Effect of Sn Addition on Microstructure and Corrosion Behavior of As-Extruded Mg–5Zn–4Al Alloy

Abstract

The effect of Sn addition on the microstructure and corrosion behavior of extruded Mg–5Zn–4Al–xSn (0, 0.5, 1, 2, and 3 wt %) alloys was investigated by optical microscopy (OM), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), electrochemical measurements, and immersion tests. Microstructural results showed that the average grain size decreased to some degree and the amount of precipitates increased with the increasing amount of Sn. The extruded Mg–5Zn–4Al–xSn alloy mainly consisted of α-Mg, Mg32(Al,Zn)49, and Mg2Sn phases as the content of Sn was above 1 wt %. Electrochemical measurements indicated that the extruded Mg–5Zn–4Al–1Sn (ZAT541) alloy presented the best corrosion performances, with corrosion potential (Ecorr) and corrosion current density (Icorr) values of −1.3309 V and 6.707 × 10−6 A·cm−2, respectively. Furthermore, the corrosion mechanism of Sn is discussed in detail.

Corrosion and Wear Performance of Za27/Graphene/B4c Hybrid Nanocomposites Produced by Powder Metallurgy

“…Morphology has a significant effect on the corrosion properties of metallic materials and alloys used in the industry. However, the physical and mechanical resistance of materials and alloys determine the amount of homogeneity in the distribution of the second phase [17][18][19]. Recent studies, showed that the form and content of the reinforcement material in the ZA27 matrix, the production technique of reinforced ZA27 and its hybrid nanocomposites play a very important function on the wear properties of nanocomposites.…”

The role of alloyed strontium in the microstructures and alkaline electrochemistry of Mg–5Al–4Sn alloys

“…Correlatively, XPS measurement indicated that the sturdy passive lm was formed on Sr-containing alloy surfaces with a mixture of oxides/hydroxides from the enriched alloy components, including mainly Mg, Al and Sn products, suggesting an improved corrosion resistance. [54][55][56] Potentiodynamic and potentiostatic polarisation results indicated that the pitting potential, passive potential range and passive stability increased with an increase in the addition of Sr, contributing to the smaller a-Mg grain size, higher density and more continuous precipitates along the grain boundaries, as well as the uniform contribution of alloy elements to the microstructure. As shown in the microstructure analysis, the larger a-Mg grain sizes and sparse and discontinuous precipitates observed on the Mg-5Al-4Sn-based alloy could cause some major gaps between a-Mg and the precipitates, building up the microgalvanic cells that could create good conditions for corrosion initiation and easily develop to force Mg dissolution later on.…”

Effects of Precipitation Hardening Variables on Al–Zn–Mg-Sn Alloy as Sacrificial Anode in Seawater: Experimental and Statistical Analysis

“…It can be stated that increasing the tin composition increased the anode efficiency up till 0.1% Sn in the aluminium alloy (Ige & Umoru, 2007). It has been reported that increasing the tin composition leads to grain refinement and better cathodic performance (Ding et al, 2019 capacity between 2300 and 2700 A-hr/Kg (Suarez et al, 1999). In this study, the calculated Faradaic efficiencies of the aluminium anode alloys containing 0%, 0.01%, 0.05% and 0.1% tin are respectively 2713 A-hr/Kg, 2775 A-hr/Kg, 2684 A-hr/Kg and 2589 A-hr/Kg.…”

“…luminium and its alloys are widely used as sacrificial anode materials in corrosion control for severe environments such as seawater and marine (Yati et al, 2013;Zohdy, 2014;Fagbayi, 2000;Valdez etr al., 2012;El-Hadad etal., 2020;Umoru & Ige, 2007;Ige & Umoru, 2009;Genesca & Juarez, 2007;Zhang, 2014;Ding et al, 2019). The popularity of aluminium as sacrificial anode cathodic protection is due to their cost effectiveness as well as low density, and high current capacity (2980 Ah/kg) (El-Hadad etal., 2020.…”