Nickel-Based Gadolinium Alloy for Neutron Adsorption Application in Ram Packages

Conference · Mon Sep 20 00:00:00 EDT 2004

OSTI ID:945165

Mizia, Ronald A. ^[1]; McConnell, Paul E. ^[1]; Robino, Charles Victor ^[1]

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1. Idaho National Engineering and Environmental Laboratory, Idaho Falls, ID (United States)

The National Spent Nuclear Fuel Program, located at the Idaho National Laboratory (INL), coordinates and integrates national efforts in management and disposal of US Department of Energy (DOE)-owned spent nuclear fuel. These management functions include development of standardized systems for long-term disposal in the proposed Yucca Mountain repository. Nuclear criticality control measures are needed in these systems to avoid restrictive fissile loading limits because of the enrichment and total quantity of fissile material in some types of the DOE spent nuclear fuel. This need is being addressed by development of corrosion-resistant, neutron-absorbing structural alloys for nuclear criticality control. This paper outlines results of a metallurgical development program that is investigating the alloying of gadolinium into a nickel-chromium-molybdenum alloy matrix. Gadolinium has been chosen as the neutron absorption alloying element due to its high thermal neutron absorption cross section and low solubility in the expected repository environment. The nickel-chromium-molybdenum alloy family was chosen for its known corrosion performance, mechanical properties, and weldability. The workflow of this program includes chemical composition definition, primary and secondary melting studies, ingot conversion processes, properties testing, and national consensus codes and standards work. The microstructural investigation of these alloys shows that the gadolinium addition is present in the alloy as a gadolinium-rich second phase. The mechanical strength values are similar to those expected for commercial Ni-Cr-Mo alloys. The alloys have been corrosion tested with acceptable results. The initial results of weldability tests have also been acceptable. Neutronic testing in a moderated critical array has generated favorable results. An American Society for Testing and Materials material specification has been issued for the alloy and a Code Case has been submitted to the American Society of Mechanical Engineers for code qualification.

• Research Organization: Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Idaho National Engineering and Environmental Laboratory, Idaho Falls, ID (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA), Nuclear Criticality Safety Program (NCSP)
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 945165
• Report Number(s): SAND2004-4462C
• Country of Publication: United States
• Language: English

Related Subjects

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
36 MATERIALS SCIENCE
98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL PROTECTION
ABSORPTION
ADSORPTION
ALLOYS
Alloy Microstructural Investigation
CHEMICAL COMPOSITION
CORROSION
CRITICALITY
CROSS SECTIONS
FISSILE MATERIALS
GADOLINIUM
GADOLINIUM ADDITIONS
GADOLINIUM ALLOYS
Gadolinium
Long-Term Disposal
MECHANICAL PROPERTIES
Metallurgical Development Program
NEUTRONS
NUCLEAR FUELS
National Spent Nuclear Fuel Program
Nuclear Criticality Control Measures
Nuclear Criticality Safety Program (NCSP)
Results
SOLUBILITY
SPECIFICATIONS
Spent Nuclear Fuel
Standardized Systems
TESTING
THERMAL NEUTRONS
Testing
WELDABILITY
YUCCA MOUNTAIN
Yucca Mountain Repository