Compelling mechanical properties of carbon nanotubes reinforced pure magnesium composite by effective interface bonding of Mg2Ni

• Published in: Journal of alloys and compounds Vol. 727; pp. 963 - 969
• Main Authors: Han, Guoqiang, Du, Wenbo, Ye, Xiaoxin, Liu, Ke, Du, Xian, Wang, Zhaohui, Li, Shubo
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 15.12.2017; Elsevier BV
• Subjects: Bonding strength; Carbon nanotubes; Chemical elements; Crack propagation; Cracks; Interface bonding; Load transfer; Magnesium; Mechanical properties; Metal matrix composites; Mg2Ni phase; Microstructure; Nickel; Particulate composites; Solution strengthening; Studies; Tensile strength; Ultimate tensile strength; Interface bonding; Mechanical properties; Metal matrix composites; Mg2Ni phase; Microstructure
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2017.08.133

In this study, a kind of nickel coated carbon nanotubes (Ni-CNTs) reinforced pure magnesium (Mg) matrix composite was prepared using two-step process. The nano-Mg2Ni phase at the interface was in-situ formed to improve the interface bonding between CNTs and Mg matrix. Results indicated that the yield and ultimate tensile strength of 2.0 wt. % Ni-CNTs/Mg composite were 278.3 MPa and 304.5 MPa, respectively, showing 77% and 48% increase in comparison with those of 2.0 wt. % CNTs/Mg composite. The remarkably enhanced mechanical properties were attributed to the strong interface bonding due to the in-situ formed nano-Mg2Ni phase. The corresponding strengthening mechanisms were regarded as the coupling interface effect of the coherent interface and the interstitial solid solution. Moreover, the CNTs acted as a bridging role in load transfer and obstructed the growth of cracks in Ni-CNTs/Mg composites. •The 305 MPa UTS of Ni-CNTs/Mg composite is the highest in pure Mg matrix composite.•The nano-Mg2Ni phase was in-situ formed at the interface of Ni-CNTs/Mg composite.•Mg2Ni phase produce a coupling of coherent interface and interstitial solid solution.•The coupling interface resulted in strong bonding force and efficient load transfer.