The Ag–Bi–In system: enthalpy of formation

The Ag–Bi–In ternary alloys as lead-free solder candidates in electronic industry were studied. Using a high temperature microcalorimeter, the enthalpy of formation of this system was determined along six isoplethic sections (xBi/xIn=1/4, 1/2, 1/1, 62/38, xAg/xBi=1/3 and xAg/xIn=1/1) in the temperature range of 809–911 K. A critical analysis of these results leads us to the following conclusion: the enthalpy of formation of the Ag–Bi–In liquid system (ΔmixHm(Ag–Bi–In)°=f(xAg,xBi)) can be correctly represented by the Toop relation on the entire ternary molar fraction range.