Thermal high-temperature corrosion

Tips of platinum, platinum—nickel alloy, or iridium can be resistance-welded to spark-plug electrodes for improved reHabiHty and increased lifetime. These electrodes are exposed to extremely hostile environments involving spark erosion, high temperature corrosion, thermal shock, and thermal fatigue. 

At very high and very low temperatures, material selection becomes an important design issue. At low temperatures, the material must have sufficient toughness to preclude transition of the tank material to a brittle state. At high temperatures, corrosion is accelerated, and thermal expansion and thermal stresses of the material occur. 

Lee SH, Themelis NJ and Castaldi Ml, High-Temperature Corrosion in Waste-to-Energy Boilers. J Thermal... 

The integrity of the floor liner in the case of thermal expansion of its total area was confirmed at the Monju design stage however, an examination of its integrity in the case of localized temperature rises during medium-scale and small-scale leaks will now also be performed. Further work is requited on damage due to high temperature corrosion by combustion residues. 

Because of the high temperature corrosion resistance and thermal stability exhibited by magnesium-chromium oxide refractories in copper smelting, converting and fire refining furnaces, little research has been conducted on other refractory families. However, the concern for hexavalent chromium (Cr ) as a potentially hazardous waste in spent refractories from copper production furnaces has prompted the recognition that a more environmentally acceptable material is needed for the copper industry. 

Effects of Thermal Cycling on High-Temperature Corrosion. 209... 

If an alloy is to have acceptable resistance against high-temperature corrosion, it must react with the environment to form a continuous and adherent slow-growing scale which has sufficient mechanical properties to withstand the effects of both growth and thermal stresses. As discussed in Chapter 3 of this volume, ideal protective scale growth obeys diffusion-controlled, parabolic kinetics, i.e. ... 

F. Monteverde The thermal stability in air of hot-pressed diboride matrix composites for uses at ultra-high temperatures. Corrosion Science 47,2020-2033 (2005). 

S.T. Bluni and A.R. Marder, Effects of Thermal Spray Coating Composition and Microstructure on Coating Response and Substrate Protection at High Temperatures, Corrosion, Vol 52,1996, p 213... 

ISO document ISO/TC 156 NWIP Corrosion of Metals and AUoys-Test Method for Thermal Cycling Exposure Testing under High Temperature Corrosion Condition for Metalic Materials this document is based on the results of the COTEST project)... 

In the present study the characterization of the effect of specimen geometry and the effect of exposure under thermal cycling conditions on the oxide scale failure mechanisms were the main objectives. Kinetics of corrosion product formation as well as changes in the chemical composition of both spalled oxide scale segments and internal corrosion products were determined to evaluate the material s resistance to high-temperature corrosion attack. 

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