原位合成CNTs/Cu-Al2O3复合材料的性能研究

对Al的质量分数分别为0.20%，0.35%，0.60%的Cu-Al合金粉末进行内氧化，得到Cu-Al₂O₃粉末。采用化学气相沉积法在Cu-Al₂O₃粉末表面原位生长碳纳米管(carbon nano tubes, CNTs)，采用放电等离子烧结工艺成功制备了CNTs/Cu-Al₂O₃复合材料。采用扫描电子显微镜和透射电子显微镜观察了CNTs/Cu-Al₂O₃复合粉末、复合材料断口的形貌。采用显微硬度计、微拉伸试验机、摩擦磨损试验机分别对纯Cu及复合材料的维氏硬度、抗拉强度、摩擦因数进行测试。采用电化学工作站测试复合材料在3.5%NaCl (质量分数)水溶液中的耐腐蚀性能。结果表明，随着Al的质量分数的增加，粉末表面合成的CNTs的数量也增多。Al的质量分数为0.35%时，CNTs/Cu-Al₂O₃复合材料的综合性能最佳，与纯Cu相比，复合材料的抗拉强度和腐蚀电势分别提高了86.4%和43.2%，分别为315 MPa和-0.268 V，摩擦因数降低了53.3%，仅为0.28。

Study on the properties of in-situ synthesized CNTs/Cu-Al2O3 composites

Cu-Al₂O₃ powder was obtained by internal oxidation of Cu-Al alloy powder with mass fraction of 0.20%, 0.35% and 0.60%Al. Carbon nanotubes (CNTs) were in-situ grown on the surface of Cu-Al₂O₃ powder by chemical vapor deposition, and CNTs/Cu-Al₂O₃ composites were successfully prepared by spark plasma sintering. The composite powder and the fracture morphology of composite material were observed by scanning electron microscope and transmission electron microscope. The hardness, tensile strength, and friction coefficient of Cu and its composite materials were tested by microhardness tester, micro-tensile tester, and friction and wear tester. The corrosion resistance of the composite material in 3.5% NaCl (mass fraction) aqueous solution was tested by electrochemical workstation. The results show that the number of CNTs synthesized on the powder surface increased with the increase of Al mass fraction. When the mass fraction of Al is 0.35%, the comprehensive properties of CNTs/Cu-Al₂O₃ composite are the best. Compared with pure copper, the tensile strength and corrosion potential of the composite are increased by 86.4% and 43.2%, respectively, which are 315 MPa and -0.268 V, respectively. The friction coefficient is reduced by 53.3%, which is only 0.28.