Structural and Corrosion Study of Uncoated and Zn-Cu Coated Magnesium-Based Alloy

Abstract

Zn-Cu alloy was deposited onto AZ63 substrate, and the corrosion behaviour of resulting modified electrodes was investigated in 3 wt % NaCl solution in comparison with uncoated AZ63. Electrochemical, structural, and morphological study of the coating is presented. SEM images reveal that the surface morphology of the films is uniformly small spherical grain distributions. The XRD patterns illustrate polycrystalline structure and the formation of peaks corresponding to hexagonal close-packed ε-phase of Zn-Cu with various crystallographic orientations. Cyclic voltammetry was used to determine the potential ranges where the various redox processes occur. Linear sweep voltammetry results illustrate that longer exposure of uncoated AZ63 in NaCl solution produces a greater corrosion potential shift because of the formation of an oxide layer that did not prevent the progression of corrosion attack. The corrosion resistivity of Zn-Cu coated AZ63 is approximately two orders of magnitude greater than that of uncoated AZ63.

Wear Resistance Improvement of Copper Alloys Using a Thermochemically Obtained Zinc-Rich Coating

“…The results report the presence of a Cu5Zn8 -like structure, phase (JCPDS 65-6566, crystal system cubic, space group I43m, cell parameter 8.85-8.89 Å). These results agree with literature [22][23][24][25][26][27][28][29][30][31], and show the presence of the γ phase of the Zn-Cu system, which is a harder phase.…”

“…In the case of bronze, the X-Ray analysis show the formation of a cubic structure of Copper Zinc (Cu64Zn36, JCPDS card No 50-1333) with Miller's index equal to a=b=c=3.69612 Å and a phase Cu5Zn8 (JCPDS 65-6566, crystal system cubic, space group I43m, cell parameter 8.85-8.89 Å). It is confirmed for brass case and according to various references [22][23][24][25][26][27][28][29][30][31], the presence of γ phase of the Cu-Zn system. Also, a cubic structure of Copper Oxide in which a=b=c= 4.26960 Å is perceived.…”

“…This loss of symmetry, coupled with the fact that in γ brass, is obtained the maximum amount of distortion, will probably account for the exceptional hardness of γ brass as compared with the hardness of the other alloys in the series. As discussed in [22][23][24][25][26][27][28][29][30][31], the complex crystalline structure of this phase is associated with a high defect density that would also contribute to greater coating hardness. Both coated materials show a linear relationship between their microhardness and the distance from the surface, in the case of bronze there is a correlation index of 0.41, for brass a value of 0.69 is obtained.…”

In‐situ formation of an efficient trimetallic (CuZnAg) electrocatalyst for water oxidation

“…The peak at 30.3 ° (♣) in Figure 3 corresponds to the deposition of Cu. Five distinct signals appearing at 34.3° (♦), 36.98 ° (♦), 39.6 ° (♦), 49.8 ° (♦) and 52.40 ° (♦) can be related to the deposition of CuZn alloy (brass) according to the data documented in the literature 36,57‐59 . The crystallite size of the catalyst was determined using Scherrer formula from two main XRD peaks at 2 θ of 24.44° and 34.31° and the average crystallite size was calculated to be 80 nm.…”

Development of a Binder-Free Tetra-Metallic Oxide Electrocatalyst for Efficient Oxygen Evolution Reaction

“…Another factor that governs the quality of metal oxide alloy formation is the respective deposition time. Lastly, the applied potential also plays an important role in determining the quality of the deposited material [1,11,[34][35][36][37][38][39][40][41][42].…”