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The behavior of Fe-12Cr-2Mo stainless steel exposed isothermally in tube furnace at 700°C for 10 h had been studied in different environments; of mixed environment (Ar-20%O2 with coated Na2SO4-50%NaCl salts), molten salt (Na2SO4-50%NaCl) and dry oxygen (Ar-20%O2) atmospheres. The exposed samples were characterized by using optical microscopy (OM), scanning electron microscope (SEM), energy dispersive X-ray (EDX) and X-ray diffraction (XRD). The results indicated that, sample exposed in mixed environments undergoes highest corrosion rate compared with other samples. The main phase exists in all samples generally were iron-rich oxides which non-protective and thick. Conversely, EDX analysis on cross-sectional samples revealed the Cr-enrichment developed underneath the iron-rich oxide scales as the chromium concentration increases towards near the substrate. In presence of salt mixture, the oxide scales undergo spallation, however there is no crack observed. The catastrophic corrosion sample was occurred in combined environment due to the oxidation induced by the chloridation and sulfidation phenomena as well.

SnO2 has been successfully grown on Si substrate using a thermal evaporation method, under different percentages of argon and oxygen gases. High purity Sn metal was used as reactants with deposition temperature were set at 900ºC. Different oxygen concentrations range between 1.6 and 10% were used during thermal evaporation process. The as-prepared metal oxides were analyzed using SEM-EDS, XRD and UV-VIS. SnO2 nanowhiskers were obtained at lower oxygen concentrations (1.6 to 6% oxygen), while nanowires structures were formed at higher oxygen percentages. XRD results revealed SnO2 produced were highly crystalline and no other impurity phase diffraction peaks were detected. EDS analysis revealed that only Sn and O elements were present in the sample which are consistent with XRD results. UV-VIS result revealed that the optical band gap energy of the metal oxides produced have low significant effect with increasing oxygen concentration. Optical band gap energy for was within 3.3 eV, which was lower than the optical band gap energy of bulk SnO2.

A plate of Fe-30Cr (wt%) were subjected to isothermal furnace at 600 °C in flowing CO2 gas at total pressure of approximately 1 atm. The reacted samples morphology and microstructure were characterized by using visual inspection, optical microscope, SEM and EDAX. The weight change measurement showed a fluctuating result during the exposure. The significant weight loss was observed after five hours exposure due to oxide scale exfoliation. Formation of different oxide and element presents on the interface of the specimen such as Cr2O3, C and Fe3C were revealed by X-ray diffraction and with supported by EDAX analysis. This behavior of the high temperature corrosion on Fe-30Cr was discussed based on morphology and microstructure observation.

In this paper, porous flower-like nickel oxide (NiO) on glass substrates were prepared by an aqueous chemical growth based technique. The morphology and optical observed were found to be influence by the reaction time. Field Emission Scanning Electron Microscopy (FESEM) revealed a porous flower-like structure growth on the substrates investigated. The optical band gap for NiO thin film calculated from transmission spectra has increased from 3.72 eV to 3.91 eV with the increasing of reaction time. This result shows that the growth time have some influence on morphology and optical of NiO films.