3D Printing of Metallic Microstructured Mould Using Selective Laser Melting for Injection Moulding of Plastic...

Area of Science:

• Materials Science and Engineering
• Microfluidics
• Additive Manufacturing

Background:

• Microfluidic devices are crucial for lab-on-a-chip applications, requiring precise microstructures.
• Conventional micro-fabrication methods for microfluidic molds are often slow, expensive, and lack flexibility.
• Rapid prototyping and early-stage scale-up of microfluidic devices necessitate faster and more adaptable mold fabrication techniques.

Purpose of the Study:

• To investigate the feasibility of using selective laser melting (SLM) 3D printing for fabricating microfluidic chip molds.
• To characterize the dimensional accuracy, surface morphology, and bonding strength of SLM-printed micro metallic patterns on a substrate.
• To evaluate the performance of microfluidic chips molded using SLM-fabricated tools for environmental monitoring.

Main Methods:

• Selective laser melting (SLM) 3D printing was employed to create micro metallic patterns on a substrate, forming a microstructured mold.
• Characterization techniques were used to assess dimensional accuracy, surface morphology, bonding strength, and microstructural features of the printed patterns.
• The fabricated mold was directly used for injection molding of cyclic olefin copolymer (COC) microfluidic chips.
• The molded microfluidic chips were utilized for monitoring nitrite concentrations in environmental water samples.

Main Results:

• A microfluidic mold with micro metallic patterns was successfully fabricated using SLM 3D printing.
• Characterization confirmed the successful printing of micro features with assessed dimensional accuracy and surface morphology.
• Injection molding using the SLM-fabricated mold yielded functional cyclic olefin copolymer (COC) microfluidic chips.
• The microfluidic chips demonstrated successful application in monitoring nitrite concentrations in environmental water.

Conclusions:

• Selective laser melting (SLM) is a viable technique for the rapid fabrication of mold tools for microfluidic devices via injection molding or hot embossing.
• The SLM process offers advantages in speed, flexibility, and cost-effectiveness compared to conventional micro-machining methods.
• Further process optimization and potential hybrid approaches combining SLM with traditional machining are recommended to enhance accuracy and surface finish for advanced microfluidic applications.