旋转摩擦挤压加工CNTs/Al复合材料的线材组织和性能

摘要

Carbon nanotubes (CNTs) reinforced aluminum matrix composite wires containing 0,3.8％,4.5％ and 5.3％ CNTs (volume fraction) were prepared by rotational friction extruded processing (RFEP).The microstructures,mechanical property and electric property were characterized by scanning electron microscopy and transmission electron microscopy.The results show that the grains of composite wires are elongated and grow after RFEP,but the grain size is still remained in extra fine scale.CNTs are homogenously distributed in the aluminum matrix,and some CNTs are orientational aligned along the extrusion direction in the composites.With the content of the CNTs increasing,the microhardness,tensile strength and electrical resistivity increase,respectively,and all of these are higher than those of FSP composite blocks.%采用旋转摩摞挤压加工方法制备体积分数分别为0、3.8％、4.5％和5.3％(体积分数)的碳纳米管增强铝基复合材料线材,进行复合材料线材显微组织观察和力学、电学性能分析.结果表明:经旋转摩擦挤压后,复合材料线材的晶粒较搅拌摩擦加工试样有所拉长和长大,但仍为超细晶结构;复合材料线材中的碳纳米管沿着挤压方向呈取向排列均匀分布于铝基体中.随着碳纳米管体积分数的增加,复合材料线材的显微硬度、抗拉强度以及电阻率均逐渐增加,且均高于同CNTs体积分数的搅拌摩擦加工块体复合材料试样,但塑性有所降低.