Rhenium　is　the　key　element　for　improving　the　mechanical　properties　in　gamma/gamma＇　structure　single-crystal　Nibased　superalloys,　but　its　oxidation-induced　evaporation　results　in　a　detrimental　decrease　in　corrosion　resistance.　The　in　situ　Re　evaporation　process　of　a　single　lamella　of　a　high　Re-containing　Ni-based　superalloy　is　recorded　in　an　environmental　transmission　electron　microscope.　The　local　aggregation　of　Re　in　the　inner　border　of　the　gamma　phase　and　subsequent　evaporation　forms　channels　for　the　accelerated　oxidation　of　the　base　and　other　elements.　The　real　oxidation　process　of　Re　evaporation　provides　detailed　and　essential　information　on　corrosive　gas　resistance　properties　at　the　nanoscale.　(C)　2021　Acta　Materialia　Inc.　Published　by　Elsevier　Ltd.　All　rights　reserved.