容器の冷間押出し加工における偏肉 : 第3報, ブランクの端面の傾斜および摩擦の不均衡による偏肉

抄録

Deviation of punch load center from punch center, lateral force exerted on the punch head and eccentricity between punch and die are measured through the process. In extruding a blank of slant end, punch is remarkably bent toward the low end side by the lateral force in the initial stage of extrusion. The punch tends to recover elastically in the subsequent stage, and the eccentricity between punch and die decreases as the process proceeds. The recovery is, however, retarded more or less by the resistance of the deforming metal around the punch. In extruding a blank of which lubricant film is removed from a half of the end surface, both the deviation of punch load center from the punch center and the lateral force induced by the non-axisymmetric flow bend the punch toward the dry end side. The eccentricity between punch and die increases with increase in the punch penetration.