Transformation behavior of Ti-Ni-Cu-Mo alloys

Abstract

Transformation behaviors of Ti-(47 - x)Ni-3.0Cu-xMo (at.%) (x = 0.3-1.0) alloys were investigated by means of electrical resistivity measurements and X-ray diffraction. The alloy with Mo-content of 0.3 at.% transformed in one-stage i.e., B2-B19', while the alloy with Mo-content of 0.5 at.% transformed in two-stage i.e., B2-R-B19'. The alloys with Mo-content more than 0.7 at.% transformed in three-stage i.e., B2-R-B19-B19'. M-s (the B19' martensite formation temperature), A,, (the B 19 martensite formation temperature) and T-R is (the R phase formation temperature) decreased with increasing Mo-content. The decreasing rate of M-s, M-s(') and T-R with increasing Mo-content were found to be 60 K/at.% Mo, 27 K/at.% Mo and 20 K/at.% Mo, respectively. The Mo-content dependence of transformation behaviors in Ti-(47 - x)Ni-3.0Cu-xMo alloys were ascribed to the different Mo-content dependence of M-s,, AT and TR. (c) 2006 Elsevier B.V. All rights reserved.