A review of laser additive manufacturing of high-entropy alloys: technologies, properties, and research perspectives

Abstract This paper systematically reviews the characteristics of high-entropy alloys (HEAs), the challenges in their fabrication, and the applications of additive manufacturing (AM) technologies in HEA production. It first introduces the properties, microstructures, and limitations of traditional fabrication methods. Then, it provides a detailed evaluation of three representative AM techniques—Selective Laser Melting (SLM), Electron Beam Melting (EBM), and Laser Metal Deposition (LMD)—analyzing their respective advantages and disadvantages regarding precision, performance, and suitability for different applications. To highlight the significant microstructural and performance differences induced by AM processes, the classic CoCrFeMnNi (Cantor) alloy is selected as a benchmark. This work systematically compares its processing-induced characteristics across SLM, EBM, and LMD, offering detailed insights not comprehensively covered in previous studies. The study finds that laser-based processes like SLM and LMD, benefiting from rapid solidification and precise thermal control, demonstrate unique advantages in achieving refined microstructures and enhanced mechanical properties. Meanwhile, EBM, relying on vacuum electron beam melting, provides benefits in reducing oxidation, improving compositional uniformity, and fabricating large components. Each technique shows distinct strengths and challenges related to processing compatibility and difficulty. The integration of external physical fields further enhances microstructural regulation and residual stress relief. Finally, the paper proposes new directions for gradient structure design and intelligent process optimization, providing valuable guidance for future research and practical applications of AM technologies in the fabrication of high-performance HEAs.