It　is　difficult　to　deposit　dense　intermetallic　compound　coatings　by　cold　spraying　directly　using　compound　feedstock　powders　due　to　their　intrinsic　low　temperature　brittleness.　A　method　to　prepare　intermetallic　compound　coatings　in-situ　employing　cold　spraying　was　developed　using　a　metastable　alloy　powder　assisted　with　post　heat　treatment.　In　this　study,　a　nanostructured　Fe(Al)/Al2O3　composite　alloy　coating　was　prepared　by　cold　spraying　of　ball-milled　powder.　The　cold-sprayed　Fe(Al)/Al2O3　Composite　alloy　coating　was　evolved　in-situ　to　FeAl/Al2O3　intermetallic　composite　coating　through　a　post　heat　treatment.　The　effect　of　heat　treatment　on　the　phase　formation,　microstructure　and　microhardness　of　cold-sprayed　Fe(Al)/Al2O3　composite　coating　was　investigated.　The　results　showed　that　annealing　at　a　temperature　of　600　degrees　C　results　in　the　complete　transformation　of　the　Fe(Al)　solid　solution　to　a　FeAl　intermetallic　compound.　Annealing　temperature　significantly　influenced　the　microstructure　and　microhardness　of　the　cold-sprayed　FeAl/Al2O3　coating.　On　raising　the　temperature　to　over　950　degrees　C,　diffusion　occurred　not　only　in　the　coating　but　also　at　the　interface　between　the　coating　and　substrate.　The　microhardness　of　the　FeAl/Al2O3　coating　was　maintained　at　about　600HV(0.1)　at　an　annealing　temperature　below　500　degrees　C,　and　gradually　decreased　to　400HV(0.1)　at　1100　degrees　C.　(C)　2008　Elsevier　Ltd.　All　rights　reserved.