CONFORM process: surface separation, curling and process characteristics to the wheel diameter

Even though CONFORM process can extrude ultra-long seamless products of various section shapes with high extrusion ratio, without pre-heating and post-mechanical treatment, it suffers two inherent process defects, the surface separation and the curling phenomenon. These process defects are caused basically by the circular material flow driving by the rotating wheel. Therefore, the parametric investigation on the process defects with respect to the wheel diameter is of importance, although the material flow is also characterized by other several process parameters. In this paper, we numerically examine the effects of the wheel diameter on the surface separation and curling phenomenon as well as other significant process characteristics, through the two-dimensional finite element analysis of CONFORM process for solid section aluminum products.