Surface Tension of the Molten CaO-SiO2 Binary and CaO-SiO2-Al2O3 Ternary Systems

Th e surJace tension oj the moLten CaO -Si0 2 binmy and CaO-S i0 2 - AI 2 0 3 ternmy ~ys tem at 1550° and 1 600°C has been measured by means oj a maximum bubbLe pressure method.Th e measured values give the Jollowing expressionsJor the sUlface tension , )"c, in dynes /Jer centimeter:where N i means the moLe Jraction oj com/Jonent i.The reLative error in the surface tension was estimated to be within one /Jercent, which is cons iderably smaller than that invoLved in other works on the surface tension oj sLags.The temperature co1Jicient oj the surface tension oj the CaO-Si0 2 binmy system increased with increase oj silica content Jrom negative va Lue to positive vaLue at about 58 mol% oj S i0 2 , ranging in -0.2 to + 0.06 dynes/cm .degree.The reLation between the obtained sUlface tension and the ionic jJotential is disCllssed.The causes of eX/Jerimen taL errors are intensively discussed, concluding the estimation oj the /necise bubble diameter as the most im/Jortant calise oj errors.The detaiLed discription oj the careJuL jJ reliminory experimen t to increase the accuracy in the meosllrments is included. Ph ilbrook 8l Kojima! O ) 1 550 GrPresen t wo rk 1600 Ar Pt + 20 % Rh