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Bulk metallic glasses (BMGs) display excellent strength, high hardness, exceptional wear resistance and corrosion resistance owing to its amorphous structure. However, the manufacturing of large-sized and complex shaped BMG parts faces significant difficulties, which seriously hinders their applications. Laser powder bed fusion (LPBF) is a typical additive manufacturing (AM) technique with a cooling rate of up to 108 K/s, which not only allows for the formation of amorphous structures but also solves the forming problem of complex-shaped BMG parts. In recent years, a large amount of work has been carried out on the LPBF processing of BMGs. This review mainly summarizes the latest progress in the field of LPBF additively manufactured BMGs focusing on their mechanical properties. We first briefly review the BMG alloy systems that have been additively manufactured using LPBF, then the mechanical properties of LPBF-fabricated BMGs including the micro- and nano-hardness, micropillar compressive performance, and macro-compressive and tensile performance are clarified. Next, the relationship between the mechanical properties and microstructure of BMGs produced via LPBF are analyzed. Finally, the measures for improving the mechanical properties of LPBF-fabricated BMGs are discussed. This review can provide readers with an essential comprehension of the structural and mechanical properties of LPBF-manufactured BMGs. [ABSTRACT FROM AUTHOR]

Laser powder bed fusion (LPBF) technology presents significant potential for the production of metallic glass (MG) coatings. This work investigated the influence of laser power on the structure and wear performance of a CuZr-based metallic glass coating with composition of Cu 45 Zr 45 Al 6 Ti 4 on Ti substrate. It was observed that the melt pool, which serves as the fundamental building block for constructing MG coatings in LPBF, undergoes a transition from conduction mode to keyhole mode, and subsequently to extended mode with increasing laser power. The MG coatings prepared using low power laser (140 W) and medium power laser (240 W) both exhibited a nearly fully amorphous state. However, at a laser power of 360 W, noticeable crystallization occurred in the coating, as evidenced by SEM observation. The wear rate of Cu 45 Zr 45 Al 6 Ti 4 MG coating was measured to be 4.67 × 10−6 mm3·N−1·m−1, which is significantly lower than that of the Ti substrate (6.38 × 10−4 mm3·N−1·m−1). This study reveals the relationship between the laser power and morphology of the melt pool, as well as the structure and wear performance of the LPBF-fabricated MG coatings, offering guidance for optimizing the laser additive manufacturing process of wear-resistant MG coatings. [Display omitted] • Melt pool in MG changes from conductive to keyhole, then to extended mode with increasing laser power. • A strategy to optimize LPBF parameters for MG coatings based on melt pool characteristics is proposed. • Keyhole melt pool can promote formation of amorphous structure with low porosities in MG coatings. • Cu 45 Zr 45 Al 6 Ti 4 MG coating shows 136 times higher wear resistance than the Ti substrate. [ABSTRACT FROM AUTHOR]