The Effect of Process Parameters on the Ejection of Powder Compacts

摘要

The paper describes the use of an instrumented die and rigid die to explore ejection mechanisms in powder compaction. Both equipments confirm that ejection stress is about 10% of the average axial stress at the end of compaction. Results from the instrumented die suggest that the friction coefficient during compression and ejection are very similar. The rigid die experiments confirm the impact of lubricant addition on ejection and that lubricant type has a secondary impact. Lubricant addition seems to have little effect on ejection at low compaction pressures since the powder is not subject to significant deformation and the admixed lubricant is not extruded onto the surface between the die and compact.