Hybrid carbon nanomaterials reinforced magnesium matrix composite with simultaneously improved thermal and mechanical performances

Hybrid carbon nanomaterials (HCNs) with highly stable dispersion were synthesized with graphene nanoplatelets (GNPs), carbon nanotubes (CNTs), and carbon blacks (CBs) in a mass ratio of 3:1:4 through ultrasonication in ethanol. The settlement ratio (24 h) of HCNs (7 %), determined from UV-Vis adsorption spectra, was significantly lower than that of single CNs (＞89 %), and the dispersion remained stable for over 30 days. In this hybrid system, CNTs acted as 1D spacers to prevent GNP agglomeration, while CBs served as 0D spacers to fill the gaps between GNPs and CNTs. This HCN network not only ensured the uniform dispersion of single CNs but also established interconnected thermal and mechanical conduction pathways within the HCN/ZK61 composite. Compared with ZK61 alloy, HCN/ZK61 composite exhibited a TC of 133 W/(m·K), representing an improvement of 26.67 %. The contributions of GNPs, CNTs, and CBs to the TC of HCN/ZK61 composite were calculated to be 60.88 %, 31.83 %, and 7.29 %, respectively. HCN/ZK61 composite achieved tensile yield strength of 310 MPa and elongation of 28.4 %, corresponding to improvements of 28.63 % and 66.08 %, respectively, than ZK61 alloy. This hybrid strategy of utilizing CNs as reinforcements expands the potential applications of Mg alloys in functional and structural fields.

Duke Scholars

Author Zhaohui Wang Pathology