LAUSR

Environment-assisted crack initiation in aluminum alloys is strongly related to the physical and chemical reactivity of intermetallic particles whatever their location, i.e. at grain boundaries or in the matrix. Therefore, this paper first focuses on the most recent contribution of micro-scale local probe techniques to the study of processes occurring at the coarse intermetallic particles that need to be taken into account in the initiation stage of environment-assisted cracking. A critical review of micro-scale electrochemistry, chemistry and analysis of the influence of stress on intermetallic particles leading to the micro-scale analysis of crack incubation is presented. Moreover, the contribution of hydrogen to the initiation of environment-assisted cracking remains a widely debated issue. Therefore, the second part of this paper more specifically reviews and summarizes the contribution of some specific local probe techniques to a better understanding of the contribution of hydrogen enrichment to environment-assisted crack initiation. Remaining challenges in future studies needed to fully elucidate hydrogen-assisted cracking mechanisms at the micro-scale are discussed.