Advanced Engineering Materials, vol.26, no.14, 2024 (SCI-Expanded)
Laser-powder bed fusion (L-PBF) is extensively adopted in the aerospace and automobile industries for producing metallic components. The L-PBF process involves rapid melting and solidification of metallic powders using a laser source to produce dense parts. Most industrial L-PBF systems use a fiber-based laser source that emits a Gaussian beam distribution. However, the conventional Gaussian beam used in L-PBF processes presents inherent limitations that can impact the quality and properties of the final products. This review aims to provide a theoretical background of laser beam shaping techniques and explores the application of alternative beam shapes in L-PBF. It investigates how different beam profiles affect the melt pool geometry, process stability, productivity, mechanical properties, microstructure, and surface roughness of fabricated parts. Additionally, it discusses different types of beam shaping techniques and elements utilized to generate distinct beam shapes. Furthermore, different constraints and limitations that hinder the full exploitation of beam shaping are critically discussed. By analyzing the impact of beam shaping in L-PBF, this review provides insight into optimizing the additive manufacturing process, enhancing part quality, and improving processing performance. It will also help readers to overview the research gaps, challenges, and promising future directions in laser beam shaping applications in L-PBF.