A new ternary compound (Ni, Mn)2Ga in Ni-Mn-Ga system

A new ternary compound (Ni, Mn)(2)Ga was identified in Ni-Mn-Ga system by a combination of powder X-ray diffraction, differential thermal analysis and electron probe microanalysis. The (Ni, Mn)(2)Ga phase was determined with a Mn2Ge-type hexagonal structure, with lattice parameters of a = 4 1629(8) nm, c = 5 2983(9) nm, and unit cell volume of 0 07952(4) nm(3) after refinement The reversible phase transformation from (Ni, Mn)(2)Ga hexagonal structure to bcc (B2) cubic structure at high temperature was suggested by DTA measurements. The transformation peaking temperatures during heating and cooling are 834 0 degrees C and 815 8 degrees C for Mn40Ni25Ga35, 804 7 degrees C and 774 1 degrees C for Mn50Ni17Ga33, respectively (C) 2010 Elsevier Ltd All rights reserved.