Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/9736
標題: 電解沉積氧化鋯對SUS 316L不銹鋼性質之改善
The Improvement of Electrolytic Deposition of ZrO2 Thin Film on
作者: 鄭達煌
Cheng, Ta Huang
關鍵字: electrolytic deposition;電解沉積;zirconia(ZrO2);SUS 316L stainless steel;preferred orientation;pitting potential;protection potential;氧化鋯(ZrO2);SUS 316L不銹鋼;擇優取向;孔蝕電位;保護電位
出版社: 材料工程學研究所
摘要: 
本研究以電化學定電位電解沉積的方法在硝酸氧化鋯 [ZrO(NO3)2]水
溶液中沉積氧化鋯(ZrO2)陶瓷薄膜於 SUS 316L 不銹鋼基材表面,實驗藉
由對電化學參數和燒結條件等作探討,以瞭解這些因素對薄膜性質及結構
的影響並找到改善基材性質的適當條件。 實驗發現陰極極化曲線中H+
濃度極化(2H++2e-→H2)所對應的電位附近為適當的沉積電位,沉積電位
較高時因易在試片表面生成氫氣泡而破壞鍍層結構或使沉積不均。濃度越
高時沉積速率越快,其缺點為薄膜均勻性差,相對溶液濃度較低時沉積速
率越慢,但其優點是薄膜均勻性較好且較緻密。沉積時間過長時,薄膜因
厚度大而使裂縫加大,適當的沉積時間則薄膜厚度適當而在乾燥過程中不
使薄膜產生明顯裂縫(crack)。 經由XRD及TEM分析顯示 : (A) 316L不
銹鋼上所沉積氧化鋯鍍層在溫度T7以下存在的單斜晶相(-1 1 1)面具有擇
優取向的現象,但T9時再度出現的單斜晶相並無擇優取向的現象發生。推
測發生擇優取向原因為晶相與基材間有界面間化學鍵結效應存在。(B) 在
溫度T1以上,低溫成長的單斜晶相存在區約在T7以下,在此區內,單斜晶
相將首先成核析出,之後將出現單斜晶與正方晶的兩相共存區,最後將完
全轉換為正方晶相。而在不同溫度下,晶相成核與轉換所需時間隨溫度升
高而減少。 由極化實驗結果顯示適當燒結條件(如T2-t4等)的覆膜試
片其孔蝕電位與保護電位較未處理試片提升很多,且在試片表面僅觀察到
少量小面積很淺的孔蝕現象。

In this research, SUS 316L stainless steel was
electrolytically deposited with zirconia (ZrO2) coating in an
aqueous solution of zirconyl nitrate [ZrO(NO3)2]. By controlling
electrochemical and sintering parameters, the characteristics of
the coating were investigated. Through cathodic polarization
experiments, it was found that the better potential of
deposition was in the diffusion limit current iL of H+
concentration polarization of the cathodic polarization curves.
At more negative potential, hydrogen bubbles were found on the
specimen surface. Also the deposition rate is increased with the
concentration of solution increased, but without good
uniformity. In addition, a much longer deposition time made Zr(
OH)4 gel film produce obvious crack after drying, but a proper
deposition time did not. The XRD and TEM analysis showed
that : (A) Preferred orientation of monoclinic (-1 1 1) plan of
the coating deposited on 316L stainless steel was found at T≦
T7. It is considered as the chemical bonds effect between
substrate and crystallized zirconia. (B) At T≦T7, a monoclinic
phase was detected at first, then a tetragonal phase appeared
and coexisted with a monoclinic phase, at last the tetragonal
phase completely replaced the monoclinic phase. At different
temperature, the time for phase formation and phase
transformation was decreased with the temperature increased.
Dynamic polarization tests in 0.6M NaCl showed that specimens
with properly sintered zirconia coating (such as T2-T4 and so
on) can improve corrosion resistance, which showed the higher
pitting potential (Epit) and protection potential (Eprot) than
the as-deposited specimen. Also, the pitting density is lower
and shallower.
URI: http://hdl.handle.net/11455/9736
Appears in Collections:材料科學與工程學系

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