Staff Only

MSTD Coated Particle Fuel Development Laboratory

MSTD Coated Particle Fuel Development Laboratory: Lab-scale fabrication and full QC acceptance testing

John D. Hunn
Tel: 865.574.2480
Fax: 865.574.4186

The MSTD Coated Particle Fuel Development Laboratory was created to support the DOE Advanced Gas Reactor Fuel Development and Characterization (AGR) program. This laboratory houses coating and compact capabilities, as well as a vast assortment of characterization capabilities. This laboratory is designed to work with uranium bearing materials and has also been used for compacting fuel pellets from uranium bearing powders.




50 mm diameter fluidized bed coating furnace:

  • A 50 mm diameter fluidized bed coating furnace is used for coated particle fuel development activities. This lab-scale coater has been used to perform parametric studies to generate an improved understanding of the relationship between process and properties for the various layers in the tri-isotropic (TRISO) fuel design. The furnace was also used to produce the first high performance US manufactured TRISO particle fuel.

50 mm diameter fluidized bed coating furnace


Kernels fabricated


Overcoating compacting process:

  • An overcoating compacting process has been developed and optimized for producing the 12.5 mm diameter cylindrical fuel forms used by the AGR program. Studies are being performed to establish allowable range of packing fraction and matrix density. The overcoating process can also be used for other fuel compact forms, such as annular cylinders or spherical pebbles.
Overcoating compacting process

Coater simulated and modeled


Characterization procedures:

  • Characterization procedures have been developed to obtain data to meet all the standard Quality Control (QC) requirements for TRISO coated particle fuel. The methods developed include historically used approaches modified to take advantage of current technology improvements (such as computer automation), as well as completely new methods.

Particles and compacts characterized


Lab-scale fabrication and full QC acceptance testing:

Specific facility features, equipment, instruments used (as applicable):
  • 50 mm diameter fluidized bed CVD coating furnace
  • vibrational shape sorting table, sieves and rollermicrometers for particle sorting and classification
  • rotary riffler for random sampling
  • overcoating and compacting equipment
  • various furnaces for heat treatment up to 2000°C
  • computer automated optical microscopy
  • scanning electron microscopes with elemental analysis capability
  • materialographic equipment for mount, grinding and polishing specimen cross sections
  • liquid gradient density columns for coating density measurement
  • mercury porosimeter and gas pycnometer for density and porosity analysis
  • wet chemistry equipment for acid dissolution to measure uranium and impurity content
  • leach-burn-leach analysis for detection of defective fission product barriers
  • ellipsometry microscope for measurement of pyrocarbon anisotropy
  • high resolution x-ray microtomograph for non-destructive analysis of coated particles
Task Members:

Dixie Barker
Tel: 865.576.6485
Fax: 865.576.8424



Ivan Dunbar
Tel: 865.574.6309
Fax: 865.241.3650


Andrew Kercher
Tel: 865.576.3488
Fax: 865.576.8424


 Oak Ridge National Laboratory