Abstract
One of the most important subjects in the P/M manufacturing is productivity of compacts. There are two processes that are controlling productivity in P/M manufacturing. (1) Discharging of powders from the hopper. (2) Filling of powder into the die cavity.
To evaluate the discharging characteristics of powders, the simplified discharging equipment was designed to measure the critical discharging diameter of iron based pre-mixed powder. The critical discharging diameter showed good relation to flow patterns of powders in the hopper.
In the die filling process, the air release from the die cavity was found to be important phenomena. “Agitating-shoe” which can accelerate the air release from the die cavity was able to increase the filling rate and decrease the weight variation of compacts compared to a conventional feed shoe.
