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Updated: Oct 25, 2025
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Ultrasonic Welding of Thermoplastic Composite Coupons for Mechanical Characterization of Welded Joints through Single Lap Shear Testing
Published on: February 11, 2016
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Multi-Objective Optimization of Resistance Welding Process of GF/PP Composites
Guowei Zhang1, Ting Lin2, Ling Luo1
1School of Materials Science and Engineering, Beihang University, Beijing 100191, China.
Polymers
|August 10, 2021
Summary
This study optimizes resistance welding for glass fiber-reinforced polypropylene thermoplastic composites. Welding current significantly impacts lap shear strength, with optimal parameters yielding strong, reliable joints for diverse applications.
Area of Science:
- Materials Science
- Mechanical Engineering
- Composite Materials
Background:
- Thermoplastic composites (TPCs) offer advantages like lightweight and recyclability for aerospace and automotive sectors.
- Fusion connections, especially resistance welding, are superior to mechanical or adhesive joints for TPCs.
- Optimizing resistance welding is key to unlocking the full potential of TPCs in structural applications.
Purpose of the Study:
- To investigate and optimize the process parameters for resistance welding of glass fiber-reinforced polypropylene (GF/PP) TPCs.
- To determine the influence of welding current, time, and pressure on the lap shear strength (LSS) of GF/PP TPCs.
- To establish optimal welding conditions for robust and reliable TPC component connections.
Main Methods:
- Fabrication of GF/PP laminates and evaluation of their mechanical properties.
- Development and utilization of custom resistance welding equipment for GF/PP TPCs.
- Application of the Taguchi method with signal-to-noise (S/N) ratio and ANOVA to analyze tensile shear test data.
Main Results:
- Welding current was identified as the most critical factor influencing the resistance welding quality of GF/PP TPCs.
- Optimal process parameters were determined as 12.5 A current, 2.5 MPa pressure, and 540 s time.
- Experimental lap shear strength (LSS) reached 12.186 MPa under optimized conditions, closely matching predictions.
Conclusions:
- Resistance welding is a viable and effective joining method for GF/PP TPCs.
- Optimized process parameters ensure high lap shear strength and reliable performance of TPC joints.
- This research provides a foundation for the industrial application of optimized resistance welding in TPC manufacturing.
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