[PDF] Top 20 Mat. Res. vol.7 número1

... We deeply thank the guest editor, professor Fernando Rizzo, for setting up such interesting, updated thematic issue of Materials Research on High Temperature Corrosion in Energy Related [r] ... See full document

... slows the sulfidation rate below that expected if only H 2 S- H 2 were present. This is important because gases, which are thought to contain only H 2 S-H 2 often also contain some H 2 O, because of exposure to liquid ... See full document

... and CrH 2 O 4 which should evaporate from the specimen sur- faces. Still there is a difference in partial pressures of more than 3 orders of magnitudes between MoH 2 O 4 and CrH 2 O 4 . However since molybdenum is ... See full document

... From Fig. 6 it is clear that the corroded zone has a com- plete loss of Y and Al from the glass phase (some Al re- mains in Si 3 N 4 ). The concentration profile is thus akin to the schematic of Fig. 1. The nitrogen ... See full document

... of REs is directly at- tributable to reduction in chromium ion ...of REs is a result of the reduction in chromium ion movement along grain boundaries caused by the presence of barriers, in other words by ... See full document

... The fireside temperatures for superheater tubes that gen- erate this steam can be calculated from the heat flux through the tube wall: there are eight terms in the calculation, go- ing f[r] ... See full document

... The growth mechanisms that cause this change in micro- structure of the oxide scale between the different exposure techniques are not apparent: the differences in the activity Figure 2. [r] ... See full document

... Material Average Std. a) Schematic representation of a typical incremental erosion weight loss and 2D scar profile; b) Erosion rates of soda-lime glass, alumina, calcia-zircônica (CZ) an[r] ... See full document

... The internal surface was analyzed with the SEM, where a maximum surface layer of 15 µm was observed. EDS re- sults, shown in Fig. 3a, indicated the presence of iron (Fe), chromium (Cr), oxygen (O), phosphor (P) and ... See full document

... oxidation rate of the nano-crystal coatings is much lower than the coatings with the same composition but a larger grain size. A detailed study showed that the composition and microstruc[r] ... See full document

... Severe corrosion was observed for both samples exposed to the oxidizing atmosphere inside the regenerator at the temperatures of 650 °C and 700 °C. The formation of sev- eral iron oxides[r] ... See full document

... The samples subjected to lab-scale simulated conditions exhibited similar corrosion products as those obtained in the FCCU. Sulfur and oxygen were mainly observed within the Al-Fe-Cr coa[r] ... See full document

... Figures 7 and 8 show the main features of the micro- structure of the CaO partially stabilized zirconia coatings, which include voids with various shapes and dimensions, pores, lack of penetration of liquid ... See full document

... Main emphasis will be put on the growth and adherence of the oxide scales formed during exposure, their contact resistance at service temperature as well as their interaction with variou[r] ... See full document

... Another problem concerned with the doped ceria electrolyte is its decomposition by hydrogen gas dur- ing high temperature operation, generating Ce 2 O 3 , which imposes power losses to t[r] ... See full document

... Lanthanum chromite (LaCrO 3 ) is particularly an attrac- tive material as interconnect for solid oxide fuel cells (SOFCs) because of the good electronic conductivity in air, reasonable c[r] ... See full document

... Figure 6 shows graphitization in a steam pipe of DIN 15Mo3 alloy steel at the exit of a superheater at a nominal operating temperature of 480 °C. The tube suffered a local failure in the form of a “window” after some ... See full document

... Since very high crack- ing rates were observed during fixed-displacement loading of IN718, it is not very likely that grain boundary oxidation governs the grain-boundary-separation proce[r] ... See full document

... After cooling from reaction temperatures, alloys 1,5 and 7 retained their scales apparently intact, but the others sus- tained substantial degrees of scale loss. In situ analysis by X-ray diffraction (XRD) of the ... See full document

... The main points arising from the above analysis are summarised as follows: (i) fuel composition: on a mass com- parison basis, the critical contaminants species (S, Cl, alka- lis and tra[r] ... See full document