In a message dated 7/6/98 4:38:32 PM Pacific Daylight Time,
[log in to unmask] writes:

> Technetters,
>
>  I'm working on a project that involves radiant heating of a circuit board.
>  I need to know the emmitance value for a standard FR-4 board with solder
>  mask.
>
>  None of my handbooks gives this value, and several internet searches turned
>  up nothing.  Can anyone help?
>

Hi Mark!

     Will thermal conductivity help you? Here's some typical figures:

Copper: 400 watt/minute per degree Kelvin
Ceramic: 18 watt/minute per degree Kelvin
Fiberglass (FR4): .4 watt/minute per degree Kelvin
Plastic: .2 watt/minute per degree Kelvin

-Steve Gregory-

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