Mechanical, corrosion and cavitation erosion properties of LM 9 grade aluminium – multi-walled carbon nanotubes composites

ABSTRACT

This paper is intended to study mechanical, corrosion and cavitation erosion properties of aluminium metal matrix composites with Multiwalled carbon nanotubes (MWCNTs) as reinforcement. Multi-walled carbon nanotubes in different weight percentages (1, 2 and 3%) are reinforced in Light metal 9 (LM 9) aluminium alloy using the ultrasonic stir casting method. Hardness, pitting corrosion potential and erosion resistance are evaluated to assess the influence of different weight percentages of MWCNTs as reinforcements in LM 9 alloy. The results indicate that Aluminium – MWCNTs composites possess an improved hardness of up to 150 % compared to base LM 9 alloy. The pitting corrosion resistance of composites was found to be excellent with minimum corrosion damage to the composite specimen. Cavitation erosion test performed as per ASTM G32 indicates a decrease in erosion wear for composites reinforced with MWCNTs compared to base material LM 9. The property improvement of the LM 9 – MWCNT composite under dynamic conditions is verified using SEM micrographs. The effect of weight percentage of MWCNTs found to be significant in the enhancement of properties.  There are 16 % and 30 % reductions respectively in pitting corrosion potential and erosive wear respectively for composite with 3 % MWCNTs.

KEYWORDS:

• Aluminium alloy LM 9
• multi-walled carbon nanotubes
• composite
• hardness
• pitting corrosion
• cavitation erosion

Acknowledgments

The authors deeply thank IIT Guwahati for their assistance in the characterization of nanocomposite samples. The authors thank the authorities of GITAM (Deemed to be university) India for their support extended for conducting research.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Notes on contributors

Srinivas V.

Srinivas V. is a professor in Mechanical Engineering GITAM (Deemed to be University), India. His research interests are nanofluids for lubricant & coolant applications and nano coatings & nano composites for IC engines.

Jayaraj A.

Jayaraj A. is an Associate professor in the department of Mechanical Engineering, Miracle school of Engineering, Visakhapatnam, India.  His areas of interest are nano-composites and finite element analysis.

Venkataramana V.S.N.

Venkataramana V.S.N. is an Associate Professor in The Department of Mechanical Engineering, GITAM (Deemed to be University), Visakhapatnam, India.  His research interests are composites, welding technology and material characterisation.

Ravisankar H.

Ravisankar H. is a professor in Mechanical Engineering GITAM (Deemed to be University), India. His research is focused on nano composites for biomedical applications.

Moorthy Ch. V. K. N. S. N.

Moorthy Ch. V. K. N. S. N. is a professor in the Department of Mechanical Engineering, Institute of aeronautical Engineering, Hyderabad. His research interests are in heat transfer, material characterisation and CFD.