Characterization, preparation, and reuse of metallic powders for laser powder bed fusion: a review

Abstract

Laser powder bed fusion (L-PBF) has attracted significant attention since its inception, providing unprecedented advantages to fabricate metallic components with complex geometry. The quality and performance of as-printed alloys is an intricate function consisting of numerous factors linking the feedstock powders, manufacturing, and post-treatment. As the starting materials, powders play a critical role in influencing the printing consistency, total fabrication cost, and mechanical properties. In consideration of its importance for L-PBF, the present review aims to review the recent progress on metallic powders for L-PBF focusing on powder characterization, powder fabrication, and powder reuse. The methods of powder characterization and fabrication were presented in the beginning by analyzing the principles and corresponding advantages and limitations. Subsequently, the effect of powder reuse on the powder characteristics and mechanical performance of L-PBF parts is analyzed focusing on steels, nickel-based superalloys, Ti and Ti alloys, and Al alloys. The evolution trend of powders and as-printed parts varies for different alloy systems based on the existing studies, which makes the proposal of a unified reuse protocol infeasible. Finally, perspectives are presented to cater to the increasing applications of AM technologies for future investigations. The present state-of-the-art work can pave the way for the broad industrial applications of L-PBF by enhancing printing consistency and reducing the total cost from the perspective of powders.

Investigation of an Increased Particle Size Distribution of Ti-6Al-4V Powders Used for Laser-Based Powder Bed Fusion of Metals

“…As high relative densities and industry-standard mechanical properties were achieved for all the powders, it is more likely that the process parameters affected irregularities in the powder bed. However, the complexity of the causal relationship between powder, process, and part qualities, as demonstrated by Sun et al, requires further investigations [ 1 ]. The correlation of particle shape with improved flowability and tensile properties needs to be relativized, due to the similarity of the particle shapes investigated.…”

“…Despite its remarkable advantages, the widespread adoption of PBF-LB/M still faces challenges, particularly concerning costs. The cost of metal powders as a feedstock material remains a critical barrier to the broader application of PBF-LB/M [ 1 ]. To address this issue, exploring strategies to reduce manufacturing costs without compromising quality has become imperative [ 2 , 3 ].…”

Correlative spatter and vapour depression dynamics during laser powder bed fusion of an Al-Fe-Zr alloy

“…, where L is the track length, and m and v m are the mass and velocity of individual spatter, respectively. The mass of spatter is given as m = 4 3 π r 3 ρ, where r is the equivalent radius of spatter, ρ is the density of spatter which is taken as 2710 and 2385 kg m −3 for solid and liquid aluminium, respectively [46].…”

“…Laser powder bed fusion (LPBF) is a prominent additive manufacturing (AM) technology that manufactures near-net shape metallic components with exceptional design freedom, minimal lead time, and no tooling cost, on a layer-by-layer basis [1][2][3][4]. However, the adoption of LPBF for safety critical applications is hindered by the challenge of achieving defectlean, high-density metallic components that meet critical quality standards [5,6].…”

Reuse of Smoulder in Laser Powder-Bed Fusion of AlSi10Mg—Powder Characterization and Sample Analysis

“…Moghimian et al [32] and Smolina et al [33] reached similar conclusions of comparable tensile properties of samples from virgin and reused powder of AlSi10Mg and AlSi7Mg0.6. If L-PBF process parameters and powder quality control or powder preparation are set properly, reused powder can serve as a feedstock material to high-quality parts [33,34].…”