Identification of the Initial Oxide Films on 18-8 Stainless Steel in High Temperature Water

Abstract Initial oxide film formed on 18–8 stainless steel in high temperature water at 300 C (572 F) for 1 hour was identical with corundum type crystals like (Cr, Fe)2O3 alone or its coexistence with α-Fe2O3. On the contrary, the oxide film produced by prolonged oxidation (24 hours) consisted mainly of the spinel type crystals containing nickel.

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Transient Photoelectrochemical Analysis of the Semiconductor Properties of Oxide Films on Alloys

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1015.513 ◽

2014 ◽

Vol 1015 ◽

pp. 513-516

Author(s):

Yu Tan ◽

Wan Wan Wang ◽

Sheng Han Zhang ◽

Ke Xin Liang

Keyword(s):

Stainless Steel ◽

High Temperature ◽

Oxide Film ◽

Oxide Films ◽

Analysis Method ◽

Stainless Steel 316L ◽

Minute Amount ◽

High Temperature Water ◽

Temperature Water ◽

Semiconductor Properties

A transient photoelectrochemical analysis method is improved to investigate the semiconductor properties of oxide films on stainless steel 316L oxidized in high-temperature water. A minute amount of ZnO was added to the high-temperature water environment to alter the semiconductor properties of the oxide film deposited on stainless steel 316L. Characteristic phases in the oxide were investigated using the improved photoelectrochemical analysis method, and the semiconductor properties of the oxide film on stainless steel 316L suggested the presence of an n-type semiconductor. The photoelectrochemical dephasing angle showed movement of the flat band potential in the negative direction after ZnO addition.

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Effects of Environmental Factors on the Electronic Properties of Interfacial Oxide Film on 304L Stainless Steel in High Temperature Pure Water

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.261-263.919 ◽

2004 ◽

Vol 261-263 ◽

pp. 919-924 ◽

Cited By ~ 1

Author(s):

Zhan Peng Lu ◽

Yo-ichi Takeda ◽

Tetsuo Shoji

Keyword(s):

Stainless Steel ◽

High Temperature ◽

Oxide Film ◽

Electronic Properties ◽

Pure Water ◽

Oxide Films ◽

304L Stainless Steel ◽

Film Properties ◽

High Temperature Water ◽

Temperature Water

The electronic properties of the interfacial oxide film formed on 304L stainless steel in high temperature water are investigated by contact electric resistance (CER) measurements. Tests are performed in pure water with a wide range of dissolved oxygen (DO) content at 200, 250, and 288°C. The electrochemical potential (ECP) moves in the noble direction and CER increases when increasing DO. Results show that DO content has a dominant effect on the electronic properties of oxide film. The change of oxide film properties can also be attributed to the variation of the electrochemical potential, which is directly affected by DO content. Critical potentials exist for the formation and reduction of oxide films in high temperature water. Multiple steps are found for the reduction of oxide films due to de-aeration in 200, 250, and 288°C water, implying the presence of multiple-layer interfacial oxide films. The film reduction process is relatively slower than the film formation process. Present results show that even in high purity water, a moderate change of DO content can result in different surface conditions. Dissolved hydrogen has a moderate effect on interfacial surface films in deaerated water. In-situ monitoring of the oxide film properties by CER technique provides information on the interfacial reactions that are related to the SCC behavior of materials in high temperature water environments.

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