Effect of sol–gel prepared nanoalumina reinforcement content on the corrosion resistances of Al 6061‐Al2O3 nanocomposite in 3.5% NaCl solution. Issue 10 (24th May 2017)

• Record Type: Journal Article
• Authors: Shrivastava, V.; Singh, A.; Singh, I. B.
• Is Part Of: Materials and corrosion. Volume 68:Issue 10(2017)
• Page Start: 1099
• Page End: 1106
• Publication Date: 2017-05-24
• Subjects: 3.5% NaCl solution -- Al‐6061 alloy -- corrosion -- metal matrix composite -- nanoalumina reinforcement; Materials -- Periodicals; Metals -- Periodicals; Corrosion and anti-corrosives -- Periodicals; 620.1122305
• DOI: 10.1002/maco.201709469
• Languages: English
• ISSNs: 0947-5117

Abstract

Abstract : Sol–gel prepared nanoparticles of pure alpha alumina with 0.5, 1.0, 1.5, 2.0, and 2.5 wt% content were used in the synthesis of Al‐6061 alloy based metal matrix composite via powder metallurgy route. After synthesis, corrosion investigation of the synthesized composite samples were carried out in 3.5% NaCl solution using electrochemical polarization and impedance analysis. A total of 0.5–1 wt% nanoalumina reinforced composite has shown an excellent corrosion resistance of more than an order of magnitude higher as compared to the sintered base alloy. However, a substantial decrease in corrosion resistances of synthesized composite were found after reinforcement of >1.0 wt% nanoalumina and corrosion becomes worse than the sintered base alloy of 2.5 wt% nanoalumina incorporated composite sample. Microstructural examination and relative density measurements of the synthesized composites indicated that increase of porosities and accumulation of nanoparticles in the grain boundary regions conjointly increase the corrosion reaction after exceeding 1.0 wt% nanoalumina reinforcement content. Abstract : Reinforcement of 0.5 wt% sol–gel prepared nanoalumina particles with Al‐6061 alloy increases the corrosion resistance of the synthesized nanocomposite in 3.5% NaCl solution more than 30 times. Exceeding 2 wt% of nanoalumina reinforcement results in a steep increase of corrosion rate and corrosion becomes worse than the base alloy after 2.5 wt% of reinforcement of nanoparticles.