A brand new way of looking into Martensitic Transformation in Intercritically Austempered Ductile Iron: in light of Neutron Diffraction. With Neutron diffraction, it is possible to examine the total test volume and examine the transformation in real-time. Alongside calculation of specific critical stress and strain at transformation for each tested material, examination of the inter-granular and intra-granular stresses was carried out. The development of residual stresses during deformation and the elastic diffraction constants for both the ferrite and austenite phases were also determined. This book can serve as a handbook for a typical experimental procedure of a neutron diffraction experiment and a step by step data analysis regime to come to the desired data. This book also has a comprehensive set of tables with diffraction elastic constants for most of the crystallographic direction in all the phases for all the examined chemistry, which is crucial for modelling purposes.