摘要
为了取代剧毒氰化物多元浸锌工艺，开发了一种铝合金无氰四元合金浸锌液，研究了浸锌液中金属离子对浸锌过程稳定电位和置换层结晶形貌的影响，考察了镀层的附着性能。获得的优化工艺参数为：75g／LNaOH，16g／L ZnO，0.8g／L FeCl3，15g／LNiSO4，0．6g／L CuS04，40g／L EDTA，15g／L辅助配位剂（有机多元酸复配物），15g／L吡啶，1．2g／L稳定剂（高分子聚合物）；浸锌温度（20±2）℃。结果表明：随FeCl，含量降低，浸锌过程稳定电位正移，有利于结晶细化，其较好含量范围为0．4～0．8g／L；CuSO4含量变化对浸锌过程稳定电位影响不大，其含量增加有利于置换层结晶细化，较好的范围为0．6～0．8g／L；NiSO4含量在15～30g／L范围内对浸锌过程稳定电位影响不大。总体结晶效果都较好。一次和二次浸锌分别在30s及20s后电位变化趋于稳定；弯曲试验和热震试验表明镀层附着性能良好。
Cyanide-free solution for quaternary alloy zinc dipping of aluminum alloy was developed to substitute toxic cyanide complex solution for zinc dipping. The effect of metal ion on the stable potential in the dip plating process and the crystalline morphology and adhesive property of the replacement film were studied. The optimized composition of the solution for the zinc dipping was suggested as 75 g/L NaOH, 16 g/L ZnO, 0.8 g/L FeCl_3, 15 g/L NiSO_4, 0.6 g/L CuSO_4, 40 g/L EDTA, 15 g/L assistant complexing agent (organic polyacid complex), 15 g/L pyridine, and 1.2 g/L stablizer (polymer), and the temperature suggested as (20±2) ℃. The stable potential in the dip plating process assumed a positive shift with decreasing FeCl_3 content, which was beneficial to the refining of the crystalline, and the FeCl_3 content was suggested to be within 0.4~0.8 g/L. The amount of CuSO_4 had little effect on the stable potential in the dip plating process but the increase in the CuSO_4 content was beneficial to the refining of the replacement film crystalline, and the concentration of CuSO_4 was suggested to be 0.6~0.8 g/L. At a concentration of 15~30 g/L, NiSO_4 had little effect on the stable potential, while the potential assumed a stabilizing in 30 s and 20 s, respectively, for the first zinc dipping and the second zinc dipping. Moreover, the replacement film had good adhesion to the substrate.
出处
《材料保护》
CAS
CSCD
北大核心
2005年第8期26-28,41,共4页
Materials Protection
关键词
无氰浸锌
铝合金
稳定电位
金属离子
附着性能
cyanide-free zinc dipping
aluminum alloy
stable potential
metal ion
adhesion property
