Abstract:
The local structural distortions arising as a consequence of increasing Mn content in Ni(2)Mn(1+x)In(1-x) (x=0, 0.3, 0.4, 0.5, and 0.6) and its effect on martensitic transformation have been studied using extended x-ray absorption fine structure (EXAFS) spectroscopy. Using the room temperature EXAFS at the Ni and Mn K-edges in the above compositions, the changes associated with respect to the local structure of these absorbing atoms are compared. It is seen that in the alloys exhibiting martensitic transformation (x more than or equal to 0.4) there is a significant difference between the Ni-In and Ni-Mn bond lengths even in the austenitic phase indicating atomic volume to be the main factor in inducing martensitic transformation in Ni-Mn-In Heusler alloys.