Fundamental study of deformation and fatigue fracture behavior of solder alloys under complex load conditions is a key to enabling implementation of sophisticated three-dimensional (3D) time-dependent nonlinear finite-element stress and strain analyses for the life assessment for electronic packages and assemblies. In this study, the rate-dependent deformation and fatigue fracture behavior of Sn3.8Ag0.7CuPb-free alloy and SnPb eutectic alloy was investigated with thin-walled specimens using a biaxial servo-controlled tension–torsion material testing system, with solder alloys subjected to a variety of complex load conditions: pure shearing at strain rates between 6.7×107s and 1.3×101s, creep at temperatures ranging from room temperature up to 125°C, and cyclic loading with frequencies of 0.001Hz to 3Hz. Biaxial stress conditions were imposed to investigate the effects of multiaxial stresses on deformation behavior. The effects of frequency and temperature on cyclic deformation and fatigue facture were investigated for lead-free Sn3.8Ag0.7Cu and SnPb eutectic solder. Fractography of fatigue tested samples was also conducted to determine possible fatigue failure mechanisms.

1.
Frear
,
D. R.
,
Burchett
,
S. N.
, and
Morgan
,
H. S.
, 1994,
The Mechanics of Solder Alloy Interconnects
,
D. R.
Frear
,
S. N.
Burchett
,
H. S.
Morgan
, and
J. H.
Lau
, eds.,
Van Nostrand Reinhold
, New York, pp.
1
6
.
2.
Liang
,
J.
,
Dariavach
,
N.
, and
Shangguan
,
D.
, 2006, “
Solidification Condition Effects on Microstructures and Creep Resistance of Sn-3.8ag-0.7Cu Lead-Free Solder
,”
Metall. Mater. Trans. A
1073-5623, to be published.
3.
Hwang
,
J. S.
, 1996, “
Modern Solder Technology for Competitive Electronics Manufacturing
,
McGraw–Hill
, New York.
4.
Stouffer
,
D. C.
, and
Dame
,
L. T.
, 1996,
Inelastic Deformation of Metals: Models, Mechanical Properties, and Metallurgy
,
Wiley
, New York.
5.
Morris
,
J. W.
, Jr
,
Song
,
H. G.
, and
Hua
,
F.
, 2002, “
Creep Properties of Lead-free Solder Joints
,”
Proceedings UCLA Workshop on Pb-Free Solder
,
UCLA
, Los Angeles, CA.
6.
Krempl
,
E.
, 1982,
Mechanical Testing for Deformation Model Development
,
R. W.
Rohde
and
J. C.
Swearenger
, eds.,
ASTM
, New York, Paper No. ASTM STP 765, pp.
5
28
.
7.
Heinrich
,
S. M.
,
Shakya
,
S.
,
Lee
,
P. S.
, and
Liang
,
J.
, 2002, “
Analytical Expressions for Shear and Axial Joint Deformations in Area-Array Assemblies Due to Global CTE Mismatch
,”
Proceedings of IMECE2002 ASME International Mechanical Engineering Congress & Exposition
,
New Orleans
, LA.
8.
Gittus
,
J. H.
, 1975,
Creep, Viscoelasticity and Creep Fracture in Solids
,
Wiley
, New York.
9.
Orowan
,
E.
, 1946, “
Dislocations in Metals
,” edited by
Morris
Cohen
,
American Institute of Mining and Metallurgical Engineers
, Institute of Metals Division,
NY
, 1954.
10.
Riedel
,
H.
, 1986,
Fracture at High Temperatures
,
Springer
, New York.
11.
Liang
,
J.
,
Gollhardt
,
N.
,
Lee
,
P. S.
,
Schroeder
,
S. A.
, and
Morris
,
W. L.
, 1996, “
A Study of Fatigue and Creep Behaviour of Four High Temperature Solders
,”
Fatigue Fract. Eng. Mater. Struct.
8756-758X,
19
, pp.
1401
1409
.
12.
Ochoa
,
F.
,
Deng
,
X.
, and
Chawla
,
N.
, 2004,
J. Electron. Mater.
0361-5235,
33
, pp.
1596
1607
.
13.
Hull
,
D.
, and
Bacon
,
D. J.
, 2001,
Introduction to Dislocation
,
4th ed.
,
Butterworth-Heinemann
, Oxford, UK.
14.
Johnston
,
W. G.
, and
Gilman
,
J. J.
, 1959, “
Dislocation Velocities, Dislocation Densities, and Plastic Flow in Lithium Fluoride Crystals
,”
J. Appl. Phys.
0021-8979,
30
, pp.
129
144
.
15.
Liang
,
J.
,
Gollhardt
,
N.
,
Lee
,
P. S.
,
Schroeder
,
S. A.
, and
Morris
,
W. L.
, 1997, “
Creep Study for Fatigue Life Assessment of Two Lead-Free High Temperature Solder Alloys
,”
Mater. Res. Soc. Symp. Proc.
0272-9172,
445
, pp.
307
312
.
You do not currently have access to this content.