2018 | AFC ACCOMPLISHMENTS 173 Project Description TheTCM will provide a new capability for the measurement of thermal properties of irradiated samples. Thermal conductivity and thermal diffusivity are among the most important properties of a nuclear fuel, but they can also be one of the most difficult to measure.TheTCM provides micron-level thermal property information that is commensurate with microstructure heterogeneity. The development of theTCM connects closely with INL’s larger PIE effort to provide new validation metrics for fundamental computational material science models. A prototype TCM instrument was designed and tested during FY16.Work for FY 17 centered on developing ancillary equipment to support standalone remote operation in preparation for installation in the Irradiated Materials Characterization Laboratory (IMCL) and initiation of equipment qualification.The primary tasks included, 1- development of cell feedthroughs for both optical and electrical signals, 2 – design and construction of a film thickness monitor, 3 – development of an equipment qualification plan, 4 – develop an integrated equipment rack to house lasers and instrumentation, and 5 – develop coding instrumentation software for controlling the TCM. Accomplishments Several accomplishments were realized in the development of the TCM during FY17. Using the standard glove box panel, a layout for the electrical and optical feedthroughs was developed. Feedthroughs were incorporated into standard vacuum fittings to meet leak rate requirements and for ease of installation and replacement if necessary.Vendors for the feedthroughs were identified and the fittings were procured and tested. The ability of the TCM to directly measure thermal conductivity requires a thin gold film to be applied to the sample.The film thickness is an important parameter that must be measured. A unique film thickness monitor was developed which allows film thickness to be determined based on light transmission.This device was designed and fabricated for use in a hot cell using remote manipulators for sample placement. The TCM provides micron-level thermal property information that is commensurate with microstructure heterogeneity. The TCM will allow for a direct comparison between microstructure and material properties without the need to upscale modeling results to length scales associated with current experimental capability. The development of the TCM connects closely with INL’s larger PIE effort to provide new validation metrics for fundamental computational material science models.