A solid metallic cuboid of dimensions 9 m × 8 m × 2 m is melted and recast into solid cubes of edge 2 m.

The volume of solid metallic cuboid is $9 \times 8 \times 2=144 \mathrm{~m}^{3}$.

This cuboid has been recasted into solid cubes of edge $2 \mathrm{~m}$ whose volume is given by $2^{3}=8 \mathrm{~m}^{3}$.

Therefore, the total number of cubes so formed $=\frac{\text { the volume of solid metallic cuboid }}{\text { the volume of solid cubes }}=\frac{144}{8}=18$.