Enhancing the wettability and interface bonding in carbon nanotubes reinforced 2A70 alloy by the coating of ZrO2.

Novel CNTs modified with ZrO 2 nanoparticles (ZrO 2 @CNTs) were selected as the reinforcement to prepare ZrO 2 @CNTs/2A70 via high-intensity ultrasonic assisted casting. The microstructure, wettability, interfacial bonding, and mechanical properties of ZrO 2 @CNTs/2A70 composites were researched. After modifying ZrO 2 on the surface of CNTs, the contact angle of CNTs to 2A70 melt reduced from 140.70° to 116.85°. Thermodynamic calculation indicated that the wetting processes of ZrO 2 nanoparticles were spontaneous in initial stage, and then required additional energy from external environment. TEM analysis demonstrated that ZrO 2 nanoparticles were uniformly distributed on the surface of CNTs, and could lock the CNTs in matrix, enhancing the interfacial bonding of CNTs-Al. The (010)ZrO 2 //(010)Al, (010)ZrO 2 //(100)Al, (010)ZrO 2 //(100)Al can form semi-coherent interface, indicating a good lattice space matching between ZrO 2 and Al matrix. The 1.5 wt% ZrO 2 @CNTs/2A70 composites manifested excellent mechanical properties and the ultimate tensile strength reached 256.2 MPa, which were 21.47 % higher than that of the matrix (210.9 MPa). The improved mechanical properties may be attributed to the efficient load transfer of ZrO 2 @CNTs. [Display omitted] • A novel CNTs modified with ZrO 2 nanoparticles are successfully prepared. The contact angle of CNTs to Al reduced from 140.70° to 116.85°. • The (010)ZrO 2 //(010)Al, (010)ZrO 2 //(100)Al, (010)ZrO 2 //(100)Al form semi-coherent interface, indicating a good lattice space matching between ZrO 2 and Al. • 1.5 wt% ZrO 2 @CNTs/2A70 composites exhibited excellent mechanical properties. [ABSTRACT FROM AUTHOR]