As traditional lead-based solders are banned and replaced by lead-free solders, the drop impact reliability is becoming increasingly crucial because there is little understanding of mechanical behaviors of these lead-free solders at high strain rates. In this paper, mechanical properties of one lead-based solder, Sn37Pb, and two lead-free solders, Sn3.5Ag and Sn3.0Ag0.5Cu, were investigated at strain rates that ranged from 600s1 to 2200s1 by the split Hopkinson pressure and tensile bar technique. At high strain rates, tensile strengths of lead-free solders are about 1.5 times greater than that of the Sn37Pb solder, and also their ductility are significantly greater than that of the Sn37Pb. Based on the experimental data, strain rate dependent Johnson–Cook models for the three solders were derived and employed to predict behaviors of solder joints in a board level electronic package subjected to standard drop impact load. Results indicate that for the drop impact analysis of lead-free solder joints, the strain rate effect must be considered and rate-dependent material models of lead-free solders are indispensable.

1.
The European Parliament and The Council of the European Union
, 2003, “
Directive 2002/95/EC of the European Parliament and of the Council of 27 January 2003 on The Restriction of the Use of Certain Hazardous Substances in Electrical and Electronic Equipment (RoHS)
,”
Official Journal of the European Union
,
L37
, pp.
19
23
.
2.
Zeng
,
K.
, and
Tu
,
K. N.
, 2002, “
Six Cases of Reliability Study of Pb-Free Solder Joints in Electronic Packaging Technology
,”
Mater. Sci. Eng. R.
0927-796X,
38
, pp.
55
105
.
3.
Pang
,
J. H. L.
, and
Che
,
F. X.
, 2006, “
Drop Impact Analysis of Sn-Ag-Cu Solder Joints Using Dynamic High Strain Rate Plastic Strain as Impact Damage Driving Force
,”
IEEE Proceedings of the 56th Electronic Components an Technology Conference
, San Diego, CA, May 30–Jun. 2, pp.
49
54
.
4.
Suh
,
D.
,
Kim
,
D. W.
,
Liu
,
P.
,
Kim
,
H.
,
J. A.
,
Weninger
,
Kumar
,
C. M.
,
Prasad
,
A.
,
Grimsley
,
B. W.
, and
Tejada
,
H. B.
, 2007, “
Effects of Ag Content on Fracture Resistance of Sn-Ag-Cu Lead-Free Solders Under High-Strain Rate Conditions
,”
Mater. Sci. Eng., A
0921-5093,
460–461
, pp.
595
603
.
5.
Rao
,
R. T.
,
Rymaszewski
,
E. J.
, and
Klopfenstein
,
A. G.
, 1997,
Microelectronics Packaging Handbook
, 2nd ed.,
Chapman and Hall
,
New York
.
6.
JEDEC Solid State Technology Association
, 2003, “
Board Level Drop Test Method of Components for Handheld Electronic Products
,” Arlington, Jul., JESD22-B111.
7.
Date
,
M.
,
Shoji
,
T.
,
Fujiyoshi
,
M.
, et al.
, 2004, “
Impact Reliability of Solder Joints
,”
Proceedings of the 54th Electronic Components and Technology Conference
,
IEEE
,
New York
, pp.
668
674
.
8.
Wang
,
B.
, and
Yi
,
S.
, 2002, “
Dynamic Plastic Behavior of 63wt%Sn37wt%Pb Eutectic Solder Under High Strain Rate
,”
J. Mater. Sci. Lett.
0261-8028,
21
, pp.
697
698
.
9.
Siviour
,
C. R.
,
Walley
,
S. M.
,
Proud
,
W. G.
, and
Field
,
J. E.
, 2005, “
Mechanical Properties of SnPb and Lead-Free Solders at High Rates of Strain
,”
J. Phys. D: Appl. Phys.
0022-3727,
38
(
22
), pp.
4131
4139
.
10.
Wong
,
E. H.
,
Selvanayagam
,
C. S.
,
Seah
,
S. K. W.
,
van Driel
,
W. D.
,
Caers
,
J. F. J. M.
,
Zhao
,
X. J.
,
Owens
,
N.
,
Tan
,
L. C.
,
Frear
,
D. R.
,
Leoni
,
M.
,
Lai
,
Y. S.
, and
Yeah
,
C. L.
, 2008, “
Stress-Strain Characteristics of Tin-Based Solder Alloys for Drop-Impact Modeling
,”
J. Electron. Mater.
0361-5235,
37
(
6
), pp.
829
836
.
11.
Darveaux
,
R.
, and
Banerji
,
K.
, 1992, “
Constitutive Relations for Tin-Based Solder Joints
,”
IEEE Trans. Compon., Hybrids, Manuf. Technol.
0148-6411,
15
(
6
), pp.
1013
1024
.
12.
Shi
,
X. Q.
,
Zhou
,
W. H.
,
Pang
,
L. J.
, and
Wang
,
Z. P.
, 1999, “
Effect of Temperature and Strain Rate on Mechanical Properties of 63Sn/37Pb Solder Alloy
,”
ASME J. Electron. Packag.
