The　3003　aluminum　alloy　tube　and　1Cr18Ni9Ti　stainless　steel　rod　were　welded　by　magnetic　pulse　welding.　The　influence　of　the　field　shaper　gap　on　the　connection　effect　of　the　magnetic　pulse　welding　joint　was　studied.　The　welding　results　were　further　analyzed　by　empty　tube　deformation　experiments.　The　results　show　that　the　magnetic　force　of　the　outer　tube　near　the　field　shaper　gap　is　decreased,　and　therefore　the　deformation　speed　of　the　outer　tube　near　the　field　shaper　gap　is　smaller　than　those　of　other　positions　during　the　welding　process.　However,　in　the　process,　a　circumferential　impact　angle　of　the　outer　tube　to　the　inner　rod　has　been　generated　by　the　deformation　speed　difference,　so　that　an　axial　connection　along　the　joint　is　created　near　the　field　shaper　gap,　which　is　beneficial　to　the　connection　of　the　aluminum　alloy　tube　to　stainless　steel　rod.　Different　impact　gaps　have　their　corresponding　optimal　discharge　voltage　ranges.　Under　the　influence　of　the　field　shaper　gap,　excessive　voltage　leads　to　joint　cracking.　©　2018,　Editorial　Board　of　Journal　of　Tianjin　University(Science　and　Technology).　All　right　reserved.