The　work　aims　to　study　in-flight　particles,　splat　particles　and　coating　structure　produced　during　arc　spraying　of　AlMg/Al2O3　cored　wires,　as　well　as　impact　resistance　of　the　coatings.　Two　kinds　of　Al-base　cored　wires　containing　micron-grade　Al2O3　particles　were　developed.　The　collected　in-flight　particles　and　splats　particles　produced　during　arc　spraying,　as　well　as　coating　microstructure　were　characterized　with　SEM.　Impact　resistance　of　the　coatings　was　tested　with　a　self-made　apparatus.　Three　different　types　of　in-flight　particle,　namely,　AlMg,　AlMg　clad　Al2O3,　Al2O3,　were　generated　during　arc　spraying　of　AlMg/Al2O3　cored　wires.　With　the　decrease　of　Al2O3　particle　size,　the　AlMg　clad　Al2O3　particles　consisted　of　thicker　AlMg　film　and　more　Al2O3　particles.　The　splat　shapes　were　irregular　and　complex,　and　the　surfaces　were　uneven　and　subject　to　sputtering.　The　coating　structure　was　compact　and　less　defective.　When　the　particle　size　range　of　Al2O3　particles　was　400∼500　μm,　the　average　area　content　of　Al2O3　particles　on　the　surface　of　AlMg/Al2O3　coating　was　5.52%,　but　it　was　13.54%　When　the　particle　size　range　is　30∼50　μm.　Indicating　that　more　Al2O3　particles　accumulated　in　the　coating　containing　Al2O3　particles　of　small　particle　size.　Under　the　effects　of　500　cycle　cyclic　impact　tests,　the　AlMg　coating　and　AlMg/Al2O3　coating　exhibited　no　obvious　radial,　circular　cracks　and　large　area　flaking,　but　obvious　plastic　deformation　existed.　The　content　of　Al2O3　particles　increases　as　the　particle　size　of　Al2O3　particles　decreases.　The　as-prepared　AlMg/Al2O3　coating　absorbs　most　of　the　impact　work　through　plastic　deformation,　reduces　possibility　of　impact　fatigue　crack　generation,　and　maintains　a　good　bonding　between　coating　and　substrate.　©　2018　Chongqing　Wujiu　Periodicals　Press.　All　rights　reserved.