Q345钢在抚顺地区土壤饱和溶液中的腐蚀行为

Corrosion Behavior of Q345 Steel in Five Saturated Soil Solutions in Fushun Region

用埋片和电化学方法研究Q345钢在抚顺市5个选定地区的土壤饱和溶液中腐蚀行为.结果表明,Q345钢在5种土壤饱和溶液中的腐蚀速率不同:腐蚀速率由大到小依次排列为李石区>露天矿区>望花区>东洲区>高尔山区,其中腐蚀最严重的是李石农田区,腐蚀速率为0.0564 mm/a,约为高尔山区的7倍;电化学实验表明,在东洲区和高尔山区土壤中Q345钢表面能够生成保护性的氧化膜,膜层稳定且致密均匀,对基材起到较好的保护作用,年腐蚀速率最低;在露天矿区和望花区土壤中Q345钢能够快速生成氧化膜,但氧化膜分布不均匀且疏松不致密,不稳定,对基材的保护作用较差;在李石区由于土壤的高含盐量和酸性促进吸氧阴极去极化,Q345钢腐蚀腐蚀最严重.

The corrosion behavior of Q345 steel in five typical soil saturated solutions in Fushun region was investigated by indoor buried corrosion test and electrochemical measurement technology in this paper. The results showed that the corrosion rate of Q345 steel in respective soils was ranked from big to small as an order of Lishi 〉Lutiankuang〉Wanghua〉Dongzhou〉 Gao＇ershan. The corrosion rate in Lishi soil was 0.0564mrn/a, which was the highest, and it was about seven times as large as that of Gao＇ershan soil. The electrochemical measurement results showed that compact and uniform oxide scales formed on Q345 steel in Dongzhou and Gao＇ershan soils, whcih prevented the steel from corrosion and expressed the lowest corrosion rate. In Lutiankuang and Wanghua soils, the corrosion products can form quickly, however, they were loose and porous, thus could not protect the steel from further corrosion. The Q345 steel corrosion rate in Lishi soil was the highest, because of the retative high salt content and acidity of the soil accelerated the depolarization of cathodic reaction.