Dave,

Sounds like thermal shock.  What you need to do is raise the temperature of
the component slowly before soldering, the higher the better.  Also, check
your soldering iron temperature if you are using an iron.

If you have a re-flow air stream, use it to heat the chip and
board.  Slowly heat the component and board to a temperature of 125 to 175
C.  Then re-flow or hand solder the part to the board.


Donald Kyle


At 09:27 AM 4/16/2002, you wrote:
>Hi folks! I have ran into a problem which has me baffled and the extra 20
>ounces of Coke I consumed this morning didn't bring about any better
>thought clarity so I would like to bounce the problem off the minds of
>TechNet. I have been attempting to hand solder a chip resistor (50 x 100)
>but have immediate cracking of the resistor across the width of the
>component. The resistor is either Aluminum Nitride or BeO (I'm still trying
>to find out which material). And yes, we are using proper soldering
>technique(s) and the resistor pad geometries are our standard dimensions. I
>know that the typical resistor body material is Alumina. Has anyone had
>good or bad experiences in hand soldering AlN or BeO resistors? Have I run
>into a material flexural strength issue?
>
>Dave Hillman
>Rockwell Collins
>[log in to unmask]
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