化学镀镍低铬钝化无机添加剂的筛选  

Selection of inorganic additives for low-chromium passivation of electroless plated nickel coating

作　　者：曾庆雨[1] 刘定富[1] 毕晨[1] 杨明悦[1] 

机构地区：[1]贵州大学化学与化工学院,贵州贵阳550025

出　　处：《电镀与涂饰》2016年第9期465-469,共5页Electroplating & Finishing

基　　金：2013贵州省科技计划(黔科合GY字[2013]3035号)

摘　　要：在pH 2.0±0.1、温度(70±2)°C的条件下,采用5 g/L K_2CrO_3+0.5 g/L(NH_4)_2SiF_6低铬钝化液对45钢上化学镀Ni–P层钝化10 min。以钝化试样的耐硝酸变色时间为指标,通过单因素试验和正交试验对几种钝化液的无机添加剂进行筛选和优化,得到的最优组合为16 g/L钼酸铵+6 mg/L硝酸铈+8 mg/L氧化钇。采用最佳添加剂后,钝化膜表面平整、致密,耐硝酸变色时间为482 s,中性盐雾试验48 h的保护等级为9级,综合性能优良。The electroless plated Ni-P coating on 45 steel substrate was passivated using a low-chromium passivating solution composed of 5 g/L K2CrO3 and 0.5 g/L （NH4）2SiF6 at temperature 70 ± 2 ℃ and pH 2.0 ± 0.1 for 10 min. Several kinds of inorganic additives for passivating solution were selected and optimized through single factor experiment and orthogonal test using the discoloration time of passivation coating resistant to nitric acid as the evaluation indicator. The optimal formulation is 16 g/L ammonium molybdate ＋ 6 mg/L cerium nitrate ＋ 8 mg/L yttrium oxide. The passivation film obtained from the bath containing the optimized additive composition features a good performance, as shown by an even and compact surface, a discoloration time resistant to nitric acid of 482 s and a orotection zrade of 9 after neutral salt soray test for 48 h.

关 键 词：化学镀镍 低铬钝化 添加剂 钼酸铵 稀土 耐蚀性 

分 类 号：TQ153.12[化学工程—电化学工业] TG178[金属学及工艺—金属表面处理]