Additions of Rare Earth metals (including Sc and Y) are known to improve specific properties of both Al- and Mg-alloys. In aluminum alloys, scandium increases specific strength, plasticity, durability and formability and reduce hot-cracking of welded alloys. For magnesium alloys, the addition of scandium is mainly beneficial for the creep resistance and the high temperature stability. This is particularly true in the case with additional elements like Mn and Cc [1]. Rare earth additions improve the thermal stability, creep resistance and corrosion behavior together with good casting properties of the Mg alloys. Von Buch et al. [1] have shown that Mg-Mn-Sc-alloys reach creep rates up to two orders of magnitude lower than commercial WE43 alloys. Secondary creep rates of these alloys are comparable to WE43 at higher stresses but lower at lower stresses. Precipitates of Mn_2SC - that are predicted by thermodynamic calculation - are found to be responsible for these good mechanical properties.
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机译：已知罕见地添加稀土金属（包括SC和Y），以改善Al-and Mg-合金的特定性质。在铝合金中，钪升高了比强度，可塑性，耐用性和可成型性，减少了焊接合金的热破裂。对于镁合金，添加钪主要有利于蠕变性和高温稳定性。在诸如Mn和Cc [1]的附加元素的情况下，这尤其如此。稀土添加改善了热稳定性，蠕变性和腐蚀行为以及镁合金的良好铸造性能。 von buch等人。 [1]显示Mg-Mn-Sc-合金达到比商业WE43合金低的蠕变速率高达两个数量级。这些合金的二次蠕变速率与较高应力的We43相当，但在较低的应力下较低。通过热力学计算预测的Mn_2SC的沉淀物 - 被发现对这些良好的机械性能负责。
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