T700碳纤维复合材料与30CrMnSiA高强钢在NaCl溶液中的电偶腐蚀行为

Galvanic Corrosion Behavior of Carbon Fiber Epoxy Resin Composite and High Strength Steel in Sodium Chloride Solution

为了探究碳纤维复合材料与高强钢在相互接触时实际使用的可行性,将T700碳纤维环氧树脂复合材料与30CrMnSiA高强钢置于NaCl溶液中进行电偶腐蚀,研究了温度、NaCl浓度、pH值对二者电偶腐蚀行为的影响。采用电化学法测试了二者在3.5%NaCl溶液中的开位电位,采用扫描电镜观察二者电偶腐蚀前后的形貌。结果表明:碳纤维与高强钢在NaCl溶液中接触时会发生严重的电偶腐蚀;温度、NaCl浓度及pH值对电偶电流有较大的影响;高强钢电偶腐蚀后,表面有一层暗红色的铁锈,腐蚀严重;随着腐蚀的进行,碳纤维环氧复合材料表面树脂由于溶胀作用遭到剥离,碳纤维露出得越来越多,进一步加快了高强钢的腐蚀。

T700 carbon fiber epoxy resin composite and 30CrMnSiA high strength steel were coupled in NaCl solution to undergo galvanic corrosion so as to explore the feasibility to use them in contact. The effects of temperature and concentration as well as pH value of NaCl solution on the galvanic corrosion behavior of the kinds of materials were investigated. The open-circuit potential of the composite and high strength steel in 3. 5% NaCl solution was determined with an electrochemical workstation,while their morphologies before and after galvanic corrosion were observed with a scanning electron microscope. Results showed that carbon fiber epoxy resin composite and the high strength steel experienced severe galvanic corrosion when they were coupled in the saline solution,while temperature and the concentration and pH value of NaCl solution had significant effects on their galvanic corrosion behavior. Namely,the high strength steel coupled with carbon fiber epoxy composite in NaCl solution experienced severe galvanic corrosion forming deep-red rust on the surface. Besides,along with extending time of corrosion,the carbon fiber epoxy resin composite was peeled off owing to swelling effect,thereby leading to enhanced exposure of the carbon fiber and accelerating the corrosion of the high strength steel.