碳鋼於0. 5M包含鋁離子與硫脲的氯化鈉水溶液中之交流阻抗研究

EIS of Carbon Steel in 0.5M NaCl Solution Containing Al3+ -Thiourea

本研究以交流阻抗方法探討添加劑存在與否，對碳鋼於0.5M氯化鈉水溶液中的影響。當環境溫度小於50℃時，添加硫脲與鋁離子於氯鹽環境中，均可抑制碳鋼的腐蝕；然而當溫度大於60℃時，反而會加速其腐蝕。在不同添加劑系統如：硫脲（T）、鋁離子（A）、鋁離子加硫脲（AT） 中，將討論溫度對極化阻抗值（Rp）與表面覆蓋率（θ）的影響，並提出腐蝕抑制和腐蝕加速之機理。

EIS of carbon steel in 0.5M NaCl solutions containing whether or not an additive was investigated. The addition of thiourea and aluminium sulphate into the chloride solution inhibits the steel corrosion at temperatures <50℃; however, it accelerates the corrosion at temperatures >60℃. The variation of polarization resistance (Rp) and surface coverage (θ) with temperatures in various systems containing additives such as thiourea (T), Al3+ (A), and Al3+ -thiourea (AT) is discussed. The mechanisms for corrosion inhibition and for corrosion acceleration are proposed.