Effects of sigma phase precipitation on seawater pitting of duplex stainless steel
Effects of sigma phase precipitation on seawater pitting of duplex stainless steel
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DOI：
10.1016/j.desal.2006.05.021
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发表时间：
2007-03
期刊：
影响因子：
9.9
通讯作者：
H. Ezuber;A. El-Houd;F. Elshawesh
中科院分区：
文献类型：
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作者：
H. Ezuber;A. El-Houd;F. Elshawesh
采用动电位极化法研究了SAF 2205和3RE 60双相不锈钢在人工海水中不同温度下的点蚀特性（25、50和80°C）和σ相沉淀（在845°C的预淬火热处理温度下进行10分钟、60分钟和300分钟的不同加热持续时间产生）。结果表明，2205 DSS型经轧制退火和σ相沉淀的样品在室温下不受点腐蚀，然而，该合金在50°C下表现出对点腐蚀的敏感性。随着试验温度的升高（至80°C）和/或不适当的热处理持续时间，导致点蚀的可能性降低（变得不那么高贵），并且随着长时间的热处理暴露变得更加有效。相比之下，轧制退火的3RE 60在环境温度下表现出海水点蚀攻击，并且点蚀攻击的强度随着测试温度或σ相沉淀体积的增加而增加。结果清楚地表明，氮和相对较高的铬含量在2205合金中的存在对于耐海水点蚀是有利的。
In this study the potentiodynamic polarization technique was employed to study the pitting corrosion characteristics of duplex stainless steel types SAF 2205 and 3RE60 duplex stainless steels in artificial seawater at various test temperatures (25, 50 and 80°C) and sigma phase precipitation (produced at pre-quenched heat treatment temperature of 845°C for different heating duration of 10, 60 and 300 minutes). The results showed that mill-annealed and sigma phase precipitated samples of type 2205 DSS were immune to pitting corrosion at ambient temperature, however, the alloy exhibited susceptibility to pitting attack at 50°C. The potential necessary to cause pitting corrosion decreased (became less noble) with increasing test temperature (to 80°C) and/or inappropriate heat treatment duration and become more effectual with long heat treatment exposure. In contrast, the mill-annealed 3RE60 exhibited seawater pitting attack at ambient temperature and the intensity of the pitting attack increased with increasing test temperature or sigma phase precipitation volume. The results clearly indicated that the presence of nitrogen and relatively higher chromium content in the 2205 alloy is an advantage for seawater pitting corrosion resistance.