IPC-4556 印制板化学镍钯浸金（ENEPIG）规范ENG - 第46页
IPC-4556-a5-10 Figure A5-10 Example of the W etting Performance for a Nominal 8 µin Electroless Palladium T ested with SAC305 Solder Sample 14 1.42Au/7.48Pd/297.04Ni Fr(mN/mm) Standard : NF-A-89 400P t(s) 0.25 0.20 0.15 …
IPC-4556-a5-8
Figure A5-8 Example of the Wetting Performance for a Nominal 20 µin Electroless Palladium Tested with SnPb Solder
Sample 19 1.48Au/17.95Pd/196.17Ni
Fr(mN/mm)
Standard : NF-A-89 400P
t(s)
0.25
0.20
0.15
0.10
0.05
0.00
-0.05
-0.10
-0.15
-0.20
12345678910
-0.25
IPC-4556-a5-9
Figure A5-9 Example of the Wetting Performance for a Nominal 4 µin Electroless Palladium Tested with SAC305 Solder
Sample 13 2.22Au/4.39Pd/280.83Ni
Fr(mN/mm)
Standard : NF-A-89 400P
t(s)
0.25
0.20
0.15
0.10
0.05
0.00
-0.05
-0.10
-0.15
-0.20
12345678910
-0.25
January 2013 IPC-4556
35
IPC-4556-a5-10
Figure A5-10 Example of the Wetting Performance for a Nominal 8 µin Electroless Palladium Tested with SAC305 Solder
Sample 14 1.42Au/7.48Pd/297.04Ni
Fr(mN/mm)
Standard : NF-A-89 400P
t(s)
0.25
0.20
0.15
0.10
0.05
0.00
-0.05
-0.10
-0.15
-0.20
12345678910
-0.25
IPC-4556-a5-11
Figure A5-11 Example of the Wetting Performance for a Nominal 12 µin Palladium Tested with SAC305 Solder
Sample 15 1.78Au/10.03Pd/300.79Ni
Fr(mN/mm)
Standard : NF-A-89 400P
t(s)
0.25
0.20
0.15
0.10
0.05
0.00
-0.05
-0.10
-0.15
-0.20
12345678910
-0.25
IPC-4556 January 2013
36
通
通
通
重
：
薄
Summary of solderability testing of ENEPIG samples in as-received condition:
1) The wetting times for SnPb solder ranged between 1 and 2 seconds, while those for SAC305 were typically below 1
second - this reduction in wetting times is attributed to the increased solder pot temperature used for SAC testing
2) The majority of SnPb tested samples showed a continual rise to the final wetting force, some sample groups reached
their maximum force after five seconds and then leveled out.
3) For the SAC test groups, the time to reach the maximum force was reduced by 1 to 2 seconds and the shape of the
curve was flatter overall
4) There were no failures in any of the test groups and most samples showed excellent intra-group consistency.
5) Samples tested with 8+ months of ‘‘natural’’ shelf life performed better than some newer samples with similar gold and
palladium thicknesses.
To evaluate the robustness of the ENEPIG deposits, wetting balance coupons were stressed using a protocol of 8 hours of
72 °C [162 °F]/85% R.H exposure. The wetting balance coupons were sent to Continental’s Seguin Texas location where
the wetting balance coupons and the solder spread coupons were stressed together in a single chamber in one stressing cycle,
in order to reduce variability. Following stressing, the wetting balance samples were returned to S T and S for completion
of testing. No additional baking was done on the stressed coupons prior to testing. The previously used protocol was used
for testing with SAC305 and Eutectic SnPb.
IPC-4556-a5-12
Figure A5-12 Example of a Nominal 4 µin Electroless Palladium ENEPIG Post Temperature and Humidity Stressing, Tested
with SnPb - Showing Excellent Robustness
Sample 16 1.33Au/3.80Pd/181.65Ni
post 8 hours @72C/85% R.H.
Fr(mN/mm)
Standard : NF-A-89 400P
t(s)
0.25
0.20
0.15
0.10
0.05
0.00
-0.05
-0.10
-0.15
-0.20
12345678910
-0.25
January 2013 IPC-4556
37