Abstract:
Metal powder products with the different shapes have the different pressing behaviors under the high speed pressing, easily leading to the change in relative density and density uniformity. Most of powder products contain the taper angle structure, and the densification degree of metal powders will change with the taper angle in the process of pressing. The relative density of the conical parts at different angles under impact loading was investigated by discrete element software PFC3D in this paper. It is found that, the relative density shows the fluctuating variation with the multiple peaks and troughs when the taper angle is between 30° and 60°, but the overall trend is upward, and the relative density reaches the maximum value in the trough change with the taper angle between 45° and 60°. When the taper angle is greater than 60°, the relative density decreases. With the increase of the friction coefficient, the relative density decreases, and the effect on the small taper angle parts increases. The comprehensive analysis shows that, the taper angles at 45° and 60° are always near the peak relative density, and the uniformity coefficient is smaller than other angles. 45° is the excellent angle for the taper angle parts, showing the higher relative density and uniformity. The experimental results verify the accuracy of the simulation, providing the theoretical basis for the optimal pressing of conical parts.