A study on gas penetration and fingering behavior in injection molding of polymer and powder metal feedstock.

摘要

The effect of processing variables on the level of gas penetration in parts fabricated by gas-assisted injection molding from two different materials was compared. The materials used were polypropylene and stainless steel powder metal/thermoplastic feedstock. Software simulation and physical experiments were conducted. Taguchi analysis was used to reduce the number of experiment trials and to find the optimum processing conditions. Four different variables were changed using nine different combinations. The processing variables are the pressure, the delay time before gas is injected, the temperature of the material injected, and the amount of the material injected. The results showed that the most critical variable in the experiment is shot size followed by gas pressure, delay time and material.