1043-7398,
121
(
3
), pp.
179
185
.
13.
Wilde
,
J.
,
Becker
,
K.
,
Thoben
,
M.
,
Blum
,
W.
,
Jupitz
,
T.
,
Wang
,
G. Z.
, and
Cheng
,
Z. N.
, 2000, “
Rate Dependent Constitutive Relations Based on Anand Model for 92.5Pb5Sn2.5Ag Solder
,”
IEEE Trans. Adv. Packag.
1521-3323,
23
(
3
), pp.
408
414
.
14.
Amagai
,
M.
,
Watanabe
,
M.
,
Omiya
,
M.
,
Kishimoto
,
K.
, and
Shibuya
,
T.
, 2002, “
Mechanical Characterization of Sn-Ag-Based Lead-Free Solders
,”
Microelectron. Reliab.
0026-2714,
42
(
6
), pp.
951
966
.
15.
Plumbridge
,
W. J.
, and
Gagg
,
C. R.
, 1999, “
Effects of Strain Rate and Temperature on the Stress-Strain Response of Solder Alloys
,”
J. Mater. Sci.: Mater. Electron.
0957-4522,
10
, pp.
461
468
.
16.
Kim
,
K. S.
,
Huh
,
S. H.
, and
Suganuma
,
K.
, 2002, “
Effects of Cooling Speed on Microstructure and Tensile Properties of Sn-Ag-Cu Alloys
,”
Mater. Sci. Eng., A
0921-5093,
333
(
1–2
), pp.
106
114
.
17.
Nose
,
H.
,
Sakane
,
M.
, and
Tsukada
,
Y.
, 2003, “
Temperature and Strain Rate Effects on Tensile Strength and Inelastic Constitutive Relationship of SnPb Solders
,”
ASME J. Electron. Packag.
1043-7398,
125
, pp.
59
66
.
18.
Shohji
,
I.
,
Yoshida
,
T.
,
Takahashi
,
T.
, and
Hioki
,
S.
, 2004, “
Tensile Properties of Sn-Ag Based Lead-Free Solders and Strain Rate Sensitivity
,”
Mater. Sci. Eng., A
0921-5093,
366
, pp.
50
55
.
19.
Liang
,
J.
,
Dariavach
,
N.
, and
Shangguan
,
D.
, 2005, “
Deformation Behavior of Solder Alloys Under Variable Strain Rate Shearing & Creep Conditions
,”
Proceedings of the Tenth International Symposium on Advanced Packaging Materials: Processes, Properties and Interfaces
, Mar. 16–18,
IEEE
,
Irvine, CA
, pp.
21
26
.
20.
Pang
,
J. H. L.
, and
Xiong
,
B. S.
, 2005, “
Mechanical Properties for 95.5Sn-3.8Ag-0.7Cu Lead-Free Solder Alloy
,”
IEEE Trans. Compon. Packag. Technol.
1521-3331,
28
(
4
), pp.
830
840
.
21.
Zhu
,
F.
,
Zhang
,
H.
,
Guan
,
R.
, and
Liu
,
S.
, 2007, “
The Effect of Temperature and Strain Rate on the Tensile Properties of a Sn99.3Cu0.7(Ni) Lead-Free Solder Alloy
,”
Microelectron. Eng.
0167-9317,
84
, pp.
144
150
.
22.
Liang
,
J.
,
Dariavach
,
N.
,
Callahan
,
P.
, and
Shangguan
,
D.
, 2007, “
Inelastic Deformation and Fatigue of Solder Alloys Under Complicated Load Conditions
,”
ASME J. Electron. Packag.
1043-7398,
129
, pp.
195
204
.
23.
Andersson
,
C.
,
Sun
,
P.
, and
Liu
,
J.
, 2008, “
Tensile Properties and Microstructural Characterization of Sn-0.7Cu-0.4Co Bulk Solder Alloy for Electronics Applications
,”
J. Alloys Compd.
0925-8388,
457
, pp.
97
105
.
24.
Hopkinson
,
B.
, 1914, “
A Method of Measuring the Pressure Produced in the Impact of Bullets
,”
Philos. Trans. R. Soc. London, Ser. A
0962-8428,
213
, pp.
437
456
.
25.
Lee
,
S. W. R.
, and
Dai
,
L. H.
, 2001, “
Characterization of Strain Rate-Dependent Behavior of 63Sn-37Pb Solder Using Split Hopkinson Torsional Bars
,”
Proceedings of the 13th Symposium on Mechanics of SMT & Photonic Structures
, ASME International Mechanical Engineering Congress & Exposition, New York, pp.
1
6
.
26.
Wang
,
B.
, 2006, “
Dynamic Strength of Eutectic Solders
,” private communication.
27.
Tee
,
T. Y.
,
Ng
,
H. S.
,
Lim
,
C. T.
,
Pek
,
E.
, and
Zhong
,
Z. W.
, 2004, “
Impact Life Prediction Modeling of TFBGA Packages Under Board Level Drop Test
,”
Microelectron. Reliab.
