运用冷凝液循环蒸发方法模拟汽车消声器内部腐蚀环境,对比研究了在有/无缝隙条件下409型不锈钢在冷凝液中的腐蚀行为。结果表明:与无缝隙试样相比,有缝隙试样在循环试验过程中表现出相对较低的自腐蚀电位;20次循环试验后,腐蚀阻力较低,腐蚀深度较大;缝隙导致不锈钢局部腐蚀速率约增大2.4倍,这主要是由缝隙内部在蒸发过程中更容易保持电解液腐蚀环境、并不断酸化导致的。
The corrosion behavior of type 409 stainless steel with or without crevice was investigated in simulated condensate of automotive muffler by cyclic evaporation method. The results show that stainless steel samples with crevice have lower corrosion potential, lower corrosion resistance and bigger corrosion depth than those without crevice. The presence of crevice accelerates the localized corrosion rate of the stainless steel about 2. 4 times, which is due to the easy formation of electrolyte corrosion state and electrolyte acidification in the crevice.