Rad hardness tests Sept 2003 u u u

· Rad hardness tests – Sept. 2003 u u u Capacitor assemblies Thermal glue (optional) capacitor barrel sealant · Two separate samples: u u At Georgia Tech – Co 60 source, 20 Mrad At N. C. State – reactor, ~50 years LHC Duke University ATLAS TRT Sept. 2003

· Production Capacitors: u u u Novacap 1808 N 821 K 202 NX n 1808 smaller than previous Johanson 1812 n Nominal 820 p. F, actual ~875 n ~8000 assemblies already produced, uncoated 15 in each radiation sample: n 5 with HV experience n 10 fresh, coated with Loctite Hysol PC 18 M Results: n No observed effect of radiation n ~10 n. A @ 2750 V for 10 assemblies + fixture Duke University ATLAS TRT Sept. 2003

· Thermal Glue: u u CHO-THERM 1641, mostly Al 2 O 3 Thermal conductivity 0. 9 W/m-K · Looking for radiation induced: u u Change in thermal conductivity Loss of adhesion Duke University ATLAS TRT Sept. 2003

· Results: u u u Both types of irradiated samples slightly yellow No loss of adhesion to FR 4, aluminum, DTMROC, with or without primer Thermal conductivities (preliminary, thick samples not properly cured: n Co 60: <10% decrease in thermal conductivity n reactor: not yet measured Duke University ATLAS TRT Sept. 2003

· Capacitor barrel sealants u u u Hopefully won’t be needed 3 silicone RTV’s: n GE RTV 11 – 2 part, viscosity 11000 n GE RTV 160 – 1 part, viscosity 38000 n GE RTV 615 – 2 part, viscosity 4000 Samples: filled ULTEM capacitor barrels Duke University ATLAS TRT Sept. 2003

· Results: u u No effect from either irradiation RTV 11 sticks well, but is removable, with or without primer RTV 160 bonds to ULTEM RTV 615 very runny, slow curing, removable Duke University ATLAS TRT Sept. 2003