Improving Composite Tensile Properties during Resin Infusion Based on a Computer Vision Flow-Control Approach

Area of Science:

• Materials Science
• Mechanical Engineering
• Manufacturing Processes

Background:

• Liquid composite manufacturing is crucial for the transport industry, with decades of optimization focused on defect reduction for enhanced reliability and performance.
• Process parameters critically influence composite mechanical behavior, with flow front velocity and void content being particularly significant factors.

Purpose of the Study:

• To evaluate and control the optimal flow front velocity in liquid composite manufacturing using a computer vision system.
• To improve mechanical tensile properties and reduce void content in composite laminates by maintaining a constant, optimal flow front velocity.

Main Methods:

• Implementation of a computer vision system to monitor and control the flow front velocity during resin film infusion (RFI).
• Utilizing a feedback flow-controller to maintain the optimal flow front velocity, thereby minimizing air entrapment.
• Testing of composite laminates with varying fiber orientations (0° and 90°) to assess mechanical properties.

Main Results:

• Enhanced mechanical tensile properties were achieved by maintaining a constant optimal flow front velocity.
• Tensile strength increased by up to 18% at 0° and 3.3% at 90° fiber orientation.
• Tensile modulus improved by up to 18.4% at 0° and 8.7% at 90° fiber orientation, with reduced void content.

Conclusions:

• A novel methodology using computer vision for flow front velocity control enhances the robustness and quality of resin film infusion (RFI) processes.
• The developed system effectively reduces air traps and improves key mechanical properties of composite materials.
• This approach offers a pathway to more reliable and higher-performing composite structures.