Part II. Surface tension measurements on binary phosphates
JSGT 1959 V43 T325-T336
The surface tensions of some simple binary phosphate melts have been measured, using a maximum pull on cylinder method. This method is an adaption of the de Noi.iey ring method, in which the ring is replaced by a hollow platinum cylinder. The effects of composition and temperature upon the surface tension of melts in the systems Na2O–P2O5, K2O–P2O5 and CaO–P2O5 have been studied in some detail. Surface tension–composition relationships have been found to be linear in all cases. The results obtained have indicated a relationship between surface tension and its temperature coefficient and the extent of electrical interaction between the cation and the phosphate lattice, as measured by the ion–oxygen attraction parameter Ze2/R. The development of a theory for these observed relationships, and for similar relationships which have been reported for the binary silicates, has enabled some comparison of the liquid structures to be made.
B. T. Bradbury & W. R. Maddocks
