The relation between Mn additions, microstructure and corrosion behavior of new wrought Mg-5Al alloys

Effect of Alloying Mn by Selective Laser Melting on the Microstructure and Biodegradation Properties of Pure Mg

“…Hence alloying Mn into Mg may provide an alloy with good prospects for biomedical applications, when the degradation and the toxicity is taken into consideration. So far, much work has shown that Mg alloys containing Mn have enhanced corrosion resistance [5,[9][10][11][12][13][14]. Gu et al demonstrated that as-cast Mg-1Mn had better strength and corrosion resistance than as-cast Mg [5].…”

“…Ha et al reported that alloying Mn into extruded Mg-8Sn-1Zn-1Al improved corrosion resistance [10]. The following mechanisms have been proposed by which Mn increases corrosion resistance: (i) the grain refinement of the Mg alloy induced by alloying with Mn [11], (ii) the increase of corrosion potential by dissolving the more noble Mn into the Mg alloy [12], (iii) transforming Fe and other impurities into harmless intermetallic 2 of 9 compounds and thereby decreasing local galvanic corrosion [13], and (iv) promoting the formation of the corrosion products in the absence of Mn products [14]. However, further extensive study is still needed.…”

Effect of Manganese on Microstructure and Corrosion Behavior of the Mg-3Al Alloys

“…Cao et al [68] reported ε-AlMn could act as the nucleation site for (αMg) grains due to small lattice mismatch (~4% misfit) against (αMg), and Al 8 Mn 5 (LT) showed no grain refinement in their study due to the bigger lattice mismatch (~20% misfit). In addition, the grain refinement effect of Mn addition was observed in extruded or wrought Mg-Al alloys [18,19,50] and not observed in cast alloys [11,41,69]. This difference may relate to the thermal forming process.…”

“…Corrosion performance is one of the major concerns for applications of magnesium alloys [6,7]. Influences of alloy elements such as Ce [8,9], Nd [9][10][11][12][13], Zn [14,15], Y [11,16], Ca [11,17], and Mn [9,11,15,[18][19][20][21][22][23] on the corrosion behavior of magnesium alloys have been investigated widely in literature. It is widely admitted that Mn addition could combat impure Fe in Mg-Al alloys and reduce corrosion rates of the Mg-Al alloys [11,18,19].…”

“…Using calculated phase diagrams and Scheil solidification, Liu et al [28] reported that the detrimental effect of Fe on the Mg corrosion was caused by the precipitation of the Fe-rich Bcc_B2 phase. Recently, Metalnikov et al [19] experimentally investigated the influence of large Mn addition (0.5, 1.4, 3.1 wt.%) on microstructure and corrosion behavior of the wrought Mg-5Al alloys. The Mg-5Al-0.5Mn alloy was reported to have the best corrosion performance among the alloys in their results, and Al 8 Mn 5 (LT) and (βMn) were identified in the Mn-added alloys.…”