Methods of forming structures and fissile fuel materials by additive manufacturing and related structures

A method of additively manufacturing a structure, the method comprising:

• disposing a first layer of a powder onto a surface of a substrate;
• compacting the first layer of the powder on the surface of the substrate;
• exposing the first layer of the powder to defocused laser radiation to form a first layer of a structure comprising inter-granular bonds between particles of the powder;
• disposing a second layer of another powder on the first layer of the structure;
• and
• exposing the second layer of the another powder to defocused laser radiation to form a second layer of the structure.

A method of forming a structure, the method comprising:

• providing a substrate within an enclosure;
• disposing a powder on the substrate;
• exposing the powder on the substrate to defocused laser radiation to form a first layer of a structure;
• disposing additional powder over the first layer;
• and
• exposing the additional powder over the first layer to defocused laser radiation.

A structure including a fissile fuel material, comprising:

• at least a first layer comprising a fuel material dispersed in a graphite matrix material, wherein particles of the fuel material are directly bonded to adjacent particles of the graphite matrix material,
• the fissile fuel material exhibiting a graphite to total carbon ratio equal to about 1.0:1.0;
• and
• at least a second layer of another material bonded to the first layer.