不同脉冲电沉积电流密度制备的Ni-W合金镀层在固-液两相流硫酸溶液中的冲刷腐蚀

Erosion Resistance of Ni-W Alloy Coatings Prepared Under Various Pulse Current Densities in Solid-Liquid Two-Phase Sulfuric Acid Solution

为了探究Ni-W合金镀层对材料表面冲刷腐蚀的影响,在不同电流密度下采用电沉积法在20R钢表面制备了Ni-W合金镀层,采用失重试验、固-液两相流冲刷腐蚀试验并结合X射线衍射(XRD)、电化学测试等方法研究Ni-W合金镀层在10%H_2SO_4中静态浸泡与在固-液两相流(10%H_2SO_4+SiO_2)中的冲蚀腐蚀行为。结果表明:Ni-W合金镀层具有良好的耐蚀性,20R在10%H_2SO_4中的静态腐蚀速率是电流密度5 A/dm^2制得的Ni-W合金镀层的4.6倍,20R的冲刷腐蚀速率是电流密度5 A/dm^2制得的Ni-W合金镀层的2.0倍。Ni-W合金镀层的冲蚀机制以腐蚀为主。

In order to explore the effect of Ni-W alloy coating on erosion and corrosion of material surface, the Ni-W alloy coatings on 20R sur- face were prepared under various current densities by electrodeposition. The corrosion （ 10% H2 SO4 ） behavior and two - phase flow erosion （ 10% H2SO4,＋ SiO2 ） behavior of the coatings were studied by weight-loss method, solid-liquid two-phase sulfuric acid solution erosion test and X-ray diffractometer as well as electrochemical tests. Results showed that Ni- W alloy coatings had good corrosion resistance. The static corrosion rate of 20R was about 4.6 times as great as that of Ni-W alloy plates prepared under 5 A/dm2, and the two-phase flow erosion rate of 20R was 2.0 times as great as that of Ni-W alloy coating prepared under 5 A/dm2. Besides, the erosion mechanism of Ni-W alloy coating was dominated by corrosion.