Suresh, K. S. Kim, Dong-Ik Bhaumik, S. K. Suwas, Satyam 2024-01-20T10:34:42Z 2024-01-20T10:34:42Z 2021-09-05 2014-01 0966-9795 https://pubs.kist.re.kr/handle/201004/127271 Ni49.4Ti38.6Hf12 shape memory alloy has been characterized for structure, microstructure and transformation temperatures. The microstructure of the as-cast sample consists of B19' and R-phases, and (Ti,Hf)(2)Ni precipitate phase along the grain boundaries in the form of dendrites. The microstructure of the solution treated sample contains only B19' martensite phase, whereas a second heat treatment after solutionizing results in reappearance of the R-phase and the (Ti,Hf)(2)Ni grain boundary precipitate phase in the microstructure. A detailed microstructural examination shows the presence of precipitates having both coherent and incoherent interface with the matrix, the type of interface being dictated by the crystallographic orientation of the matrix phase. The present study shows that the (Ti,Hf)(2)Ni precipitates having coherent interface with the matrix, drive the formation of the R-phase in the microstructure. (C) 2013 Elsevier Ltd. All rights reserved. English ELSEVIER SCI LTD MARTENSITIC-TRANSFORMATION R-PHASE HF CU BEHAVIOR SURFACE Evolution and stability of phases in a high temperature shape memory alloy Ni49.4Ti38.6Hf12 Article 10.1016/j.intermet.2013.08.005 1 INTERMETALLICS, v.44, pp.18 - 25 INTERMETALLICS 44 18 25 scie scopus 000326910600003 2-s2.0-84883865595 Chemistry, Physical Materials Science, Multidisciplinary Metallurgy & Metallurgical Engineering Chemistry Materials Science Metallurgy & Metallurgical Engineering Article MARTENSITIC-TRANSFORMATION R-PHASE HF CU BEHAVIOR SURFACE Intermetallics, miscellaneous Shape-memory effects Martensitic transformations Microstructure Phase interfaces Electron microscopy, scanning