Some Physico Chemical Properties Of Glasses In The System Znb2O4 -Rf2 (R=Mg,Ca,Sr,Ba)

Glasses were synthesised from chemically pure ZnB2O4, MgF2, SrF2, and BaF2 in vitro carbon crucibles, at 1050-1100C for 1 h in an Ar atm. The addition of MgF2 and CaF2 {25, SrF3 {30, and BaF2 {35%mol increased the crystallisation of the melt during casting. Addition of fluorides increased the density, nD, and a (linear thermal expansion coeff.) values and lowered the glass transition point. Both BaF2 and SrF2 decreased the viscosity.