Efficient and Precise Micro-Injection Molding of Micro-Structured Polymer Parts Using Micro-Machined Mold Core by...

Area of Science:

• Materials Science and Engineering
• Manufacturing Technology
• Polymer Processing

Background:

• Micro-structured polymer parts are crucial for various advanced applications.
• Traditional fabrication methods can be costly and time-consuming for mass production.
• Efficient and accurate methods are needed for low-cost manufacturing of micro-structured polymers.

Purpose of the Study:

• To develop a cost-effective and high-precision method for fabricating micro-structured polymer parts.
• To investigate the influence of micro-injection molding parameters on replication accuracy and surface quality.
• To optimize the micro-injection molding process for mass production.

Main Methods:

• Micro-structured mold cores were fabricated using wire electrical discharge machining (WEDM).
• Micro-injection molding was employed to replicate micro-structures onto polymer workpieces.
• Systematic investigation and analysis of micro-injection molding process parameters (temperature, velocity, pressure, time).

Main Results:

• Achieved a minimum machining error of 0.394% for the micro-structured mold core.
• Attained a maximum replication rate of 99.12% for micro-structured polymer workpieces.
• Determined optimal parameters: jet temperature (195°C), melt temperature (210°C), injection velocity (40 mm/min), holding pressure (7 MPa), and holding time (5 s).
• Minimized surface roughness (Ra) to 0.805 µm at groove bottoms and 0.972 µm at groove tops.

Conclusions:

• The combined WEDM and micro-injection molding process enables rapid and precise fabrication of micro-structured polymers.
• The developed method is suitable for low-cost mass production of micro-structured polymer products.
• Optimization of process parameters is key to achieving high replication rates and excellent surface quality.