粉末烧结对Mg-Sc合金微观组织和力学性能的影响

Effect of powder sintering on microstructure and mechanical properties of magnesium‒scandium alloys

在惰性气氛下,经500℃烧结2 h和300℃挤压制得镁钪合金,并对其进行微观组织观察和力学性能测试。结果表明:粉末烧结镁钪合金的相组成主要为基体Mg相,未发现Mg-Sc相生成。在粉末烧结过程中,钪元素在镁基体中发生扩散,明显改善界面结合形式,提高了镁钪界面的结合性。当钪质量分数为1.0%时,镁钪合金的伸长率达到10.37%,提高了61%。在拉伸试样断口处发现大量韧窝存在,说明烧结处理可明显提高镁钪合金的韧性。

Magnesium‒scandium(Mg‒Sc)alloys were prepared by powder sintering at 500℃for 2 h and extrusion at 300℃under the inert atmosphere.The microstructure and mechanical properties of the Mg‒Sc alloys were investigated.The results show that,the phase composition of the Mg‒Sc alloys is mainly Mg phase,and no Mg‒Sc phase is detected.Due to the diffusion of Sc element in the Mg matrix during the sintering process,the interfacial combination is significantly improved,and the interface bonding between Mg and Sc particles is increased.The elongation of the sintered Mg‒Sc alloys with the Sc mass fraction of 1.0%is 10.37%,which is increased by 61%.In addition,a large number of dimples are observed at the tensile fracture,indicating that sintering can improve the toughness of the Mg‒Sc alloys.