Sb合金化对AE41镁合金耐热性能的影响

采用X射线、光学显微镜、电子探针、扫描电镜等手段研究了Sb合金化对AE41（Mg-4Al-1RE）镁合金组织和耐热性能的影响．结果表明，Sb取代Al优先与RE形成以RE2Sb相为主的高熔点弥散颗粒质点，而枝条状Al11RE3相数量和尺寸减小．Al11RE3相对基体的割裂作用的减弱，RE～Sb质点的弥散强化作用、以及Sb、RE等元素的固溶强化作用，使合金的常温和高温力学性能尤其是塑韧性显著提高，并且有效地改善了高温抗蠕变能力．过量的Sb反而降低了合金的力学性能和耐热性能．合金的断裂为具有塑性特征的准解理断裂．

Influence of antimony addition on heat resistance of AE41 magnesium alloy

Microstructures and heat resistance of AE41(Mg-4Al-1RE)magnesium alloy with Sb additions were investigated.The results show that Sb instead of Al will combine preferentially with RE to form dispersed,high melting point particles which are mainly RE_2Sb phase while the size and amount of the branched intergranular Al_(11)RE_3 reduce.Due to the reduce of split effect of Al_(11)RE_3 phase to the metal base and the dispersion strengthening effect of RE-Sb particles,as well as the solid solution strengthening effect of Sb,RE and other solute elements,mechanical properties especially the plasticity at room and elevated temperature increase greatly,and creep resistance of magnesium alloys also enhances effectively.However,excessive addition of Sb reduces mechanical properties and heat resistance properties. The fracture of the alloy is predominantly quasi-cleavage failure with marked plastic characteristic.