Figure 3: Tooling concept developed for this project: combination of insulating shields and conforming anodes (addition to the main anodes)
要解決這些問題不能單純地只靠改變電鍍參數
（例如電鍍時間）：電鍍層過厚（紅色區域）和電鍍層較薄（藍色區域），即使是不同尺寸大小的產品，問題同樣存在。從圖2的柱狀圖中我們可以看到產品需要電鍍面區域、不同膜厚分布占的百分比，以及鋅鎳合金鍍層中鎳金屬的含量（紅色—超出標準區域，綠色—在標準範圍之內）。電鍍鎘或者電鍍鋅鎳合金工藝中產生的電鍍層過厚或過薄的比例其實是可以通過使用相同結構的輔助工具來優化並控制的。也就是說，之前用於電鍍鎘的電鍍輔助工具也可以在電鍍鋅鎳合金工藝中使用。這個項目是要設計一些合適的輔助工具，它在飛機起落架部件電鍍鎘和電鍍鋅鎳合金工藝過程中均可使用。這些電鍍輔助工具的設計與優化是通過電腦仿真技術來達到的。在這種電腦輔助設計的優化下， 我們有幾重目標：滿足膜厚要求（鎘：最少=10μm， 最大=25 μm），儘可能地優化總的電鍍時間，儘可能地讓電鍍輔助工具更加簡單、實用。這都可以通過一種基於電腦模擬膜厚的技術實現，即Elysc a PlatingManager 電鍍仿真軟件。這些輔助工具主要是依賴兩組活性部件：一，用於縮小產品膜厚過厚區域的絕緣屏蔽體，二，根據產品的實際情況而設計的輔助象形陽極（除了主要陽極之外的）（圖3）。同樣的電鍍輔助工具也可用在電鍍鋅鎳合金工藝中（鋅鎳合金膜厚標準：最少=7μm, 最大=15μm）。在這種情況下，合金中鎳金屬的含量需要嚴格控制，因為電鍍鋅鎳合金是一種異常共沉積現象。在電鍍輔助工具的幫助下，鋅鎳合金鍍層的膜厚和鎳含量（12~15%） 都會控制在給定範圍之內是如果鎳金屬含量超出規定範圍，這時我們要考慮電鍍鋅鎳合金的工藝參數的變化，也要考慮輔助工具相對與之前電鍍鎘時的一些區別，並加以優化。以上這些通過使用Elsyca PlatingManager電鍍仿真軟件可以快速實現。
electrodeposition parameters (e.g. plating time): the overplated (red) and underplated (blue) areas, even if in different dimensions, will still exist within the part. The bar graphs presented in Figure 2, indicate the percentage of the active surface area of the part that is contained in different layer thickness intervals, or Ni content intervals in case of Zn- Ni plating (red – out of specs, green – within the specs).
The percentage of overplated and underplated surfaces areas as resulting from both the Cd and Zn-Ni plating processes can be limited with a use of an identical tooling structure. This implies that existing tooling that was developed for the Cd plating process might be re-used for a replacement Zn-Ni plating process.
The project deals with the design of a conformal tooling structure that can be used for both Cd and Zn- Ni electroplating processes of a landing gear part. The conforming components are designed and optimized via computer simulation technology. This computer aided engineering approach of the conformal tooling structure has multiple targets: meeting layer thickness specifications (Cd: min = 10 μm, max = 25 μm), restrict the total plating time as much as possible and keep the tooling configuration as simple and robust as possible. The conforming tooling components were designed and optimised based on layer thickness computer simulations, using in-house developed Elsyca PlatingManager software technology. The tooling concept relies on two types of active tooling components: insulating shields for reducing the overplated areas of the part, and conforming pin anodes (in addition to the main anodes) which address the underplated zones (Figure 3).
The identical tooling system can be used for electroplating of the alternative Zn-Ni coatings (Zn-Ni specs:
min = 7 μm, max = 15 μm). In this case, the content of Ni needs to be controlled since the electrodeposition of Zn-Ni alloys has an anomalous behaviour. With the suggested tooling structure both the Zn-Ni layer thickness distribution and Ni content (0.12 – 0.15 w/w) are within given specifications. However, if the Ni content would be observed to be out of the specification range then either the process parameters of Zn- Ni electroplating need to be taken into account or the tooling configuration needs to be improved compared to the one used for Cd plating processes. This can easily be done using the Elsyca PlatingManager software.
參考文獻 References
[1]Characterization of a Zinc/Nickel plating bath, Paulo Vieira, Bart Van Den Bossche, Alan Rose, Plating&Surface Finishing, December 2009
[2]Elsyca PlatingManager:
http://www.elsycaplatingmanager.com/[3]www.elsyca.com /
info@elsyca.com
