Accessible Unlicensed Requires Authentication Published by De Gruyter February 23, 2021

An investigation of corrosion behavior of Al–B4C nanocomposites in various corrosive solutions

Mahboobeh Azadi, Mohammad Arab and Omid Mirzaee

Abstract

In this paper, the corrosion behavior of Al-B4C nanocomposites made by stir casting is investigated. The corrosive environments included 0.1 M HCl, 0.6 M NaCl, 0.03 M H3BO3, and 2 M NaOH solutions. Both the optical microscopy and the field emission scanning electron microscopy methods were used for the microstructural investigation. The X-ray diffraction and the energy dispersive spectroscopy techniques were utilized to detect phases. Tafel polarization results showed that the corrosion rate for the Al-B4C nanocomposites reduced by about 94.0 -99.7% in comparison with the aluminum alloy in 0.1 M HCl and 0.6 M NaCl solutions; however, this decrease was 20.4 - 57.1% in 0.03 M H3BO3 solution. Moreover, the electrochemical impedance spectroscopy results demonstrated that for nanocomposites the total increase in the charge transfer resistance increased to 80.7% compared to the aluminum alloy in 0.1 M HCl solution after 72 h. The Al-B4C nanocomposite that was stirred for 6 mins at 8000C exhibited higher corrosion resistance than other samples after 72 h in 0.6M NaCl. However, the sample suggested for all utilized corrosive solutions was the nanocomposite made at 750 0C and stirred for 6 mins, based on the lower crystallite size of a-Al phase.

Published Online: 2021-02-23
Published in Print: 2020-12-01

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