Effect of Y addition on microstructure and martensitic transformation of a Ni-rich Ti-Ni shape memory alloy

• Published in: Journal of materials science 2007-07, Vol.42 (14), p.5791-5794
• Main Authors: LIU, A. L, SUI, J. H, LEI, Y. C, CAI, W, GAO, Z. Y, ZHAO, L. C
• Format: Article
• Language: English
• Subjects: Alloying additive; Cross-disciplinary physics: materials science; rheology; Differential scanning calorimetry; Diffraction; Electronics; Exact sciences and technology; Martensite; Martensitic transformations; Materials science; Microstructure; Optical microscopes; Other topics in materials science; Phase transitions; Physics; Rare earth metals; Shape memory alloys; Ternary alloys; Ternary systems; Titanium base alloys; Transformation temperature
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1007/s10853-006-0558-x

In the present work, 1 at% Y was added to Ti-50.7at%Ni alloy to prepare Ti-50.2Ni-1Y alloy and the effects of rare earth Y addition on the microstructure and martensitic transformation behavior of Ti-50.7at%Ni alloy was investigated by optical microscope, scanning electronic microscope (SEM) X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The results show the microstructure of Ti-50.2Ni-1Y alloy is different with that of Ti-50.7at.%Ni alloy, and its microstructure consists of B19′martensite and the Y-rich phase, which may be YNi phase. One-step martensitic transformation occurs in Ti-50.2Ni-1Y ternary alloy. The phase transformation temperatures increase rapidly with Y addition, and the increase of Ms is about 85°C.