Using FEA in assessing backward extrusion of multiple micro-pins

FE analyses of backward extrusion of multiple micro-pins have been conducted to examine the effects of pin geometry, layout and spacing. The effect of friction on material flow and accuracy of pin geometry has been investigated. FE analysis was performed for a commercial grade Al1050 as well as its ultrafine grained version produced by severe plastic deformation allowing a comparison to be made. Pin layout plays a large role in achieving uniformity of pin height. Material starvation resulted in the central pins being shorter than the surrounding pins. Simulations without the centre pin were conducted, which resulted in increased pin height uniformity. Simulations with friction resulted in a greater uniformity of pin height but required a greater load. Using stronger ultrafine grained material increased the load and reduced the pin height uniformity.