Microwave welding of polymers

¹ Heat Transfer and Fluid Flow Laboratory, Faculty of Mechanical Engineering, Brno University of Technology, Technicka 2896/2, 616 69 Brno, Czech Republic
² Department of Radio Electronics, Faculty of Electrical Engineering and Communication, Technicka 3058/10, 616 00 Brno, Czech Republic

^* Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.

Published online: 12 March 2026

Abstract

The growing demand for fast, efficient and environmentally friendly polymer joining techniques has intensified research on microwave welding methods. However, there remains a knowledge gap regarding the influence of susceptor composition, welded material properties, field strength and welding duration on joint strength, which limits the optimization of this technology for industrial applications. In this study, we investigate the effects of several susceptor types – polypropylene (PP) supplemented with 75% graphite admixtures, polylactic acid (PLA) with 20% of carbon, polyethylene terephthalate glycol (PET-G) with tungsten, PLA with 45% of iron and PET-G with magnetite, and such thermoplastics as PET-G, PLA and PP on the mechanical strength of welded joints. The microwave welding process is conducted using dielectric heating at the frequency of 2.45 GHz. The results demonstrate that the interaction effects between susceptor type and welded material are found to be significant, highlighting the necessity of multivariate optimization rather than single-factor tuning. This work provides practical insights into the development of reliable, energy-efficient, and scalable polymer joining processes. The presented findings contribute to advancing microwave welding techniques and can serve as a foundation for further industrial applications.