(1. 太原理工大學(xué) 材料科學(xué)與工程學(xué)院，太原 030024；
2. 太原科技大學(xué) 材料科學(xué)與工程學(xué)院，太原 030024)
摘 要: 采用一步水熱法在AZ31鎂合金表面上制得CaAl-LDH膜層，采用X射線衍射儀(XRD)、掃描電子顯微鏡(SEM)、能譜儀(EDS)、電化學(xué)阻抗測試(EIS)、極化曲線等手段研究水熱反應(yīng)溫度對CaAl-LDH膜層形貌及性能的影響。結(jié)果表明：隨著水熱反應(yīng)溫度的升高，CaAl-LDH膜層的厚度隨之增加，膜層LDH結(jié)構(gòu)的尺寸增大，耐蝕性先增強后減弱；當(dāng)水熱反應(yīng)溫度為120 ℃時，CaAl-LDH膜層的表面最平整致密，層間陰離子為 的加載量最大，離子交換作用最強，膜層的耐蝕性最佳。此時，膜層的電荷轉(zhuǎn)移電阻Rct為9.933×106 Ω?cm2，腐蝕電流密度Jcorr為8.0×10?9 A/cm2。CaAl-LDH膜層的生長模式符合典型的Stranski-Krastanov生長模型。反應(yīng)溫度會影響LDH的結(jié)晶速度和生長過程，進(jìn)而影響了CaAl-LDH膜層的結(jié)構(gòu)和性能。在120 ℃下水熱制備CaAl-LDH膜層是提高AZ31鎂合金耐蝕性的有效方法。
關(guān)鍵字: AZ31鎂合金；水熱法；CaAl-LDH；耐蝕性；溫度
（1. College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, China;
2. College of Materials Science and Engineering, Taiyuan University of Science and Technology, Taiyuan 030024, China）
Abstract:A one-step hydrothermal method was used to prepare a CaAl-LDH film on the AZ31 magnesium alloy. X-ray diffractometer (XRD), scanning electron microscope (SEM), energy spectrometer (EDS), electrochemical impedance test (EIS) and polarization curve were used to study the effects of the hydrothermal reaction temperature on the morphology, chemical composition and corrosion resistance of the CaAl-LDH film. The results show that as the hydrothermal reaction temperature increases, the thickness and density of the CaAl-LDH film increase, the sheet size increases, and the corrosion resistance increases first and then decreases. When the hydrothermal reaction temperature is 120 ℃, the surface of the CaAl-LDH film is the most flat and dense, and the loading of anion between layers is the largest, which indicates that the LDH film has the strongest ion exchange effect. So the corrosion resistance of the CaAl-LDH film prepared at 120 ℃ is the best, which charge transfer resistance Rct is 9.933×106 Ω·cm2, corrosion current density Jcorr is 8.0×10-9 A/cm2. The growth mode of CaAl-LDH film conforms to the typical Stranski-Krastanov growth model. The reaction temperature will affect the crystallization speed and growth process of LDH, which in turn affects the structure and performance of CaAl-LDH film. Hydrothermal preparation of CaAl-LDH film at 120 ℃ is an effective method to improve the corrosion resistance of AZ31 magnesium alloy.
Key words: AZ31 magnesium alloy; hydrothermal method; CaAl-LDH; corrosion resistance; temperature
