decrease in density of stacking-faults in gamma austenite and mob ility of the stacking-fault boundary, on which the damping capacity of gamm a phase depends, is considered to be responsible for the deterioration of d amping capacity. (C) 1999 Kluwer Academic Publishers.