Anomalous Electrodeposition of Alloys

合金的反常电沉积

• 批准号: 9208596
• 负责人: Jan Talbot
• 金额: $ 12.48万
• 依托单位: University of California-San Diego
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-09-01 至 1995-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9208596&HistoricalAwards=false
• 关键词: Anomalous; Electrodeposition; Alloys

Anomalous deposition of alloys is defined by the less noble metal depositing preferentially to the more noble metal under certain conditions. This project aims to understand the mechanism of anomalous codeposition in plating processes using experiments and mathematical modelling. Previous work on the codeposition of nickel-iron suggests that change transfer in the monohydroxide species causes the anomaly; this work ascertains whether or not this mechanism can be extended to explain anomalous codeposition of the mutual alloys of nickel iron, cobalt, and zinc. The effect of buffering the pH of the plating bath is also investigated. Mathematical modelling consists of two parts: equilibrium calculations and one- dimensional diffusion modelling which includes the effects of buffering and of hydrolysis reactions. This phenomenon is most commonly encountered with the mutual alloys of iron, cobalt, nickel, and zinc. These alloys are widely used in electroplated films because of their high strength, hardness, and magnetic properties. Electrodeposited zinc-nickel provides corrosion protection for steel; high-iron nickel-iron (such as Invar) is used where low thermal expansion is required including microwave guides. optics. laser housings, and printed circuit boards; ferromagnetic alloys such as cobalt-nickel, iron-cobalt, and nickel-iron are widely used in electronic and magnetic devices including computer memory, magnetic shielding, and magnetic recording heads.

合金的异常沉积是由较低的贵金属定义的。 金属优先于更贵的金属沉积， 一定条件 该项目旨在了解 电镀过程中异常共沉积的机理 实验和数学建模。 以前的工作 镍铁共沉积表明， 单氢氧化物物种导致异常;这项工作 确定此机制是否可以扩展到 解释镍互合金的异常共沉积 铁钴和锌 缓冲溶液pH的效果 还研究了镀液。 数学建模 由两部分组成：平衡计算和一个- 三维扩散模型，包括以下影响 缓冲和水解反应。 这种现象最常见于相互 铁、钴、镍和锌的合金。 这些合金 广泛用于电镀薄膜，因为它们的高 强度、硬度和磁性。 电沉积 锌镍合金为钢提供防腐蚀保护;高铁 镍铁合金（如因瓦合金）用于低热 需要包括微波波导的扩展。光学. 激光器外壳和印刷电路板;铁磁性 合金如钴-镍、铁-钴和镍铁， 广泛用于电子和磁性设备，包括 计算机存储器、磁屏蔽和磁记录 构造标准部件.