Advances in computational modeling for laser powder bed fusion additive manufacturing: A comprehensive review of finite element techniques and strategies

Abstract

The laser powder bed fusion process, a prominent additive manufacturing method, involves intricate thermal dynamics and stress distribution. Despite the mature knowledge base in laser processing, laser powder bed fusion simulations are computationally intensive due to the intricate interactions of fluid dynamics, evaporation, and chemical reactions. Success in laser powder bed fusion builds remains uncertain until attempted, with common failures such as warpage, distortion, and support-related issues. The high cost of physical iteration for optimization emphasizes the importance of modeling-aided fabrication to estimate and mitigate build failures. Numerous finite element method-based studies exist, but comprehensive documentation on numerical techniques and strategies for laser powder bed fusion modeling is lacking, hindering accessibility for researchers. This review addresses this gap by consolidating existing knowledge on thermomechanical modeling in laser powder bed fusion. It aims to guide novices, practitioners, and designers, offering insights into current practices, challenges, and prospects. The review encompasses the entire laser powder bed fusion workflow, emphasizing the critical role of finite element modeling in achieving first-time-right parts with desired properties. Rationale and methodology are established in the initial sections, providing a snapshot of current research directions. The foundational scientific understanding, covered in subsequent parts, includes thermomechanical analysis, orientation modeling, discretization strategies, and crucial process considerations. Consequently, for the completeness of the subject matter, several practical applications are exhibited through in-house simulations and examples from the literature. Building on macroscopic insights, the review further delves into microstructural modeling, elucidating governing equations, and showcasing simulations for microstructure evolution. To propel research forward, future possibilities, such as recoater interference, sintering simulations, and multi-material scenarios, are explored. The review concludes by offering perspectives on the outlook of finite element modeling in the laser powder bed fusion process. This comprehensive resource facilitates a deeper understanding for researchers in laser powder bed fusion and guides the end-users for practical implementation.