Studying　the　ignition　and　combustion　performances　of　modified　aluminum-based　metallic　fuels　in　variable　oxidizing　atmospheres　is　highly　important　for　large-scale　space　exploration.　In　this　study,　Al–B–Mg　multi-metal　composite　powders　(MMP)　were　prepared　using　the　mechanical　ball-milling　method.It　was　coated　respectively　by　ammonium　perchlorate　(AP),　lithium　perchlorate　(LP),　and　potassium　nitrate　(KN)　to　obtain　modified　multi-metal　composite　powder　fuels　(AP@MMP,　LP@MMP,　and　KN@MMP,　respectively)　by　a　recrystallization　method.　The　samples　were　characterized　and　their　thermal　oxidation,　ignition　and　combustion　processes　were　investigated　through　a　TG　and　laser-ignition　experiment　under　Air/H2O　environments.　The　results　show　that　the　MMP　samples　can　potentially　be　called　pure　aluminum　substitutes.　All　three　samples　exhibit　fast　ignition　characteristics　with　ignition　delay　times　of　2.95–6.75　ms　in　air.　AP@MMP　exhibits　the　highest　ignition　speed.　The　thermal　oxidation,　ignition,　and　combustion　properties　of　all　samples　decayed　with　increasing　water　content　in　the　atmosphere　(Air→Air+H2O→H2O).　AP@MMP　exhibits　a　significantly　more　intense　and　stable　combustion　overall　than　LP@MMP　and　KN@MMP.　This　study　expands　the　direction　and　application　range　of　aluminum-based　composite　metal　fuels,　guiding　their　applications　in　Air/H2O　environments.　©　2024