PHASE-DIAGRAMS OF BINARY-SYSTEM HOCL3-MCL (N) (M=LI, MG, CA, PB, N=1,2)

The phase diagrams of binary system HoCl3-MCl(n) (M=Li, Mg, Ca, Pb; n= 1, 2) were investigated by means of DTA and X-ray diffraction analysis . It was found that HoCl3-LiCl system is of peritectic type with compo und Li3HoCl6 and invariant points e (50.5mol%HoCl3, 452 degrees C) as well as p (34.0mol%HoCl3, 506 degrees C). HoCl3-MgCl2, CaCl2, and PbCl 2 systems are of simple eutectic type with eutectic points 50.0mol%HoC l3(580 degrees C), 49.0mol%HoCl3(541 degrees C) and 37.0mol%HoCl3(422 degrees C) respectively. Unstable compound, formed in the solid state, is PbHoCl5 and decomposes at 408 degrees C. Some rules of phase diagr am were explored.