Effect of vacuum venting process on replication of nano/micro-features in microinjection molding: quantitative and qualitative analysis

摘要

Vacuum venting is one of the methods proposed to improve feature replication in microparts that are fabricated using micro injection molding (MIM). A qualitative and quantitative study has been carried out to investigate the effect of vacuum venting on nano/micro feature replication in MIM. Anodized aluminium oxide containing nanofeatures and bulk metallic glass tool mold containing micro features were used as mold inserts. The effect of vacuum pressure at constant vacuum time, and vacuum time at constant vacuum pressure on the replication of these features is investigated. It is found that the vacuum venting application has qualitatively enhanced the nano-scale feature definition as well as increased the area of feature replication. In the quantitative study, higher aspect ratio features can be replicated more effectively using vacuum venting. Increasing both vacuum pressure and vacuum time are found to improve the depth replication, with the vacuum pressure having more influence.