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在实验室海水中使用恒电流极化模拟了70℃下海底淤泥中Zn-0.3Al-0.03Cd阳极的早期破坏。阳极暴露表面受到剧烈的晶间腐蚀和一定程度的溶解。在整块材料中观察到晶间腐蚀,但未发现溶解。在各种不同的环境中,未极化的合金显示了同类腐蚀,但它不可能在纯Zn中产生。未能找到铝在晶界上偏析或沉淀的证据。此外,经固溶处理以保证单相组织的试样在短期模拟试验中遭受日间腐蚀。本文断定早先提出的铝在晶界上沉淀继之以优先溶解的机理是不正确的。根据对断口形貌的分析和试验条件的影响的分析,提出这类破坏是由氢的渗透引起的。
The use of galvanostatic polarization in laboratory seawater simulates the early destruction of Zn-0.3Al-0.03Cd anodes in seafloor silt at 70 ° C. The exposed surface of the anode is subject to severe intergranular corrosion and to some degree of dissolution. Intergranular corrosion was observed in the monolith but no dissolution was found. In a variety of environments, unpolarized alloys show the same type of corrosion, but it can not be produced in pure Zn. Failed to find evidence of segregation or precipitation of aluminum on the grain boundaries. In addition, samples that have been solution treated to ensure single-phase microstructure experience daytime corrosion in short-term simulation tests. The paper concludes that the previously proposed mechanism of precipitation of aluminum on the grain boundaries followed by preferential dissolution is incorrect. According to the analysis of the fracture morphology and the influence of the test conditions, it is suggested that such damage is caused by the infiltration of hydrogen.