2005 Volume 46 Issue 5 Pages 978-982
General equations allowing the determination of the elastic and dissipative energy contributions, as the function of the transformed fraction, ξ, to the martensitic transformation in shape memory alloys are derived. It is shown that the derivatives of these energies by ξ can be calculated from the measured hysteresis loops. It is illustrated, by the example of our previous experimental results obtained on CuAlNi shape memory alloys at different stress levels, σ, that our evaluation method gives consistent results with those obtained form the DSC measurements. Furthermore, the ξ- and σ-dependence of the above derivatives as well as their integral values for (0,1) and (1,0) ξ intervals, i.e. the dissipated energy and the elastic energy stored and released during the forward and reverse transformations, are determined as the function of stress.
