氧化镁包覆CNTs增强的AZ91D基复合材料的力学性能

Mechanical Properties of AZ91D Alloy Reinforced by Carbon Nanotubes Coated MgO

采用粉末冶金与热挤压工艺制备了包覆MgO碳纳米管增强的AZ91D基复合材料。研究了包覆MgO的CNTs对复合材料力学性能的影响规律,并利用扫描电镜对CNTs/AZ91D复合材料断口形貌进行了观察和分析。结果表明,包覆MgO后的CNTs对AZ91D镁合金有较强的增强效果,当MgO-CNTs含量为3.0%时,CNTs/AZ91D复合材料抗拉强度、伸长率和显微硬度(HV)都达到最大值,分别为256.7 MPa、12.75%和130.86,比基体合金提高了41.44%、41.67%和22.4%。但是,当MgO-CNTs加入量过多时,会因团聚而影响增强效果,复合材料力学性能下降。

Carbon nanotubes coated MgO reinforced AZ91D composites were fabricated by powder tech- nique combined with hot extrusion process. The mechanical properties of the composites prepared were tested, and effects of MgO-CNTs on the mechanical properties of the AZglD alloy composites were ana- lyzed, and the fractograph was observed and analysed by scanning electron microscope. The results re- veal that the MgO coated CNTs can strengthen mechanical properties of the composites effectively. When the addition of MgO-CNTs is 3. 0% the tensile strength, elongation and microhardness of the composites reach 256.7 MPa, 12. 75% and 130.86HV, respectively, increased by 41.44%, 41.67% and 22.4%, respectively, compare to those of the AZglD alloy. However, with the excessive addition of MgO-CNTs, the MgO-CNTs will be cool, resulting in decrease of mechanical properties.