摘要
为了获得耐蚀性比化学镀Ni-P合金更加优异的Ni-W-P三元合金镀层,在实验室条件下,通过正交试验研究了镀液中硫酸镍、钨酸钠、次亚磷酸钠、乳酸和添加剂浓度对镀层沉积速度和镀层在60℃、5%(质量分数)硫酸溶液中腐蚀速率的影响,获得了较佳的工艺参数:20～25g/LNiSO4.6H2O,30g/LNa2WO4.2H2O,27～30g/LNaH2PO2.H2O,100g/LNa3C6H5O7,15mL/L乳酸,30mg/L添加剂。通过对Tafel曲线的比较,证明本工作所得到的Ni-W-P镀层耐蚀性能高于非晶态Ni-P镀层,EDS图谱表明镀层中P的质量分数为14.00%,而W为3.69%。化学镀Ni-W-P工艺在耐腐蚀空冷器制备上获得了成功应用。
Orthogonal test was employed to prepare electroless Ni-W-P coating with better corrosion-resistance than electroless Ni-P alloy coating.Thus the optimized parameters for the preparation of the electroless Ni-W-P coating were established.The effects of the concentrations of various bath ingredients and additives on the deposition rate and corrosion rate of the Ni-W-P coating in 5% sulfuric acid solution at 60 ℃ were investigated.The corrosion resistance of the coating was examined based on measurement of Tafel curves via electrochemical route.Besides,the elemental composition of the coating was determined by means of energy dispersive spectroscopy.It was found that the Ni-W-P coating had much better corrosion resistance than amorphous Ni-P coating.The content of P and W in the coating was 14.00%and 3.69%(mass fraction),respectively.The corresponding optimized process for the preparation of electroless Ni-W-P coating had been successfully used for the corrosion protection of an air-cooler.
出处
《材料保护》
CAS
CSCD
北大核心
2007年第7期36-39,共4页
Materials Protection
