影響後超臨二氧化碳電鍍鎳之因子與機械性質之研究

The Effects of Process Parameters on the Mechanical Properties of Nickel Electroplated in a Post Supercritical CO2 Mixed Watts Bath

莊鴻緯(Hung-Wei Chuang)

指導教授 ： 李春潁

國立臺北科技大學/機電學院/製造科技研究所/碩士(2013年)

摘要

後超臨界二氧化碳電鍍製程，是希望混合超臨界二氧化碳之電鍍液在卸壓之後，可以利用二氧化碳從超臨界態回復到氣態時所形成之微小的氣泡附著再電鍍基材表面，使附著部分絕緣，接著氣泡很快的成長並且離開基材表面，這就如同超臨界電鍍製程中類似於脈衝電鍍的機制，使鍍層表面可以擁有更平整和更高的硬度。本實驗改變後超臨界之實驗因子如電流密度、鍍浴溫度、超臨界混合壓力、界面活性劑的添加，找出最佳實驗參數與鍍層機械性質之關係，實驗結果發現電流密度為50A/dm2、鍍浴溫度為50℃、混合壓力超過Sc-CO2臨界壓力(1072psi)，可以使鍍層晶粒大小降低、硬度提高至500HV以上而一般電鍍為300HV，但會產生較高的鍍層內應力300MPa左右而一般電鍍為180MPa，最後利用後超臨界二氧化碳之鍍液與一般電鍍之鍍液混合比例之實驗來驗證此電鍍新製程的實用化與產業利用的可行性。

關鍵字

超臨界電鍍 ； 電鍍鎳 ； 後超臨界電鍍

並列摘要

The post supercritical CO2 process utilizes the tiny CO2 bubbles remained in the bath after Sc-CO2 is relieved to atmospheric pressure to sweep over the substrate surface and isolate that local area. Then the bubbles serve as the media to cut off the local conduction of electric current, the mechanism is similar to pulse plating just like Supercritical CO2 process. Therefore, the deposited coating processes brighter surface and the higher hardness. The control parameters of the process, such as current density, temperature of the bath, mixing pressure of the Sc-CO2, surfactant added, were varied to find the best experiment parameters and the in influences on the mechanical properties. Experimental results showed that the with current density of 50A/dm2, plating bath temperature of 50 ℃, the pressure exceeding Sc-CO2 mixture critical pressure (1072psi), the coating could have refined grain size, 500HV hardness (conventional plating is 300HV). However, the coating had a higher internal stress of about 300MPa (conventional plating of 180MPa). Finally, electroplating in a bath with mixture of the post SC-CO2 and the conventional to verify this new electroplating process could have practicality and feasibility in the industrial electrolyte was successfully applications.

並列關鍵字

Supercritical CO2 Process ； Nickel Electroplated ； Post Supercritical CO2 Process

參考文獻

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