2024Al与SiC_p/2024Al复合材料的腐蚀与腐蚀控制研究

CORROSION RESISTANCE AND PROTECTION EFFICIENCY OF 2024Al AND SiC_p/2024Al METAL MATRIX COMPOSITE

用电化学方法和腐蚀失重法研究了 ２０２４Ａｌ和ＳｉＣｐ／２０２４Ａｌ复合材料在 ３．５％ＮａＣｌ水溶液中的耐蚀性，用电化学阻 抗技术对它们的硫酸阳极氧化膜保护性进行了跟踪评价．结果表明ＳｉＣｐ／２０２４Ａｌ在 ３．５％ＮａＣｌ水溶液中比 ２０２４Ａｌ有较大的 腐蚀敏感性．２０２４Ａｌ表面的阳极氧化膜，经热水封闭后，可提供相当好的保护作用．热水封闭的Ｓｉｐ／２０２４Ａｌ阳极氧化膜， 具有良好的耐 ＮａＣｌ溶液腐蚀能力，由于氧化膜中ＳｉＣ颗粒的存在破坏了氧化膜的完整性和均匀性，故其耐蚀性不如 ２０２４ Ａｌ 合金的阳极氧化膜．

The corrosion resistance of 2024 Al and SiCp/2024Al composite in 3.5% NaCl aqueous solution were investigated with electrochemical method and immersion test, The corrosion protection of sulfuric acid anodized coatings on these materials was monitored by electrochemical impedance spectroscopy. The results show that the SiCp/2024Al composite is more susceptible to corrosion than its matrix alloy in 3.5% NaCl solution. For 2024Al, the anodized coating sealed in hot water provides excellent corrosion protection to 3.5% NaCl solution. The anodized coating on the SiCp/2024Al provides satisfactory corrosion protection, but it is not as effective as for 2024Al because the structure of the anodized layer is affected by Sic particulates.