Influence of annealing temperature on sensitisation behaviour and corrosion properties of an Al-6.8wt% Mg alloy
Abstract
Influence of annealing temperature on beta-(Al3Mg2) phase precipitation and corrosion properties of sensitised Al-6.8wt% Mg alloy is investigated. Sensitisation of specimens annealed at 320 degrees C results in IGC and SCC susceptibility. Microstructural characterization shows fine precipitation of Mg-rich phase forming nearly continuous film at grain boundaries, despite small precipitated fraction (0.5%), and grain boundary faceting. Sensitised specimens annealed at 265 degrees C are IGC susceptible, but SCC resistant. Precipitation at grain boundaries is discrete, although the precipitated fraction is greater (3%) than in specimens annealed at 320 degrees C. Potentiodynamic measurements show that of all measured parameters, charge density is in the strongest correlation with the NAMLT and SSRT results.
Source:
Materials and Corrosion-Werkstoffe Und Korrosion, 2016, 67, 8, 867-875Publisher:
- Wiley-V C H Verlag Gmbh, Weinheim
Projects:
- Ministry of Education, Science and Technological Development, Republic of Serbia
- Design of processing and welding of the high strength Al-Mg alloys for road and railway trasportation applications (RS-34018)
- Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy - DE-AC02-05CH11231
DOI: 10.1002/maco.201508709
ISSN: 0947-5117