Unravelling corrosion degradation of aged aircraft components protected by chromate-based coatings

Despite extensive research, eliminating hexavalent chromium-based inhibitors from aerospace coatings remains challenging due to a lack of understanding of coating degradation during aircraft service. This study addresses the issue by investigating the protective mechanisms and aging processes of chromate-containing coatings on aircraft...

EDS microanalysis of blast furnace slag grains in aged concrete

The chemistry of ground granulated blast furnace slag (GGBFS) is one of the main factors affecting its reactivity. Knowing the composition of GGBFS used in aged concrete may help understand its past performance and estimate remaining service life. It is well known that GGBFS generally react slower than cement clinker. This thesis proposes that...

EDS Microanalysis of Unhydrated Blast Furnace Slag Grains in Field Concrete with Different Service Life

Because the essential quality metrics of blast furnace slag are based on its oxide composition, the determination of chemical compositions of unhydrated slag grains in an aged concrete could be useful for understanding its past performance and in predicting the remaining service life of existing slag-bearing concrete. In this research, the...

Corrosion of steel in cracked concrete: Chloride microanalysis and service life predictions

Reinforcement corrosion is frequently considered as the predominant degradation mechanism affecting reinforced concrete structures. Reinforced concrete structures are commonly subject to harsh environmental and loading conditions in which aggressive species can penetrate. Chlorides, present in seawater or de-icing salts, are the main responsible...

Unravelling the structural and chemical features influencing deformation-induced martensitic transformations in steels

A combination of Electron Back-Scattered Diffraction (EBSD) and high-sensitivity Electron Probe Micro-Analysis (EPMA) was used to correlate the changes in microstructural features upon deformation with local chemical composition in Transformation-Induced Plasticity steels. A novel cleaning procedure was developed that allows complete monitoring...

The Improvement of Oxidation Resistance of a Re-Based Diffusion Barrier/Ni–Al Coating on the Single-Crystal Ni-Based TMS-82+ Superalloy

Oxidation behavior of a Re-based diffusion barrier/Ni–Al coated single-crystal (SC) Ni-based TMS-82+ superalloy was studied to compare with those of the base and Ni–Al coated superalloys under cyclic air at 1150 °C for 200 h. The base superalloy showed a negative mass gain due to extensive oxide spallation, and the Ni–Al coated superalloy...

Improvement of the Oxidation Resistance of the Single-Crystal Ni-Based TMS-82+ Superalloy by Ni–Al Coatings with/without the Diffusion Barrier

Oxidation behavior of the uncoated base, Ni–Al coated and Re–Cr-Ni plus Ni–Al coated single-crystal (SC) Ni-based TMS-82+ superalloy is studied under cyclic air at 900ºC for 200 h to assess the oxidation resistance. Regardless of the coating processing, Ni–Al coating is effective in improving the oxidation resistance due to the formation of a...