B₄C (90% B-10 enriched)
B₄C
AbsorbersDensity: 2.393 g/cm³
Atom density: 0.137349 atoms/b·cm
Boron carbide enriched to 90 at% B-10, for control rods and shields that need maximum absorption per unit volume.
Where these numbers come from
B₄C stoichiometry with boron enriched to 90 at% B-10. Density scaled from the compendium's natural boron carbide (2.52 g/cm³) by the molar-mass ratio, since enrichment changes the mass of the lattice and not its spacing.
Material compositions from PNNL-15870 Rev. 2 (April 2021), R.S. Detwiler, R.J. McConn Jr., T.F. Grimes, S.A. Upton, and E.J. Engel, Compendium of Material Composition Data for Radiation Transport Modeling, Pacific Northwest National Laboratory. Full report (DOI 10.2172/1782721)
Composition
| Nuclide (ZAID) | Weight fraction | Atom fraction | Atom density (atoms/b·cm) |
|---|---|---|---|
| B-10 (5010) | 6.8711e-1 | 7.2000e-1 | 9.8892e-2 |
| B-11 (5011) | 8.3943e-2 | 8.0000e-2 | 1.0988e-2 |
| C-12 (6012) | 2.2629e-1 | 1.9786e-1 | 2.7176e-2 |
| C-13 (6013) | 2.6522e-3 | 2.1400e-3 | 2.9393e-4 |
This is the material as formulated. The cards below carry weight fractions, written negative, which is what MCNP and Serpent read as a mass basis.
Generated material cards
c B4C (90% B-10 enriched)
c ReactorMC NRDP derived material - reactormc.net/nrdp/material/b4c-enriched;
c rho = 2.393 g/cm3 (use -2.393 on the cell card)
m33 5010.80c -0.687111 $ B10
5011.80c -0.083943 $ B11
6000.80c -0.228946 $ CMCNP and Serpent cards use .80c (ENDF/B-VII.1 at 293.6 K) — renumber m1 and change the suffix to match your deck. SCONE compositions are atom densities in atoms/barn-cm with the .03 suffix matching temp 300. See the library reference before changing a suffix: the mapping is not portable between vendors.
Notes
Enrichment raises the B-10 atom density by about 4.5× over natural boron. It also lowers the mass density to ~2.39 g/cm³ — the old entry kept 2.52, the natural value, and so overstated the material by 5%.