X-Ray Diffraction Studies on Ti-Pd Shape Memory Alloys

Abstract

The phase transformation behavior of Ti-50Pd-5x (x =Zr, Hf, V, Nb, Ta, Cr, Mo, W) (at.%) alloys was studied by X-ray diffraction measurements from room temperature to 800 oC. In all the alloys, B19 martensite was observed at room temperature and it transformed to B2 phase upon heating. In addition, peaks corresponding to formation of (Ti, x)2Pd3 phase was seen for all the alloys. However, the temperature of formation of (Ti, x)2Pd3, interestingly, varied with respect to the elements group from the periodic table. Elements except from group IV (Zr and Hf) have been identified to accelerate the formation of (Ti, x)2Pd3 phase even at low temperatures (~400 oC).