2006 Volume 47 Issue 4 Pages 1209-1213
The effect of 3d-transition-metal alloying on the phase constitution of Ti-18 mol%Nb based shape memory alloys was investigated by X-ray diffraction analysis (XRD) at room temperature. The baseline binary Ti-18 mol%Nb alloy (called Binary) and ternary Ti-18 mol%Nb-3 mol%X alloys (X=V, Cr, Mn, Fe, Co and Ni, called 3X) were fabricated by Ar arc-melting method, followed by homogenization at 1273 K for 3.6 ks. These alloys were cold-rolled with 30% and 98% reduction in thickness. Some specimens from 98% cold rolled material were solution treated at 1273 K for 1.8 ks and quenched in water. It was found that the phase present in the solution-treated and quenched Binary and 3V was α″ martensite phase and that of the other alloys was β phase. No other phase or ordering was confirmed in these baseline and 3X alloys. The lattice parameter of β phase showed a good correlation with the Goldschmidt atom radius of the ternary alloying metals. It was confirmed that (1) almost same type of deformation texture was formed in β phase materials regardless of the alloying metals but that (2) the development of recrystallization texture was suggested to be different depending on the alloying metals.
