In powder filling into a die cavity, higher and uniform density with little weight variation is generally required. In contrast to the conventional feeding system with guiding rail, the 2-axis electric drive CNC feeder developed can move the feedshoe flexibly on die plate, and according to cavity shape the feeding conditions such as feeding path, position and speed can be easily changed on NC program. In this study, the effects of average and forward/backward feeding speed on filling density and horizontal distribution have been investigated.
Among 4 different types, the filling density into die cavities of deep ring (??70×??60×t30) and thin plate (??70×t2) exhibited greater decrease with an increase in feeding speed. Investigations of local density distribution revealed that the decrease with higher feeding speed for the deep ring was mainly caused by insufficient fill in whole area, and for the thin plate by the loss of powder at the end of cavity in feeding direction which was raked off with retracting motion of feedshoe.