DJR,
        IN A PREVIOUS INCARNATION I DID DESIGNS FOR A SIMILAR ENVIROMENT.  
     YOU DIDN'T SPECIFY WHAT KIND OF WIRE; INSULATED, STRANDED, 
     UNINSULATED, ETC.  IF IT'S AN INSULATED STYLE WIRE I WOULD RECCOMEND 
     USING TERMINALS OR CONNECTORS TO MOUNT IT.  IT SOUNDS AS IF THE HEAT 
     APPLIED TO MELT THE SILVER SOLDER IS CAUSING A THERMAL SHOCK TO THE 
     HOLE.  MAKE SURE YOU HAVE PADS ON ALL LAYERS TO SUPPORT THE HOLE AND 
     MAKE SURE THE ASSEMBLER DOESN'T TOUCH THE BOARD WITH THE SOLDERING 
     IRON.  IF IT'S A WIRE FOR WIRE BONDING I'M ALL OUT OF SUGGESTIONS.
     
     ROBERT BUTTERWORTH
     SR PWB DESIGNER
     ADC VIDEO SYSTEMS
     11 FARFIELD BLVD
     WALLINGFORD, CT
     [log in to unmask]


______________________________ Reply Separator _________________________________
Subject: High Temp PCB
Author:  [log in to unmask] at internet-mail
Date:    6/21/96 8:55 PM


I currently have a customer with an application requiring a 6 layer PCB 
that must exist in a 120 degrees C environment. They are currently using 
silver solder to attach wires to the PCB, and the holes are failing. Did I 
mention there is also a lot of vibration? 
     
Does anyone know of a successful fab stategy, i.e. PCB laminate, plating 
and soldercoat combination that can successfully survive these conditions? 
     
We have been considering using rivets in the holes as a parallel solution.
     
All comments are welcome.
     
djr