The stacking fault probability and damping capacity of Fe–19Mn, Fe–17Mn–2Cr and Fe–19Mn–1.5Si alloys were studied. The stacking fault probability and volume fraction of ε-martensite were determined by using X-ray powder diffraction. The damping capacity was measured by using a reversal torsion pendulum. The microstructure was observed using optical and transmission electron microscopy. The results indicated that the damping capacity of the alloys increased almost linearly with increasing strain amplitude. This could be explained by using the breakaway model of Shockley partial dislocations. Thus, Si could increase the stacking fault probability and the number of Shockley partial dislocations in Fe–Mn alloy, but it decreased the damping capacity because it introduced enough distortion of the lattice to pin down the movement of Shockley partial dislocations. The Cr also decreased the damping capacity of Fe–Mn alloy, but its effect was not greater than that of Si. This was because the distortion of the lattice after adding Cr was less serious than after adding Si.

Effect of Si and Cr on Stacking Fault Probability and Damping Capacity of Fe-Mn Alloy. S.K.Huang, N.Li, Y.H.Wen, J.Teng, S.Ding, Y.G.Xu: Materials Science and Engineering A, 2008, 479[1-2], 223-8