Residual Stress in Powder Metallurgy Green Compact

Residual stress in green compact is an important factor to influence the quality of the compact and corresponding powder metallurgy product. To understand the residual stress, a finite element model is set up to simulate the single and double action pressing, unloading and ejecting of powder compacting process. Results show that compaction type has significant influence on the rule of residual stress state and the double action pressing is more helpful to reduce the risk of cracking than the single action pressing. Also better lubricant condition is beneficial to improve residual stress in the green compact.