nonfissionable
Cannot be split
Nonfissionable describes material that cannot undergo nuclear fission—the splitting of atomic nuclei that releases enormous energy.
Most elements are nonfissionable; only certain isotopes like uranium-235 and plutonium-239 can sustain the chain reactions used in reactors and weapons.
The reactor core is surrounded by nonfissionable shielding material.
Secure and unchanging
- inertInactive, physically or chemically
- unreactiveNot prone to reactions
- nonreactiveChemically inactive substance
- subcriticalBelow critical mass
uranium-238 · depleted uranium · neutron absorption · transmutation · long-lived
Processed nuclear byproduct, very dense
- thoriumActinide, atomic number ninety
- uranium-238Predominant uranium isotope
- actinideHeavy radioactive metal series
- heavy metalAggressive amplified rock genre
dense · metallic · armor plating · counterweight · ballast · penetrator · cladding · industrial applications
Controlled fission apparatus
- criticalityState of utmost importance
- chain reactionSelf-sustaining causal sequence
- fertileAble to reproduce abundantly
- enrichmentImprovement through addition
nuclear fuel cycle · spent fuel · transmutation · cross-section · nuclear physics · radioactive decay
stable
Secure and unchanging
- inertInactive, physically or chemically
- unreactiveNot prone to reactions
- nonreactiveChemically inactive substance
subcritical · uranium-238 · depleted uranium · neutron absorption · transmutation · long-lived
depleted uranium
Processed nuclear byproduct, very dense
- thoriumActinide, atomic number ninety
- uranium-238Predominant uranium isotope
- actinideHeavy radioactive metal series
heavy metal · dense · metallic · armor plating · counterweight · ballast · penetrator · cladding · industrial applications
reactor
Controlled fission apparatus
- criticalityState of utmost importance
- chain reactionSelf-sustaining causal sequence
- fertileAble to reproduce abundantly
enrichment · nuclear fuel cycle · spent fuel · transmutation · cross-section · nuclear physics · radioactive decay
nonfissionablefissionable
Able to split atomically
fissile · weapons-grade · enriched · fertile · splittable