0026-2714,
44
(
7
), pp.
1131
1142
.
28.
Chong
,
D. Y. R.
,
Che
,
F. X.
,
Pang
,
J. H. L.
,
Ng
,
K.
,
Tan
,
J. Y. N.
, and
Low
,
P. T. H.
, 2006, “
Drop Impact Reliability Testing for Lead-Free and Lead-Based Solder IC Packages
,”
Microelectron. Reliab.
0026-2714,
46
, pp.
1160
171
.
29.
Tsai
,
T. Y.
,
Yeh
,
C. L.
,
Lai
,
Y. S.
, and
Chen
,
R. S.
, 2007, “
Transient Submodeling Analysis for Board-Level Drop Tests of Electronic Packages
,”
IEEE Trans. Electron. Packag. Manuf.
1521-334X,
30
(
1
), pp.
54
62
.
30.
Wiese
,
S.
, and
Rzepka
,
S.
, 2004, “
Time-Independent Elastic–Plastic Behavior of Solder Materials
,”
Microelectron. Reliab.
0026-2714,
44
(
12
), pp.
1893
1900
.
31.
Johnson
,
G. R.
, and
Cook
,
W. H.
, 1983, “
A Constitutive Model and Data for Metals Subjected to Large Strains, High Strain Rates and High Temperatures
,”
Proceedings of the Seventh International Symposium on Ballistics
, The Hague, The Netherlands, pp.
541
547
.
32.
Yadav
,
S.
, and
Ramesh
,
K. T.
, 1995, “
The Mechanical Properties of Tungsten-Based Composites at Very High Strain Rates
,”
Mater. Sci. Eng.
0025-5416,
A203
, pp.
140
153
.
33.
Umbrello
,
D.
,
Saoubi
,
R. M.
, and
Outeiro
,
J. C.
, 2007, “
The Influence of Johnson–Cook Material Constants on Finite Element Simulation of Machining of AISI 316L Steel
,”
Int. J. Mach. Tools Manuf.
0890-6955,
47
, pp.
462
470
.
34.
Dey
,
S.
,
Borvik
,
T.
,
Hopperstad
,
O. S.
, and
Langseth
,
M.
, 2007, “
On the Influence of Constitutive Relation in Projectile Impact of Steel Plate
,”
Int. J. Impact Eng.
0734-743X,
34
, pp.
464
486
.
35.
Follansbee
,
P. S.
, 1985, “
The Hopkinson Bar
,”
ASM Metals Handbook
, Vol.
8
,
ASM International
,
Materials Park, OH
, pp.
198
203
.
36.
Nicholas
,
T.
, 1981, “
Tensile Testing of Materials at High Rates of Strain
,”
Exp. Mech.
0014-4851,
21
(
5
), pp.
177
185
.
37.
Lindholm
,
U. S.
, 1964, “
Some Experiments With the Split-Hopkinson Pressure Bar
,”
J. Mech. Phys. Solids
0022-5096,
12
, pp.
317
335
.
38.
ABAQUS 6.5 User’s Manual
, 2004,
Hibbitt, Karlsson & Sorensen, Inc.
.
39.
Liang
,
R.
, and
Khan
,
A. S.
, 1999, “
A Critical Review of Experimental Results and Constitutive Models for BBC and FCC Metals Over a Wide Range of Strain Rates and Temperatures
,”
Int. J. Plast.
0749-6419,
15
(
9
), pp.
963
980
.
40.
Suhir
,
E.
, 1988, “
On a Paradoxical Phenomenon Related to Beams on Elastic Foundation: Could External Compliant Leads Reduce the Strength of a Surface-Mounted Device?
,”
ASME J. Appl. Mech.
0021-8936,
55
(
4
), pp.
818
821
.
41.
Wong
,
E. H.
, 2005, “
Dynamics of Board Level Drop Impact
,”
ASME J. Electron. Packag.
1043-7398,
127
, pp.
200
207
.
42.
Yeh
,
C. L.
,
Lai
,
Y. S.
, and
Kao
,
C. L.
, 2006, “
Evaluation of Board-Level Reliability of Electronic Packages Under Consecutive Drops
,”
Microelectron. Reliab.
0026-2714,
46
(
7
), pp.
1172
1182
.
43.
Tee
,
T. Y.
,
Luan
,
J.
,
Pek
,
E.
,
Lim
,
C. T.
, and
Zhong
,
Z.
, 2004, “
Novel Numerical and Experimental Analysis of Dynamic Responses Under Board Level Drop Test
,”
Proceedings of the Fifth International Conference on Thermal and Mechanical Simulation and Experiments in Microelectronics and Microsystems
, New York, pp.
133
140
.
44.
Tee
,
T. Y.
,
Luan
,
J.
,
Pek
,
E.
,
Lim
,
C. T.
, and
Zhong
,
Z.
, 2004, “
Advanced Experimental and Simulation Techniques for Analysis of Dynamic Responses During Drop Impact
,”
Proceedings of the 54th Electronic Components and Technology Conference
, Piscataway, NJ, pp.
1088
1094
.
You do not currently have access to this content.