Thermal healing of defects in oxide scales on iron-chromium alloys

Technical Report · Sun Apr 01 04:00:00 EDT 1990

DOI:https://doi.org/10.2172/7126820· OSTI ID:7126820

Swisher, J H; Cho, W D; Qiu, W W

An investigation completed earlier on the thermal healing of defects in Wustite scales on iron was extended to study the same phenomena in several Fe--Cr alloys. Included were a series of commercial Fe--Cr--Mo alloys containing up to 9% Cr, the 9% Cr alloy electroplated with Cr, and an Fe--25Cr--6Al alloy. Three types of experiments were conducted to study lateral mass transport of oxide into flaws introduced to simulated damage to protective oxide layers caused by particle erosion. It was found that flaw healing by lateral mass transport in the alloys was much slower than in unalloyed iron, which is understandable because elements like Cr and Al improve general oxidation resistance by facilitating the formation of scales with low diffusion rates. Experiments with electroplated Cr coatings showed potentially beneficial effects with respect to both general oxidation and flaw healing behavior. Compared to unplated material, the oxidation rate was lower, and the FeO outer scale was more adherent. Also the Cr content of the oxide in healed flaws was higher than in the oxide adjacent to the flaws. 17 refs., 14 figs., 2 tabs.

• Research Organization: Southern Illinois Univ., Carbondale, IL (USA). Dept. of Mechanical Engineering and Energy Processes
• Sponsoring Organization: DOE/FE
• DOE Contract Number: FC22-89PC89904
• OSTI ID: 7126820
• Report Number(s): DOE/PC/89904-T13; ON: DE90011453
• Country of Publication: United States
• Language: English

Related Subjects

20 FOSSIL-FUELED POWER PLANTS
200104* -- Fossil-Fueled Power Plants-- Components
36 MATERIALS SCIENCE
360102 -- Metals & Alloys-- Structure & Phase Studies
360103 -- Metals & Alloys-- Mechanical Properties
360105 -- Metals & Alloys-- Corrosion & Erosion
ALLOYS
ALUMINIUM ADDITIONS
ALUMINIUM ALLOYS
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
BOILERS
CHALCOGENIDES
CHEMICAL REACTIONS
CHROMIUM ALLOYS
CHROMIUM BASE ALLOYS
CHROMIUM COMPOUNDS
CHROMIUM OXIDES
COATINGS
CRYSTAL STRUCTURE
DEFECTS
DIFFUSION
DOCUMENT TYPES
FOSSIL-FUEL POWER PLANTS
INDUSTRIAL PLANTS
IRON ALLOYS
IRON BASE ALLOYS
IRON COMPOUNDS
IRON OXIDES
MASS TRANSFER
METALLURGICAL EFFECTS
MICROSTRUCTURE
MOLYBDENUM ALLOYS
NICKEL ADDITIONS
NICKEL ALLOYS
OXIDATION
OXIDES
OXYGEN COMPOUNDS
PETROLEUM REFINERIES
POWER PLANTS
PROGRESS REPORT
SCALING
THERMAL POWER PLANTS
TRANSITION ELEMENT COMPOUNDS