Achieving uniform plasticity in a high strength Al-Mn-Sc based alloy through laser-directed energy deposition

Review on laser directed energy deposited aluminum alloys

“…Thus, outstanding strength-plasticity synergy in the as-build state can realize further strengthening after direct aging. Analogously, Xiao et al [160] added Sc and Zr in LDED Al-Mn-Mg alloy, and both the as-built and heat treated samples acquired excellent strength-plasticity synergy, with the UTS reaching 519 MPa after heat treatment. Moreover, some investigations studied the optimization of Al-Mg alloys by adding Sc/Zr and Ti-based reinforcement together [120,183].…”

“…In-situ alloying of elements in Al alloys during LDED can affect the solidification behavior, grain growth, and precipitation [158]. For instance, adding Sc and Zr has attracted wide attention due to their excellent effects on changing the solidification range, refining microstructures, and precipitate strengthening [31,150,[159][160][161][162]. The maximum solid solubility of Sc and Zr in Al is only 0.35 wt.% and 0.26 wt.%, respectively [163,164], but rapid solidification can increase the amount of Sc and Zr in the Al matrix by several orders of magnitude [164,165].…”

“…The maximum solid solubility of Sc and Zr in Al is only 0.35 wt.% and 0.26 wt.%, respectively [163,164], but rapid solidification can increase the amount of Sc and Zr in the Al matrix by several orders of magnitude [164,165]. Xiao et al [160] found that in-situ formed primary Al 3 (Sc, Zr) particles can precipitate in the melt pool inner region and melt pool boundary of as-deposited Al-Mn-Mg-Sc-Zr alloy. Wang et al [31] found that the fraction of in-situ formed particles at the fusion boundary was approximately twice that of the interior of the melt pool, and the overall content of Al 3 (Sc, Zr) particles increased with the increase of Sc/Zr content, as shown in figures 13(a)-(d).…”

“…[39]. Sc, Zr, and reinforcement particles are often used to improve the printability and formability of LDED Al-Mg alloys, and the subsequent strength-plasticity synergy in as-built conditions can be improved significantly [150,159,183,207], which can achieve the highest level of strength in the wide series [20,38,119,147,194,209]; Al-Mn alloy [160]; Al-Si alloy [34-36, 59, 67, 68, 76, 113, 145, 204, 217]; Al-Mg alloy [39,120,150,159,183,207]; Al-Mg-Si alloy [218]; Al-Zn alloy [37,64,78,88,96,112,181], Al-Cr alloy [203]), and (b) post-heat-treated (Al-Cu alloy [38,194], Al-Mn alloy [160], Al-Si alloy [36], Al-Mg alloy [120,150], Al-Mg-Si alloy [148,218], and Al-Zn alloy [37,64,96,112,181]).…”

“…Grain boundary strengthening mainly results from grain boundary obstruction to dislocation movement, which can be quantified by the Hall-Petch formula [160,232]:…”