Deformation type during the ball milling process: A comparative study of the microstructures formed by ball milling, uniaxial compression, and rolling

The plastic deformation type of metal during ball-milling treatment has not yet been unveiled due to the difficulty in direct observation, and it is also difficult to clarify the deformation behavior even by numerical simulations. A comparative study of the effects of lubrication on the microstructure induced by ball-milling, compression, and rolling was con. Ducted to reveal the deformation type. The deformed flake particle showed a uniform microstructure for the ball-milling treatment with a lubricant. By contrast, the closer the particle surface, the finer the crystal grains were for the treatment without a lubricant. These microstructural features on the ball-milled iron particles were observed in rolled iron sheets, and the effects of the lubricant on the microstructure induced by compression were the opposite. Therefore, we conclude that the type of ball-milling-induced deformation is close to rolling, considering the similarity of the effect of the lubricant on the microstructures.