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The Tritium Research Laboratory (TRL) is a multi-user facility dedicated to studying the interactions of hydrogen isotopes with fusion materials. With its classification as a low-hazard, non-nuclear facility, the TRL is permitted to have an inventory up to 900 curies of tritium, 2 kg of depleted uranium, or 30 x 10-3 curies of activated metal specimens.

The TRL is comprised of the following test systems:

1. Ion Implantation/Thermal Desorption System

   This system (Figure 1) consists of a small, electrostatic ion accelerator coupled to a magnetic mass-separation stage, a deceleration stage, a target chamber, a thermal-desorption chamber and sample-handling equipment. The accelerator/beam transport system can produce mass-separated, positive ion beams of hydrogen or deuterium with energies between 200 and 10 keV per ion. At the highest beam energy, the maximum particle flux is 1 x 1020 ions/m2-s.

   

   Figure 1: View of Thermal Desorption Experiment

   Both the target chamber and desorption chamber are equipped with sample holders (Figure 2) that have the capability of heating specimens from the ambient temperature to 1200 K. This heating of the sample is controlled and there are quadrupole mass spectrometers (QMS) available for gas analysis. A rotary/linear motion feed-through is used to transfer specimens from one holder to the other or to a vacuum load lock. These feed-throughs are required to maintain the high quality vacuum of the system.

   

   Figure 2: Implantation Sample Holder

   This system is presently configured to investigate deuterium retention, release, and permeation properties for fusion-relevant, plasma facing component (PFC) materials.

2. Ultra High Vacuum (UHV) Annealing Oven

   The system consists of an evacuated Mellen tube furnace that is equipped with a 40 mm diameter by 250 mm length quartz tube liner. The heated zone is approximately 100 mm in length. Fabricated from high purity molybdenum, the sample holder can be used with specimens of dimensions up to 30 mm wide by 15 mm high by 40 mm long. Specimen temperatures are measured with thermocouples that are attached to the sample holder. These thermocouples have a measurement range between 27 and 1077°C. A QMS is used for analysis of the gases released from specimens during heating.

   The UHV annealing oven is used for specimen annealing and thermal-desorption, gas-release measurements.

3. Gas Analysis System

   This system is comprised of four key components: (1) an UHV test chamber, (2) quartz-tube heater that is surrounded by an induction coil, (3) capacitance manometers for pressure measurements, and (4) a quadrupole mass spectrometer for gas analysis. Linear motion translators transfer specimens from a sample load lock to the heat zone of the system.

   Induction-heating is used to rapidly heat specimens from ambient temperature to 1077° C. Absolute quantities of the gases released from the heated specimens are resolved to the 0.1 to 1.0 nanomole level for hydrogen and 0.01 to 0.1 nanomole level for inert gases. The pressure rise technique is used for resolving the different gases. Absolute pressures and volumes are obtained from capacitance manometer measurements. Gas species identification is obtained from QMS measurements via an aperture sampling arrangement.