Effect of Na2WO4 Concentration on the Microstructure and Corrosion Behavior of Ni-W-P Ternary Alloy Coatings

Abstract

Ni-W-P ternary coating was successfully deposited on AZ91D magnesium alloy by electroless plating with low energy consumption. The effect of Na 2 WO 4 concentration on the microstructure, deposition rate, corrosion behavior, adhesion force, porosity test and micro-hardness of Ni-W-P ternary coatings were evaluated. Results reveal that when the concentration of Na 2 WO 4 is 15 g/L in the plating solution, the coating with the average thickness of 17 μm is uniform and dense, and the content of phosphorus and tungsten reached 9.63 wt.% and 1.14 wt.% respectively, which presents amorphous structure. Meanwhile, when the concentration of Na 2 WO 4 is 15 g/L, the amorphous Ni-W-P ternary coating has the best corrosion resistance, among which E corr is -0.326 V, I corr is 0.003 A/cm 2 in 3.5 wt.% NaCl solution. In addition, the mechanisms of corrosion resistance for the substrate and the coating were exploded.

Biriktirme Süresinin Akımsız Nikel-Bor Kaplamaların Sertlik ve Korozyon Özelliklerine Etkisi

“…When the peaks at approximately 44° of the coating layers produced with electroless coating are examined, it is clearly seen that the peak intensity becomes sharper with the increase in the the deposition times of the coatings. Also, , the Ni peak (200) at approximately 53° indicates the presence of both amorphous and crystalline structures for the deposition time of 90 min (Tian, Sun, Liu, Jia, & Xiao, 2021). Grain size was calculated using the XRD data with the Scherrer equation (Patterson, 1939) below.…”

Akımsız Kaplama Yöntemi ile Üretilen Ni-W-P Çoklu Alaşımların Sertlik ve Aşınma Özelliklerine Sodyum Tungsten İçeriğinin Etkisi

“…Akımsız kaplama ile üretilen kaplama tabakalarının yaklaşık 44°'deki pikleri incelendiğinde yapı içerisine ilave edilen sodyum tungsten miktarındaki artış ile birlikte pik şiddeti daha keskin hale geldiği açıkça görülmektedir. 80 g/L'de (111)'de oluşan Ni pikinden sonra yaklaşık 53 oluşan pik hem amorf hem de kristal yapının bir arada olduğunu ifade etmektedir (Tian et al, 2021). Literatürde üçlü Ni-W-P kaplamadaki kristallik veya amorfluğun esas olarak fosfor miktarına bağlı olduğunu bildirmiştir (Balaraju et al, 2010;Keong et al, 2004).…”

YSZ/Ni double‐shell powder via surface electroless deposition tuned by an active kinetic model

“…The influence of external environmental factors on ceramic surface metallization kinetics via EN deposition has been extensively investigated. Researchers found that the deposition rate increased and decreased with increasing concentrations of nickel sulfate, sodium hypophosphite, pH, and bath temperature 23–25 . However, Yunacti et al 26 .…”

“…Researchers found that the deposition rate increased and decreased with increasing concentrations of nickel sulfate, sodium hypophosphite, pH, and bath temperature. [23][24][25] However, Yunacti et al 26 found that during processing, the plating rate increased with decreasing reducing agent concentration. To understand the intrinsic relationship between the deposition rate during process and the duration, researches [27][28][29] showed that electroless plating consists of different stages with various deposition rates.…”