Influence of surface condition on the degradation behaviour and biocompatibility of additively manufactured WE43

Biodegradable magnesium alloy WE43 porous scaffolds fabricated by laser powder bed fusion for orthopedic applications: Process optimization, in vitro and in vivo investigation

“…As shown in Figs. 6 and 7 , the microstructure of WE43 porous scaffolds were composed of α-Mg, Y 2 O 3 and MgRE precipitates, consistent with the previous literatures [ [43] , [44] , [45] , [46] , [47] , [48] , [49] , [50] , [51] , [52] ]. This work firstly reported the influence of strut size on the microstructure of porous scaffolds.…”

“…The elemental ratios indicates that they are composed of Mg 14 (Nd,Gd) 2 Y, which is a typical type of metastable β phases precipitated in the rapid cooling [ 58 ]. Metastable β-Mg 3 Nd, β-Mg 3 Gd and β-Mg 14 Nd 2 Y were widely reported in WE43 casting and L-PBF process [ 43 , 44 , 46 , [48] , [49] , [50] , [51] , [52] ]. Gd replaces Nd in β-Mg 14 Nd 2 Y because of their similar atomic radius.…”

“…Despite the difficulties, L-PBF of Mg alloys has made great progress in the latest decade [ [32] , [33] , [34] , [35] , [36] , [37] , [38] , [39] , [40] , [41] , [42] , [43] , [44] , [45] , [46] , [47] , [48] , [49] , [50] , [51] , [52] , [53] , [54] ]. Ng et al firstly attempted L-PBF of pure Mg in 2010 [ 32 ].…”

“…Hot cracking was seldom observed during the L-PBF of WE43 alloy owing to the relatively narrow solidification temperature, however, massive precipitation phases including MgRE compounds and RE oxides were found in WE43 L-PBF parts. Although the strength of WE43 bulks fabricated by L-PBF was higher than casted counterparts and comparable to extruded counterparts, the in vitro corrosion rate was higher than those of casted and extruded counterparts [ [43] , [44] , [45] , [46] , [47] , [48] , [49] ].…”

“…Porous scaffolds consist of small-sized struts and interconnected pores enclosed by the struts. In contrast to the widely reported consistent results on the WE43 bulk samples [ [43] , [44] , [45] , [46] , [47] , [48] , [49] ], limited works investigated WE43 porous scaffolds fabricated by L-PBF [ [50] , [51] , [52] , [53] ]. The performance of porous scaffolds depends on the structural design and the formation quality, and is sensitive to formation defects and geometrical errors between the design and the fabrication.…”