Microstructure and Thermoelastic Martensitic Transformations in Ni-Mn-Al Based Alloys

Abstract

The physical properties and structure, thermoelastic martensitic transformations (TMT's) of Ni50Mn50−xAlx alloys (x=0-25) were studied by the methods of resistomeyry and durametry, transmission and scaning electron microscopy (TEM and SEM), and X-ray diffraction analysis. It has been shown that the critical temperatures of TMT's are found to be decrease with increasing aluminum content, and the structure of martensite changes: 2M(L10) and multilayered 10M and 14M. Martensite has a hierarchic packet morphology of coherent plates of nano- and submicrocrystalline crystals with habit boundaries close to {110}B2.