Explainer | Ukraine war: what are depleted uranium weapons – and the risks?
- Here’s a look at the uranium-based ammunition the UK will send to Ukraine
- The armour-piercing rounds are a highly effective but controversial weapon
What are these munitions?
Depleted uranium is a dense by-product left over when uranium is enriched for use in nuclear reactors or nuclear weapons.
The depleted uranium is still radioactive but has a much lower level of the isotopes U-235 and U-234 – way less than the levels in natural uranium ore – reducing its radioactivity.
It is used in weapons because it is so dense, it self-ignites at high temperatures and pressures, and because it becomes sharper – “adiabatic shearing” – as it penetrates armour plating, according to the International Atomic Energy Agency.
“As a DU penetrator strikes a target, its surface temperature increases dramatically,” according to the Oak Ridge Associated Universities (ORAU) Museum of Radiation and Radioactivity in Tennessee, United States.
“This causes localised softening in what are known as ‘adiabatic shear bands’ and a sloughing off of portions of the projectile’s surface. This keeps the tip sharp and prevents the mushrooming effect that occurs with tungsten.”
“When the DU penetrates the target vehicle, the larger fragments tend to chew up whatever is inside while the pyrophoricity of the uranium increases the likelihood that the vehicle’s fuel and/or ammunition will explode.”