it is rather simple and straightforward. The enthalpy of change per unit volume of the material is numerically equal to the area under the stress-strain hysteresis graph. Multiply that by the volume of the material and you have your answer.

I hope it helps.

I meant the total energy absorbed/released not just the work done.

I have experimental data where a shape memory wire went through a sudden transformation spurt and absorbed heat energy from the environment and then released it back into it. As the stretching of the wire coincided with the temperature drop and was followed by a contraction of the wire with a simultaneous temperature rise, when there was no heat source or sink present, it lead me to think that the transformation caused energy to be absorbed and then again released.

I should add that the experiment was done in water and the temperature of said water dropped about 5 °C in about 10 sec, while at the same time the wire elongated. All of that with no input from the outside. This is a dramatic temperature change for water with no other source for causing it. But that also causes me to doubt that there can be this much energy in the molecular bonds.

So if I could know the total energy and subtracted from it the energy used for the movement of the wire, I should get the amount of heat that was released during transformation. And then I can see if that energy could have caused this big a change in temperature.

In other words I need to know how big is the difference in energy, in the molecular bonds, between austenite and martensite, for a set volume of material. I think from that I should be able to at least estimate the energy that should have been absorbed/released.

Go through this paper. I hope it helps.

http://scitation.aip.org/content/aip/journal/apl/101/7/10.1063/1.4746257

Thank you that was most helpful.

I am not sure if it is relevant but I have some numerical values from a Ph.D. study for copper based SMAs of composition around Cu-15%Al-4%Ni.  Which can be used for a crude calculation, I hope,

Elif Tarhan, “AgeIng CharacterIstIcs of Copper Based Shape Memory Alloys”, Ph.D., METU, January 2004.

for  beta to martensite entalphy is  delta H = -8J/g        

for  martensite to beta   delta H = 7 J/g

difference in delta H is due to difference in transformation temperatures.

Cp    for Cu is 0.39  J/g  ,  for Ni it is 0.44 J/g          for the alloy assume Cp to be o.40 J/g

Since  delta H = Cp x delta T   ,  

 temperature  change due to heat of martensitic trnsformation  = 8 / 0.4  =20 K

Hope that I am not doing a mistake because this is much more than I would expect.

I think you have enough information from other researchers.

I would suggest to have a look at this paper - try compare the relative area of the curves