High-velocity ice bullets could someday be used to weld everything from car parts to industrial components. The trick could provide an alternative to heat, electric arcs or bulky hydraulics for precision spot welding.
Researchers at Ohio State University, US, freeze water into the shape of a sharp bullet and use a gas gun to fire them at a metal sheet. These high-energy projectiles briefly plasticise the metal, causing it to deform and bond with whatever it is touching. Carefully aiming bullets at near point blank range can very quickly be used to create precision welds.
If a metal sheet is backed with a carefully-shaped material, a barrage of ice bullets can also be used to shape the metal. And the only waste product is water when the ice melts.
Read the full ice bullet welding patent application
.Barry Fox, New Scientist consultant.