Effect of ball-milling time on mechanical and magnetic properties of carbon nanotube reinforced FeCo alloy composites

Publication date: 15 May 2017
Source:Materials & Design, Volume 122
Author(s): Amar J Albaaji, Elinor G Castle, Mike J Reece, Jeremy P Hall, Sam L Evans
Carbon nanotubes (CNTs) reinforced FeCo alloys were produced by high energy ball-milling and spark plasma sintering (SPS). CNTs distribution in the FeCo alloy was gradually improved as ball-milling time increased, with a uniform dispersion achieved after 6h ball-milling. Tensile tests demonstrated that, as the ball-milling time increased, the yield strength increased in the composites; a maximum 50% relative increase in tensile strength due to the addition of CNTs was achieved after 1h ball-milling, which then decreased with further ball-milling. The elongation to fracture was significantly increased after 1h ball-milling and then decreased with further ball-milling. SEM results show a patch of dimples in the fracture surface of the composite, indicating improved ductility due to CNTs. The coercivity was increased with increased ball-milling time, while the saturation induction showed a peak value after 1h of ball-milling and then decreased with further ball-milling. Raman spectra of the composite indicated that no serious damage had been imparted to the CNTs during ball-milling.

Graphical abstract

http://ift.tt/2mCHQHn