Abstract: Some flow stress models was used to simulate the compaction of a cylindrical specimen. A new flow stress model was presented by analyzing and summarizing the powder compact experiment with different initial densities. Compared with other models, the new model fits better with the experiments. The compaction process of a synchronizer hub was simulated with new model and the synchronizer hub shape was improved by the simulation results. The density distribution was measured and compared with the simulation results of splitting the samples into pieces. The comparison shows that the model could be used to simulate the powder compact process in an efficient and accurate manner. And the results indicate that the density distribution is homogenous after optimization.

Key words: powder compaction; design distribution; numerical simulation