... by establishing links to the oxide scale morphology for (i) above and the underlying microstructure for (ii) and (iii) above. High temperature oxidation ethylene cracking Ni-Cr superalloys water vapor alloying elements INTRODUCTION In the petrochemical industry, cracking furnaces that produces ethylene...

.... Foil Oxidation Water vapor Metal loss INTRODUCTION Decreased cost and enhanced electrical efficiency (currently < 35 %) of recuperated microturbines are essential for their widespread use as power generation systems [ 1 , 2 ]. To further increase efficiency, research has been conducted towards...

..., are made to these alloys. In dry air, the behavior of chromia- and alumina-forming alloys can be predictable. However, in several instances, high temperature applications contain a significant amount of water vapor, which can lead to adverse effects on the oxidation process. The effects of water vapor...

... attack, especially at 800°C. However, at 25 bar the attack was reduced at 800°C compared to the breakaway oxidation at 1 bar. For the addition of SO₂ at 800°C, a more protective oxide formed at 1 bar but a thick, duplex Fe-rich oxide formed at 25 bar. carbon dioxide water vapor...

...Table 2 Metal Recession Measurements of the Alloys Tested in 10 vol.% Water Vapor for 360 Days and Ranked by Average Metal Affected for Each Temperature 760°C Sheet Alloy Weight Change (mg/cm²) Metal Loss (μm/side) Ave. Metal Affected (μm/side) Max. Metal Affected (μm/side...

...For the test campaign in pure water vapor at 557°C, buckling of a part of the oxide scale has widely been observed regardless of the oxidation time ( Figure 5 ). The proportion of buckled surface onto the total surface (30 mm x 10 mm) on each face of oxidized samples has been measured as a function...

...) high C activities with and without water vapor at 1-16 bar (100-1600 kPa) for the chemical process industry. Oxidation rates for AFA were compared to conventional candidate alloys as well as other Fe- and Ni-base alumina-forming alloys. The reaction products on AFA steel have been characterized using...

...Abstract Reformer reactor materials work at high temperatures (1000°C) under oxidizing and water vapor containing atmospheres. They are severely degraded by oxidation and thermal stresses that occur due to the cyclic operating conditions. Diffusion coatings improve the high temperature corrosion...

... 475 500 air + 10% H₂O 2.24 50 450 500 Abstract High temperature oxidation of heat-resistant alloys is considerably accelerated in the presence of water vapor which can severely reduce the longevity of high temperature components. The purpose of this study was to assess and compare...

... for the inner nozzle and the outer tube casing was EN: G-NiCr28W (a Cr₂O₃ former). SEM/EDX analysis showed that Cr disappears from the steel in an alarming rate, most probably by water vapor enhanced evaporation. The protective Cr₂O₃ decomposes with catastrophic...

...(OH)₂ evaporation and internal oxidation. Both model and commercial aluminide coatings reduced the amount of attack. The reaction products and Al interdiffusion were evaluated. NiCr alloys high temperature oxidation water vapor aluminide coatings INTRODUCTION The use of higher operating...

... sizes. It could be concluded that the smaller grain size promoted the preferential diffusion of Cr toward the alloy surfaces and the Mo-Cr-rich phase also played a role as a Cr-supplier, contributing to the maintenance of the Cr-rich protective oxide scale. water vapor low oxygen partial pressure...

...Water vapor is encountered as a minor component in ambient air and in larger concentrations as a by-product of various industrial processes such as combustion. High concentrations of water vapor in elevated temperature environments can alter the oxidation process for many different metals. ¹...

... material shows that the coated region makes no contribution to the creep strength. The consumption of metal due to the exposure in water vapor of uncoated specimens is compensated by the growth of a load-bearing oxide scale. Pre-oxidation of the alloy in humid air also affects the alloy microstructure...

...) or pack cementation on representative ferritic (Fe-9Cr-1Mo) and austenitic (type 304L stainless steel) are being studied in air + 10% water vapor in the temperature range of 650-800°C. Unlike the uncoated alloys, which are severely attacked in this environment, the CVD aluminide coatings have not failed...

...MCrAlY aluminides thermal barrier coatings environmental barrier coatings superalloys ceramics hot corrosion water vapor coating processing interdiffusion alumina chromia INTRODUCTION Abstract High-temperature materials such as MCrAlY, aluminide, silicon-base environmental barrier...

... oxidation recuperators water vapor INTRODUCTION Austenitic stainless steels have been widely employed for high temperature service due to their combination of good creep and oxidation resistance relative to other ferrous alloys. In applications where high temperature strength is of primary concern...

... in a thermobalance, under cyclic and isothermal conditions. The results show that the oxidation behavior of S35315 in water vapor is characterized by a protective chromium rich oxide scale and no breakaway oxidation was observed for this steel. The mechanism of oxidation in an atmosphere containing water vapor...

... hot corrosion water vapor coating processing interdiffusion molten salts carbon effects gas turbines fuel contaminants alumina chromia INTRODUCTION High temperature coatings provide a protective oxide barrier from corrosive or highly oxidative environments that may degrade the substrate...

...The damaging effect of water vapor on austenitic stainless steels has led to the substitution of higher-alloy materials, such as the nickel-base superalloys, in applications where oxidation failure is a concern. Nickel-base alloys which contain low levels of iron appear to be generally immune...