Micro-Electrochemical Aspects of the Effects of Temperature on Pit Initiation at MnS Inclusion in Type 304 Stainless Steel
Micro-Electrochemical Aspects of the Effects of Temperature on Pit Initiation at MnS Inclusion in Type 304 Stainless Steel
复制标题
温度对 304 型不锈钢中 MnS 夹杂物点蚀萌生影响的微电化学方面
DOI：
10.1149/1945-7111/ac9d6c
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发表时间：
2022
影响因子：
3.9
通讯作者：
Sugawara Yu
中科院分区：
文献类型：
--
作者：
Takayama Riku;Nishimoto Masashi;Muto Izumi;Sugawara Yu
在1 M NaCl溶液中，从25 ℃到75 ℃，随温度的升高，304不锈钢的点蚀电位降低。MnS在0.1MNa2SO4中的溶解电位也随温度的升高而降低.由于在所有温度下的宏观点蚀电位在MnS的溶解电位范围内，MnS溶解电位的降低是确定高温下点蚀电位降低的关键。然而，在1 M NaCl中，微观点蚀电位超过了宏观点蚀电位：在25和50 C下在MnS和钢基体的边界处产生点蚀，但在75 C下，点蚀发生在MnS夹杂物的更深部分。闭塞的几何形状的形成是必不可少的点蚀;然而，由于溶解速率和潜在的MnS随温度而变化，闭塞的几何形状和位置的夹杂物，以及预计随温度而变化。304型不锈钢在1 M NaCl-10 mM Na 2S 2 O3中的去钝化pH在25 ℃至75 ℃的温度下从2增加到约3。溶解的MnS物种出现显着影响点蚀电位的降低。
In 1 M NaCl, the pitting potentials of resulfurized Type 304 stainless steel decreased as the temperature increased from 25 C to 75 C. The dissolution potential of MnS in 0.1 M Na 2 SO 4 also decreased with increase in temperature. As the macroscale pitting potentials at all temperatures ranged within the dissolution potential range of MnS, the decrease in MnS dissolution potential was critical in determining the decrease in pitting potentials at high temperatures. However, in 1 M NaCl, the microscale pitting potentials exceeded those of the macroscale pitting: pits were generated at the boundaries of the MnS and steel matrix at 25 and 50 C, but at 75 C, pitting occurred in a deeper portion of the MnS inclusion. The formation of an occluded geometry is essential for pitting; however, because the dissolution rate and potential of MnS vary with temperature, the shape and location of the occluded geometry at inclusions as well are expected to vary with temperature. The depassivation pH of Type 304 stainless steel in 1 M NaCl–10 mM Na 2 S 2 O 3 increased from 2 to approximately 3 at temperatures from 25 C to 75 C. The dissolved MnS species appeared to significantly influence the decrease in pitting potential.