Hi out there.
I have been looking quite a while for a high-temperature potting material that can stand 260 deg. C operating. It must have a relatively high mechanical strength (also at 260 deg. C) and a temperature coefficient preferrably below 50 ppm/deg. K.
I have been loking at quite a few epoxies but their TC becomes normally quite high above Tg - and for very high temperature epoxies Tg seems to be quite low (125 deg. C or lower).
Regards
Morten Hammer
Senior Engineer (EE)
Dantec Dynamics A/S
Denmark