Good point, however, the solder joint I am concerned with is attaching a
Kovar connector into an aluminum housing -- no FR4 is involved.  Still the
"new" solder compound being created could be a concern.  Sheila @ TRACOR AES

At 01:28 PM 10/23/97 -0400, you wrote:
>Dave, Sheila,
>Although soldering irons can certainly melt the 95/5 solder isn't there
>an increased risk of damage to the board because of the application of
>the higher temperature to the FR-4?
>Bev Christian
>Nortel
>[log in to unmask]
>
>>----------
>>From:  David D Hillman[SMTP:[log in to unmask]]
>>Sent:  Thursday, October 23, 1997 11:59 AM
>>To:    [log in to unmask]
>>Subject:       Re: [TN] [TECHNET] ASSY: Solder compatibility
>>
>>Hi Sheila - a  question - do you know that the voids are detrimental to
>>solder joint reliability? Also mixing of 95/5 with Sn62 is probably not
>>going to give you an intermetallic issue but you will probably get a
>>reeeaallly neat solder joint composition which will be very hard to predict
>>any type of properities data or even a simple melting point. If you must do
>>touchup why not use 95/5 as the touchup alloy? Soldering irons can melt
>>that alloy.  Good Luck.
>>
>>Dave Hillman
>>Rockwell Collins
>>[log in to unmask]
>>
>>
>>
>>
>>
>>[log in to unmask] on 10/21/97 10:05:36 AM
>>
>>Please respond to [log in to unmask]; Please respond to [log in to unmask]
>>
>>To:   [log in to unmask]
>>cc:    (bcc: David D Hillman/CedarRapids/Collins/Rockwell)
>>Subject:  [TECHNET] ASSY:  Solder compatibility
>>
>>
>>
>>
>>Hello TechNet ..
>>Does anyone have any experience with possible intermetallics formation if I
>>use Sn62Pb362Ag to touchup voids in a Vapor phase reflowed Sn95Sb5 solder
>>joint ???  Especially after 100 temp cycles from -55C to 120C?  Thanks for
>>any help!
>>Sheila Smith, Tracor AES
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