Isothermal section of the Nd–Co–Ti ternary system at 500°C

Abstract

Abstract The isothermal section of the Nd–Co–Ti system at 500 °C has been investigated by means of XRD and SEM/EDS techniques. Compound Nd2Co3 was observed to exist at 500 °C with the orthorhombic La2Ni3-type structure, space group Cmca and unit cell parameters a = 0.4986(2) nm, b = 1.0000(2) nm, c = 0.7546(2) nm. One ternary compound NdTixCo12−x with the tetragonal ThMn12-type structure (space group I4/mmm) was found with a homogeneity range of 1.43 ≤ x ≤ 1.82, i.e. 11–14 at.% Ti. The structure of NdTi1.7Co10.3 was determined by Rietveld refinement method with the unit cell parameters a = 0.84616 (1) nm, c = 0.47447 (1) nm. The maximum solid solubilities of Ti in Nd2Co17, Nd2Co7, NdCo3, NdCo2, and Nd3Co are 6, 1.5, 2, 4 and 2 at.%, respectively.