Martensite evolution and strain maps of compressed Austempered Ductile Iron samples until different plastic strain

Austempered Ductile Iron (ADI) is a cast iron with high potential to substitute cast steel due to the lighter weight, higher tensile strength and significantly lower manufacturing cost. This material has a microstructure consist of acicular ferrite and high carbon enriched retained austenite which will to partially transform to martensite under plastic deformation. During the conventional compression tests, the samples present a barrelling effect which is produced by the friction between platens and samples. This generates a triaxial stress state different from the ideal uniaxial stress condition. We propose to determinate the evolution of martensite fraction and the strain field on ADI compressed samples under different plastic strain using Energy-selective neutron imaging.