In this paper, the effect of Zn element addition on martensitic transformation
and damping capacity of Mn–20Cu–5Ni–2Fe (at%, M2052) alloy has been
investigated systematically by using X-ray diffraction, optical microscopy, and
dynamic mechanical analyzer. The results show that martensitic transformation
and damping capacity have a crucial dependence on the addition of Zn element.
It not only can markedly enhance the damping capacity of M2052 alloy at room
temperature (internal friction Q
1 increases by 23% compared to M2052
without Zn as strain amplitude reaches 410
4), but also reduces the
attenuation of damping capacity effectively at elevated temperatures. This is
mainly because the addition of Zn element can evidently increase the Gibbs
free energy difference between g parent phase and g’ phase produced by face
centered cubic to face centered tetragonal (f.c.c-f.c.t) phase transformation, and
then raises the martensitic transformation and its reverse transformation
temperatures, eventually leading to the apparent increase of amount of f.c.t g’
phase micro-twins as damping source and the significant enhancement of
damping capacity. It will be of great value for design and optimization of highperformance
M2052 damping alloy toward practical applications.