Construction of apparatus for curing by electron irradiation and its characteristics

An apparatus was designed and constructed for electron irradiation curing treatments of organic silicone fibers as the precursor of silicon carbide (SiC) fibers. Using the apparatus, the organic silicone fibers were cured by electron beam crosslinking, and the active species formed were quenched by heating up to 1173 K (900degC) in oxygen free atmosphere. This apparatus is composed of two sample trays, irradiation chamber, middle container, heating container, electric furnace, and vacuum pump. The sample tray is moved from irradiation chamber to heating container through the middle container. Irradiation chamber, middle container and heating container are separated by airtight shutters. It was observed that the air leak is negligible, and the oxidation was well prevented during the radiation curing. The absorbed dose was 14.4 kGy per double pass by using electron beam of 2MeV and 1mA with 100 cm/min of sample tray moving speed. The temperature rise of sample by electron irradiation was depressed by Helium gas flow and with the supply of liquid nitrogen to the radiator inside of irradiation container. The temperature in the heating container showed rather large distribution at the higher temperature. (author)