船用907钢表面化学镀耐冲刷腐蚀型NiMoB合金层的工艺参数优化

为提高船用907钢的耐冲刷腐蚀性能,设计了一种可与船用907钢海水管路内壁表面形成稳定化合物的NiMoB合金镀层,并采用正交试验优选了该化学镀液中NiCl_2,EDTA,Na_2MoO_4,KBH_4的浓度。采用扫描电镜观察合金镀层形貌;采用阻抗谱、极化曲线分析了合金镀层在模拟海水中的耐蚀性,并在模拟海水冲刷腐蚀环境下分析了Ni Mo B镀层的抗冲刷腐蚀特性。结果表明:不同的镀液参数对Ni Mo B镀层的性能影响较大,当NiCl_245.0g/L、EDTA 9.0 g/L、Na_2MoO_415.0 g/L、KBH_40.8 g/L,乙二胺45.0 g/L,NaOH 90.0 g/L时,NiMoB非晶态薄膜表面呈胞状物陈列,具有致密的表面形貌,镀层的耐腐蚀、抗冲刷腐蚀性能优良。

Optimization of Process Parameters of NiMoB Alloy Electroless Plating Coating for Ship-Built 907 Steel

A stable compound NiMoB alloy coating on the inner surface of 907 steel sea-water pipeline was designed and the main components (NiCl2,EDTA,Na2MoO4 and KBH4) in the chemical bath were determined by orthogonal experiment.The coating morphology was observed by SEM and the corrosion resistance was evaluated by impedance and polarization curve.Besides,the erosion resistance of NiMoB filns was analyzed in simulated sea water erosion environment.Results showed that the different bath parameters greatly influenced the properties of NiMoB conversion layer.When NiCl2 content was 45.0 g/L,EDTA content 9.0 g/L,Na2MoO4 content 15.0 g/L,KBH4 content 0.8 g/L,ethanediamine content 45.0 g/L and NaOH content 90.0 g/L,the obtained NiMoB amorphous coating was arranged in cellular shape densely and the coating's corrosion resistance and erosion resistance were excellent.