Corrosion and erosion–corrosion behaviour of activated combustion high-velocity air fuel sprayed Fe-based amorphous coatings in chloride-containing solutions
Abstract Corrosion and erosion–corrosion (E–C) behaviour of the AC-HVAF sprayed FeCrMoMnWBCSi amorphous metallic coating (AMC) were investigated. Compared with the HVOF AMC, the AC-HVAF AMC presents relatively denser structure with lower porosity and almost nonexistent oxides, which holds higher ability to resist uniform corrosion and pitting owing to the impact structure and the low donor density in the passive film. The enhanced E–C resistance of AC-HVAF AMC could be related to the high hardness and compact structure resulting in the low erosion and synergy weight loss.
Abstract Many human operations have created a large population of small orbital debris in near Earth environment. The threat they represent for satellites is a major factor for the preparation of future space missions. Several experiments devoted to the study of this environment, as well as various materials exposed to space, have been retrieved in the past few years. The analysis of the results shows some differences with previous modeling. Comparison with data from LDEF and from EURECA give some insight in the long term evolution of particle size distribution. Chemical identification of particle remnants inside craters is difficult but provides valuable information on the origin of the impactors. Permanent monitoring of environment is obviously needed, especially for the type of orbits where data are presently scarce ie. heliosynchronous and geostationary orbits.