Micro injection molding is a very accurate injection molding technique that is employed for the construction of very small parts. More specifically, parts that weigh less than one gram, are feasible to be constructed.

The process is characterized by the injection of a very small amount of resin into a mold under high pressure via syringe-sized injection machine. During this step, precised control of the injection pressure, flow rate and temperature is required. Afterwards, the part starts to solidify as it cools down.

The following figure indicates a typical setup of the Micro Injection Molding.

Fig. 1Micro Injection Molding setup

Mold design

Since the parts produced by Micro Injection Molding are characterized by high accuracy, the construction of the mold should also be precised. Thus, for the construction of the mold, precised tooling such CNC and EDM (Electrical Discharge Machining) should be employed. The manner in which the part cools down within the mold and the removal of the excess material, is of great importance (AcoMold, 2024).

Appropriate materials for Micro Injection Molding

• Thermoplastic Elastomers (TPEs)
• Polyoxymethylene (POM)
• Polycarbonate (PC)
• Polyether Ether Keton (PEEK)
• Liquid Silicon Rubber (LSR)

Bibliography

AcoMold. (2024, 4 2). Retrieved from The Complete Guide to Micro Injection Molding: Processes, Benefits, and Applications: https://www.acomold.com/micro-injection-molding.html