A trial of quantitative estimation of Al-corrosion detected by neutron radiography.
Comparing the hydrogen content in aluminum hydroxides, one of the main components of Al-corrosion, with that in polyethylene sheets, corroded degree of practical Al-corrosions were estimated quantitatively by neutron radiography.
Neutron Radiography of Aluminium Alloy Corrosion Damage
The potential for neutron radiography to detect hydrogenous corrosion products in aircraft structures was examined using a series of naturally and artificially corroded aluminium alloy samples. The sensitivity of this technique for detecting corrosion damage was intially assessed using the Moata reactor facility and commercial neutron radiography services. Neutron radiographs of the corroded samples were obtained using a portable accelerator and a californium-252 isotope source. Reactor, accelerator and isotope neutron radiographs have been compared to assess the sensitivity of portable neutron sources.
The role of dissolved oxygen in supercritical water in the oxidation of ferritic–martensitic steel
Abstract To assess the role of dissolved oxygen in supercritical water on the growth processes of oxide scales, a marker experiment of ferritic–martensitic steel was performed by exposing to supercritical water (H 2 16 O) containing marked 18 O 2 at 600 °C under 25 MPa. The oxide scale was analysed by using Secondary Ion Mass Spectrometry (SIMS). The oxygen isotope profile shows that dissolved oxygen and supercritical water react with metals simultaneously. Dissolved oxygen changes the oxidation/reduction potential of supercritical water leading to an increase in the oxidation rate. The oxidation rate increases with increase in dissolved oxygen content in supercritical water. The mechanism of the effect of dissolved oxygen on oxidation is discussed.