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Lead-free Solder Alloys: Enthalpies of formation of (Ag,Cu,Ni)-Sn binary alloys. U. Saeed, H. Flandorfer, H. Ipser. Institute of Inorganic Chemistry / Materials Chemistry University of Vienna. Contents. Introduction Experimental technique Enthalpy of solution
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Lead-free Solder Alloys: Enthalpies of formation of (Ag,Cu,Ni)-Sn binary alloys U. Saeed, H. Flandorfer, H. Ipser Institute of Inorganic Chemistry / Materials Chemistry University of Vienna
Contents • Introduction • Experimental technique • Enthalpy of solution • Enthalpy of formation • Summary
Introduction • Six binaries & four ternaries in Ag-Cu-Ni-Sn system • Binary IMCs in Ag-Sn, Cu-Sn, Ni-Sn systems • Extended ternary solubilities in Cu-Ni-Sn system • No ternary or quaternary IMCs formation Enthalpy of formation • Estimation of phase stability • Optimization of Thermodynamic datasets for CALPHAD • Theoretical calculations of physical properties
Cu-Sn Cu41Sn11 Cu3Sn Cu6Sn5 Ni-Sn Ni3Sn2 Ni3Sn4 Ni3Sn Intermetallics in binary systems Ag-Sn Ag4Sn Ag3Sn
Cu-Ni-Sn 600 °C Ni3Sn4 Ni3Sn2-HT Ni3Sn LT Cu3Sn () Cu3Sn- HT
Schematic of Calvet type HT1000 Calorimeter Automatic drop device
Heating Melting Mixing liquid solvent MT = Solution calorimetry xA(solid) + yB (solid) AXBy (Solid) DT = fH298(AxBy) = x∙solH(A) + y∙solH(B) - solH(AxBy)
fH of Ag-Sn & Cu-Sn IMCs Reference state: Solid
fH of NiSn IMCs Reference state: Solid
fH of ternary solubilities (Cu,Ni)3Sn4 (Cu,Ni)3Sn2- HT Reference state: Solid
fH of ternary solubilities (Cu,Ni)3Sn Reference state: Solid
Summary • Solution calorimetery technique was used • Reinvesitigation of enthalpy of formation of binary intermetallic compounds • Agreement with the previously presented of data • Enthalpy of formation of extended ternary solubilities in Cu-Ni-Sn system