Lead-free Solder Alloys: Enthalpies of Lead-free Solder Alloys: Enthalpies of formation of (Ag,Cu,Ni)-Sn formation of (Ag,Cu,Ni)-Sn
binary alloysbinary alloys
U. Saeed, H. Flandorfer, H. Ipser
Institute of Inorganic Chemistry / Materials Chemistry
University of Vienna
Introduction
Experimental technique
Enthalpy of solution
Enthalpy of formation
Summary
Contents
Estimation of phase stability
Optimization of Thermodynamic datasets for CALPHAD
Theoretical calculations of physical properties
Introduction
Enthalpy of formation
Binary IMCs in Ag-Sn, Cu-Sn, Ni-Sn systems
Extended ternary solubilities in Cu-Ni-Sn system
No ternary or quaternary IMCs formation
Six binaries & four ternaries in Ag-Cu-Ni-Sn system
Cu-Sn
Cu41Sn11
Cu6Sn5
Cu3Sn
Ni-Sn
Ni3Sn4
Ni3Sn2
Ni3Sn
Ag-Sn
Ag4SnAg3Sn
Intermetallics in binary systems
Cu-Ni-Sn
600 °C
Cu0 10 20 30 40 50 60 70 80 90 100
Sn
0
10
20
30
40
50
60
70
80
90
100
Ni
0
10
20
30
40
50
60
70
80
90
100
Single Phase Multiphase
Cu3Sn ()
Ni3Sn4
Ni3Sn2-HT
Ni3Sn LT
Cu3Sn- HT
Schematic of Calvet type HT1000 Calorimeter
Automatic drop device
xA(solid) + yB (solid) AXBy (Solid) DT
fH298(AxBy) = x∙solH(A) + y∙solH(B) - solH(AxBy)
Solution calorimetrySolution calorimetry
=
Sol
mixfus
MT
DTp dTC=
liquid solvent MT
Heating
Melting
Mixing
Enthalpy of solution
xCu0.36Ni0.24Sn0.40
0.00 0.01 0.02 0.03 0.04 0.05 0.06 so
lH
kJ
/mo
l
18
20
22
24
26
28
30
32
mol/Jk 27.29sol
xAg
0.14 0.16 0.18 0.20 0.22 0.24 0.26 0.28
fH
k
J/m
ol
-5.5
-5.0
-4.5
-4.0
-3.5
-3.0
-2.5
-2.0
-1.5
Experimental results KleppaLauri
Ag4Sn
Ag3Sn
xCu
0.50 0.55 0.60 0.65 0.70 0.75 0.80 0.85
fH
kJ/m
ol
-10
-9
-8
-7
-6
-5
-4
Expeimental resultsGanguleeKleppaBiltzCohen (Cu3Sn)
Cu41Sn11
Cu3Sn
Cu6Sn5
fH of Ag-Sn & Cu-Sn IMCs
Reference state: Solid
fH of NiSn IMCs
xNi
0.40 0.45 0.50 0.55 0.60 0.65 0.70 0.75 0.80
fH
kJ
/mo
l
-45
-40
-35
-30
-25
-20
-15
Experimental resultsKoerberDannöhlPredelTorgersenVassilev
Ni3Sn4
Ni3Sn2(HT)
Ni3Sn(LT)
Reference state: Solid
fH of ternary solubilities
(Cu,Ni)3Sn2- HT (Cu,Ni)3Sn4
xCu
0.00 0.10 0.20 0.30 0.40
fH
k
J/m
ol
-40
-35
-30
-25
-20
-15
xSn=0.40
Reference state: Solid
xCu
0.00 0.01 0.02 0.03 0.04 0.05 0.06 fH
J
/mo
l
-30
-28
-26
-24
-22
-20
xSn= 0.58
fH of ternary solubilities
(Cu,Ni)3Sn
xCu
0.0 0.2 0.4 0.6 0.8
fH
kJ/m
ol
-35
-30
-25
-20
-15
-10
-5
xSn = 0.25
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
Thanks for paying attention