Phase equilibria in the Gd-Ti-Ge system at 1070 K

Physico-chemical analysis techniques, including X-ray phase analysis, elect ron probe X-ray analysis and metallographic analysis, were employed in cons tructing the isothermal section of the Gd-Ti-Ge system at 1070 K. The forma tion of the following ternary intermetallic compounds was detected in the G d-Ti-Ge system at 1070 K: GdTiGe (high-temperature modification of the CeFe Si structure type, space group P4/nmm, a=0.4060(1) nm, c=0.7708(1) nm; low- temperature modification of the CeScSi structure type, space group I4/mmm, a=0.4060(1) nm, c=1.5412(1) nn) and Gd2Ti3Ge4 (Sm5Ge4 structure type, space group Pnma, a=0.7044(1) nm, b=1.3494(3) nm, c=0.7187(2) nm). Differential thermal analysis was employed to investigate the melting temperature of RTi Ge compounds (R=Gd-Tm). The melting temperatures of RTiGe compounds are pro portional to the melting temperatures of the rare earths. (C) 1999 Elsevier Science S.A. All rights reserved.