Investigation on the Microstructure, Texture and Magnetostriction of Directionally Solidified Tb0.3Dy0.7Fe1.95−xVx Alloys

Abstract

Effect of V addition on the microstructure and magnetostriction of directionally solidified Tb0.3Dy0.7Fe1.95 has been investigated. The microstructure of V added alloys (Tb0.3Dy0.7Fe1.95−xVx with x=0, 0.025, 0.05, and 0.075) indicate that Fe-50 at.% V is formed as primary phase, which subsequently undergoes spinodal decomposition. The spinodially decomposed Fe-rich phase reacts with the liquid and forms the matrix phase, (Tb,Dy)Fe2. The V-rich spinodally decomposed product, on the other hand, exists as remnant phase without undergoing any metallurgical transformation. Texture studies indicate that the grains of (Tb,Dy)Fe2 show 〈110〉/rotated 〈110〉 and 〈112〉 orientations for all compositions investigated in the directionally solidified condition. An improvement in magnetostriction has been noticed for small addition of V (x=0.025) and with further addition the magnetostrictive property decreases. The formation of additional phases containing vanadium is attributed to be the reason when V is added in higher concentration (x>0.025) levels.