SUS441表面鍍覆錳鈷氧化物保護膜之微結構及電化學特性

A Study on the Microstructural and Electrochemical Properties of SUS441 Manganese Cobalt Oxide Coating Films

曾惠萍(H.P. Tseng) ； 雍敦元(T.Y. Yung) ； 楊朋(Peng Yang) ； 劉建國(C.K. Liu) ； 李瑞益(R.Y. Lee)

《鑛冶：中國鑛冶工程學會會刊》 61卷3期 (2017/09) Pp. 96-102

https://doi.org/10.30069/MM.201709_61(3).0010

摘要

本研究於商用之肥粒鐵系SUS441 不銹鋼基板表面，以脈衝直流磁控濺鍍方式分別鍍覆1.5 μm 及3.5 μm 之錳鈷氧化物(Mn, Co)_3O_4(MCO) 保護膜， 經800 ℃，1800 小時2 LPM空氣下熱處理後，探討其保護膜層及基板氧化層組成、微結構與電化學阻抗之關係，並比較不同預氧化條件（800℃，25 小時及850℃，25 小時）處理後，鍍覆3.5 μm 之MCO 保護層對電性之影響。試樣經800℃熱處理1800 小時後，量測室溫下之電化學阻抗頻譜(EIS) 及高溫面積比電阻(ASR)，建立等效電路模型模擬各膜層之阻抗並與XRD、SEM/EDS 之分析觀察比較，透過數值模擬了解各氧化層間之電性關係，並提出反應機制。研究結果顯示，鍍覆MCO 能有效抑制鉻元素擴散，提高導電效率，經800℃空氣下1800 小時之熱處理，MCO 與基板氧化層形成一穩定且擁有較佳電性之(Mn, Co, Cr)_3O_4 層，且於MCO 鍍膜厚度為3.5 μm 之試樣，擁有最佳之電性。

關鍵字

脈衝直流磁控濺鍍 ； 錳鈷氧化物 ； 電化學阻抗頻譜 ； 等效電路模擬 ； 高溫面積比電阻

並列摘要

We investigated the microstructural and electrochemical properties of (Mn, Co)_3O_4 (MCO) protective films coated on SUS441. SUS441 were pre-oxidized in an ambient atmosphere at 800°C and 850°C for 25 hours, respectively. The thickness of MCO films were 1.5 and 3.5 μm then deposited on the surface of SUS441 by using pulsed DC magnetron sputtering technique. The as-coated specimens aged at 800°C for 1800 hours in an air atmosphere with a flow rate of 2 LPM. After aging, the crystalline phases, microstructures, and electrochemical resistances of MCO coated SUS441 were examined by using XRD, SEM/EDS, electrochemical impedance spectroscopy (EIS), and Area Specific Resistance (ASR). A proper equivalent circuit model was used to interpret the results of EIS. The pre-oxidized specimen of SUS441 with a 3.5 μm MCO coating had the best electrochemical Properties.

並列關鍵字

Pulsed DC magnetron sputtering ； Manganese-cobalt oxide ； Electrochemical Impedance Spectrum ； Equivalent circuit model ； Area Specific Resistance

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