Installation of the Irradiation Test Vehicle in the Advanced Test Reactor

The Irradiation Test Vehicle (ITV) was installed in the Department of Energy's Advanced Test Reactor (ATR) during May 1999. The ITV is capable of providing neutron spectral tailoring and individual temperature control for up to 15 experiment capsules simultaneously. The test vehicle consists of three permanently installed in-pile tubes running the length of the reactor vessel. The bores of these in-pile tubes are kept dry and test trains with integral instrumentation are inserted and removed through a transfer shield plate above the reactor vessel head. The test vehicle is designed to irradiate specimens as large as 2.2 cm in diameter, at temperatures of 250-800 C, achieving neutron damage rates as high as 10 displacements per atom per year in Vanadium. The experiment specimen temperature control is fully automated using a Distributed Control System (DCS) to control up to 15 separate blended gas channels for the ITV. The system remains in place as a permanent ATR Experiment support system and has excess capacity to accommodate experiment program growth. The ITV was initially installed with instrumented dummy tests to allow for testing and characterization of the control system.