Effects of cooling rate on the microstructure and properties of hot-dipped Zn–Al–Mg coatings

Xu, Minyun; Han, Dong Suk; Zheng, Zhaoyang; Ma, Ruina; Du, An; Fan, Yongzhe; Zhao, Xue; Cao, Xiaoming

doi:10.1016/j.surfcoat.2022.128665

Cited by 28 publications

(9 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Combined with Figure 3, these observations suggest that B additions refine the eutectic structure on the coating's surface. Given that the primary corrosion product, basic zinc chloride, precipitates preferentially on the eutectic structure, [30] this can…”

Section: Corrosion Products Characterizationmentioning

confidence: 99%

The Effects of B on the Microstructure and Corrosion Resistance of Zn–6Al–3Mg Alloy Coating

Chen,

Liu,

et al. 2024

steel research int.

View full text Add to dashboard Cite

Hot dip galvanized zinc‐aluminum‐magnesium steel plates are widely used in fields such as power communication, automotive manufacturing, and marine engineering due to their excellent corrosion resistance. The use of microalloying can further improve their corrosion resistance. The effects of B on the microstructure and corrosion resistance of Zn–6Al–3Mg (ZAM) alloy coatings are systematically examined. Data indicates that the eutectic structure of the coating progressively refines as B content increases, concomitant with a reduction in the thickness of the Fe2Al5 inhibition layer owing to the augmented formation of an Al‐rich phase at the surface. When the addition of B reaches 0.12%, the microstructure of the alloy coating is minimized, and there is no further reduction in the thickness of the Fe2Al5 inhibition layer. Moreover, the presence of B diminishes the corrosion current density and bolsters corrosion resistance. Optimal corrosion performance, indicated by maximal density and uniformity of surface corrosion products and the lowest corrosion current density, is achieved at a B addition of 0.12%. The judicious selection of B content is pivotal for enhancing the microstructural and anti‐corrosive properties of ZAM alloy coatings. Therefore, adding 0.12% B to ZAM alloy can effectively improve the microstructure and corrosion resistance of the alloy coating.

show abstract

Section: Corrosion Products Characterizationmentioning

confidence: 99%

The Effects of B on the Microstructure and Corrosion Resistance of Zn–6Al–3Mg Alloy Coating

Chen,

Liu,

et al. 2024

steel research int.

View full text Add to dashboard Cite

show abstract

“…The CPE can be calculated using equa- 10a). The first time constant in the high-frequency (HF) region corresponds to the corrosion product formed on the coating-layer surface, whereas the second time constant in the low-frequency (LF) region corresponds to the corrosion resistance at the corrosion product/coating interface [45]. The electrochemical parameters estimated from the fitted EIS results (Figure 10b) of all the samples are summarized in Table 6.…”

Section: Corrosion Performance 361 Potentiodynamic Polarizationmentioning

confidence: 99%

Effects of the Mg Content on Microstructural and Corrosion Characteristics of Hot-Dip Al–Si–Mg Alloy-Coated Steel Sheets

Jin,

2023

Materials

View full text Add to dashboard Cite

Hot-dip Al–Si alloy coatings with excellent resistance to corrosion and high-temperature oxidation have emerged as promising lightweight substitutes for conventional corrosion-resistant coatings. The introduction of Mg can be an effective strategy for enhancing the sacrificial protection capability of Al–Si coatings. In this study, the effects of Mg addition on the morphology, electrochemical behavior, and mechanical properties of Al–Si coatings were investigated, along with the Mg-content optimization of the coating layer. Adding Mg promoted the formation of finely distributed eutectic intermetallic phases, such as Al/Mg2Si and the primary Mg2Si phase. Notably, the Mg2Si phase coarsened significantly when ≥15 wt.% of Mg was added. In addition, an Al3Mg2 intermetallic compound was observed in coating layers containing >20 wt.% of Mg, reducing the adhesion of the coating layers. Samples containing 5–10 wt.% of Mg exhibited excellent corrosion resistance (owing to a uniform distribution of the fine eutectic Al/Mg2Si phase and the formation of stable corrosion products), whereas those containing 20 wt.% of Mg exhibited unremarkable corrosion resistance (owing to the formation of an Al3Mg2 phase that is susceptible to intergranular corrosion).

show abstract

“…In addition, a study by Minyun Xu et al [15] highlights the importance of optimal hot-dip-coating process parameters for enhancing the crack resistance and corrosion resistance of Zn-Al-Mg coatings. Five different Zn-6Al-3Mg coatings were prepared using varying cooling rates: ZAM1 (0.1 • C/s), ZAM2 (1 • C/s), ZAM3 (5 • C/s), ZAM4 (30 • C/s), and ZAM5 (400 • C/s).…”

Section: Introductionmentioning

confidence: 99%

“…Previous studies have focused on the MgZn 2 phase within Zn-Al-Mg coatings, considered a crucial factor in enhancing these coatings’ corrosion resistance [ 3 , 12 , 13 ]. However, as research progresses, some studies have also identified the presence of the Mg 2 Zn 11 phase, indicating that the phase composition of these coatings is more complex than expected [ 8 , 14 , 15 , 16 , 17 ]. These findings have sparked the need for a deeper exploration of the phase transformation mechanisms occurring within these coatings, especially the transformation from MgZn 2 to Mg 2 Zn 11 and its specific impact on coating performance.…”

Section: Introductionmentioning

confidence: 99%

Thermodynamic Simulation Calculations of Phase Transformations in Low-Aluminum Zn-Al-Mg Coatings

Zhang,

Zhao

et al. 2024

Materials

View full text Add to dashboard Cite

This study delves into the formation, transformation, and impact on coating performance of MgZn2 and Mg2Zn11 phases in low-aluminum Zn-Al-Mg alloy coatings, combining thermodynamic simulation calculations with experimental verification methods. A thermodynamic database for the Zn-Al-Mg ternary system was established using the CALPHAD method, and this alloy’s non-equilibrium solidification process was simulated using the Scheil model to predict phase compositions under varying cooling rates and coating thicknesses. The simulation results suggest that the Mg2Zn11 phase might predominate in coatings under simulated production-line conditions. However, experimental results characterized using XRD phase analysis show that the MgZn2 phase is the main phase existing in actual coatings, highlighting the complexity of the non-equilibrium solidification process and the decisive effect of experimental conditions on the final phase composition. Further experiments confirmed that cooling rate and coating thickness significantly influence phase composition, with faster cooling and thinner coatings favoring the formation of the metastable phase MgZn2.

show abstract

Effects of cooling rate on the microstructure and properties of hot-dipped Zn–Al–Mg coatings

Cited by 28 publications

References 49 publications

The Effects of B on the Microstructure and Corrosion Resistance of Zn–6Al–3Mg Alloy Coating

The Effects of B on the Microstructure and Corrosion Resistance of Zn–6Al–3Mg Alloy Coating

Effects of the Mg Content on Microstructural and Corrosion Characteristics of Hot-Dip Al–Si–Mg Alloy-Coated Steel Sheets

Thermodynamic Simulation Calculations of Phase Transformations in Low-Aluminum Zn-Al-Mg Coatings

Contact Info

Product

Resources

About