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利用喷射成形技术制备了Mg12Al1.5Zn6.5Ca1Nd镁合金,采用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)等测试手段,研究了挤压态实验合金的微观组织及力学性能。结果表明:挤压态实验合金组织主要由α-Mg和Al2Ca组成,合金组织为等轴晶,晶粒大小约为2μm,第二相Al2Ca颗粒主要弥散分布在晶界处,颗粒平均尺寸小于1μm;基体内存在位错网及位错塞积,Al2Ca相中存在孪晶结构;合金抗拉强度(σb)、屈服强度(σ0.2)、延伸率(δ)分别为470 MPa、350 MPa、4.7%,主要强化方式为细晶强化、弥散强化、固溶强化;断口存在微孔聚合形成的孔洞,孔洞底部的杂质相或孔洞周围硬脆相与基体之间易萌生微裂纹,合金断裂机制为微孔聚合型沿晶断裂。
The Mg12Al1.5Zn6.5Ca1Nd magnesium alloy was prepared by spray forming technique. The microstructure of the extruded alloy was studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) And mechanical properties. The results show that the microstructure of the as-extruded alloy is mainly composed of α-Mg and Al2Ca. The microstructure of the alloy is equiaxed and the grain size is about 2μm. The second phase Al2Ca particles are mainly dispersed in the grain boundaries and the average particle size is less than 1μm ; The dislocation network and dislocated plug product exist in the matrix, and the twin structure exists in Al2Ca phase. The tensile strength (σb), yield strength (σ0.2) and elongation (δ) of the alloy are 470 MPa, 350 MPa, 4.7%. The main strengthening methods are fine grain strengthening, dispersion strengthening and solid solution strengthening. The pores formed by micropore polymerization at the fracture surface, the impurity phase at the bottom of the pores or the micro-cracks between the hard and brittle phases around the pores and the matrix, Microporous polymeric intergranular fracture.