Experimental and numerical analysis of laser-welded GFRP–PBT joints for aerospace components

Abstract

This study investigates laser transmission welding of 30% glass fiber-reinforced polybutylene terephthalate (PBT-GF30). Injection-molded plates were used as base material, from which specimens were prepared, welded, and experimentally tested. The influence of key process parameters, including laser power, beam size, and scanning speed, on weld quality was systematically evaluated through an iterative optimization approach. An optimized parameter set (400 W laser power, reduced beam size, and increased scanning speed) enabled stable and repeatable weld formation with minimal thermal degradation. Experimental results were further supported by finite element analysis, showing good agreement between numerical and experimental data. The findings confirm the feasibility of laser welding for PBT-GF30 and its potential for aerospace applications requiring precision, weight reduction, and structural reliability.