Deformation-induced alloying of Cu sheet with Al using ball collisions

•Balls were coated with Al by mechanical alloying.•Cu sheet was treated by balls coated with Al.•Al was introduced into the Cu sheet.•Deformation induced intermixing of elements.•Hardness increased more than four times.

Cu sheet was alloyed with Al using ball collisions at room temperature and ambient atmosphere. Al was introduced into the Cu sheet as contamination from the grinding media. The idea here was first to coat the balls with Al by mechanical alloying and treated the surface of the Cu sheet using ball collisions. The Al debris from the grinding media was first to adhere to the Cu sheet under the ball collisions and then the deformation-induced diffusion and intermixing of the elements resulted in the formation of the Cu(Al) solid solution. The size of nanocrystalline grains after treatment ranged between 10 nm and 50 nm and an average of about 20 nm. The hardness of the Cu sheet after the treatment was increased more than four times.