镍铝青铜(NAB)的微观组织及腐蚀性能

Microstructure and Corrosion Properties of Nickel Aluminum Bronze (NAB)

以目前国内外常用的船用镍铝青铜试样(国产支架S1、进口舵叶S2、进口螺旋桨S3)为研究对象,通过OM、SEM、失重法和电化学工作站等研究其微观组织、第二相组成和耐蚀性,结果表明:S1、S2和S3的微观组织主要由α、κ(κ_(Ⅱ)、κ_(Ⅲ)、κ_(Ⅳ))相组成,其中κ_(Ⅱ)、κ_(Ⅲ)为富Ni相。在3.5%NaCl溶液中,S1试样的腐蚀速率最高,S3的腐蚀速率最低。界面电荷转移电阻是影响腐蚀过程的主要因素,S3的界面电荷转移电阻最大(3 098Ω),且其表面腐蚀产物主要由Al_(2)O_(3),Cu_(2)Cl(OH)_(2)和(CuNi)_(2)Cl(OH)_(3)组成。

Taking the commonly used marine nickel-aluminum-bronze materials at home and abroad(domestic bracket S1, imported rudder blade S2, imported propeller S3) as the research object, and the microstructure, second phase composition and corrosion resistance of these samples were studied by OM, SEM, weight loss method and electrochemical workstation. The results showed that the microstructures of S1, S2 and S3 were mainly composed of α and κ(κ_(Ⅱ),κ_(Ⅲ),κ_(Ⅳ)) phases, among which κ_(Ⅱ) and κ_(Ⅲ) were Ni-rich phases. In 3.5%NaCl solution, the corrosion rate of S1 sample was the highest, and the corrosion rate of S3 was the lowest. The interface charge transfer resistance was the main factor affecting the corrosion process. The interface charge transfer resistance of S3 were the largest(3 098 Ω), and its surface corrosion products were mainly composed of Al_(2)O_(3),Cu_(2)Cl(OH)_(2) and (CuNi)_(2)Cl(OH)_(3)