Hi Wei Hung,
For the SIR test on the soldering flux, the test board has two orientation
to pass the soldering wave at the pot.
a. Comb down
Means that the comb pattern of copper track would be soldered when touching
the wave. It is similar to our normal soldering of production board
(bottom side)
b. Comb up
Means that the comb pattern of copper track face up when passing the
preheator and touching the wave. Therefore, the copper track is not
soldered but only conditioned by he topside preheat during the conveypr
transfer and heat transmission from the bottom of the board during the
contact of soldering wave. It is intended to simulate the condition that
the flux is sprayed on the top surface of the board.
IPC-TM-650 is the procedure no. for the test procedure stated in IPC /
J-STD requirement. 2.6.3.3 is the section no. which specifiy the certain
test such as SIR. They can be downloaded from www.ipc.org website
SC-10 is an environmental friendly cleaner. The SIR method is based on
2.6.3.3 but not exactly the same. It is because 2.6.3.3 is basically used
in flux (including core wire, solder paste, wavesoldering flux). The
preparation procedure of the test board for cleaner should be different
from the flux type. After the test board is prepared, the test environment
(85% RH, 85 deg. c, 7 days, test voltage 100V, bias voltage 48V) and the
following procedure would be the same between the cleaner and the flux .
How to prepare the test board for cleaner ? Typically, it should be used
similar to how to use the cleaner in your typical production environment.
For example, if the cleaner is used in ultrasonic cleaning for 5 min and
then using force air drying at 85 deg. C for 2 min. You can prepare the
test board for cleaner using the one similar to your ultrasonic cleaning
procedure in this case
When using the cleaner, it should go through the course of evaparation at
ambient temperature or heated environment. The residue of the cleaner
should be very very low. Therefore, in typical case, you should get the
high SIR value like the bare board. No concern to me about reliability of
the cleaner standalone. However, it is other story if your SIR test is
targeted at to see whether the cleaner is effectively to clean the flux.
If the cleaner is not effective, the residual flux residue may cause low
SIR value.
Jackson Chan
Technical Services Manager
Cookson Electronics - Alpha Metals (Hong Kong)
Low cost , reliable alloy SACX0807
wasionhw
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Subject
2008/07/24 下午 [TGA] 清洗剂的测试
04:41
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wasionhw
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各位好,请教一个问题
在IPC-TM-650中,经常再现"Comb pattern down/up",这两个是什么意思,梳状电极
是上、下互为一组的.
另外，我在看一份SC-10的技术资料，资料中说到该清洗剂做了SIR测试，采用的
方法就是TM中的2。6。3。3
清洗剂的SIR测试是带偏压测试的吗？因为这引伸到一个问题：就是清洗后的梳形
电极，在高温高湿及加电的情况下
是否会一定会发生电迁移现象。
谢谢指点
WeiHuang 08/07/24
Changsha Weisheng Electronics Co.,Ltd
Changsha Willfar Information Technology Co.,Ltd
Add:National Class High-New-tech Industrial Development
Zone,Changsha,Hunan,P.R.China
Postcode:410013
TEL:0731-8619409
FAX:0731-8619439
Email:[log in to unmask]
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