In　this　work,　the　vaporizing　foil　actuator　welding　(VFAW)　has　been　used　for　impact　welding　of　aluminum　AA1060　to　copper　T2　sheets.　The　microstructural　feature,　mechanical　properties,　and　electrical　conductivity　of　Al-Cu　welded　joints　were　investigated.　The　VFAW　process　was　simulated　by　LS-DYNA　to　analyze　the　effect　of　impact　velocity　and　angle.　The　evolution　of　the　microstructure　of　the　welding　interface　was　revealed　by　smoothed　particle　hydrodynamics　numerical　simulation.　The　qualities　of　Al-Cu　joints　were　evaluated　by　microstructure　observations,　lap　shear　tensile　testing　and　resistance　measurements.　The　results　show　that　the　Al-Cu　joints　have　a　flat　welding　interface　at　the　discharge　voltage　of　8 kV,　but　the　joints　failed　at　the　interface　due　to　the　residual　Al2O3.　Owing　to　the　change　in　interfacial　effective　plastic　strain　and　impact　pressure,　increasing　the　discharge　voltage　resulted　in　the　transition　of　the　interface　waveform　from　flat　to　wavy,　and　the　site　of　tensile　failure　changed　from　the　welding　interface　to　the　Al　base　metal.　The　results　of　element　analysis　showed　that　there　was　a　transition　zone　consisting　of　Al-Cu　intermetallic　compounds　at　the　interface.　This　transition　zone　would　change　from　intermittent　to　continuous　and　become　thicker　after　increasing　the　discharge　voltage.　Variations　in　discharge　voltage　can　change　the　resistivity,　thickness,　and　area　of　the　welding　region,　which　in　turn　affects　the　joint　resistance.　©　ASM　International　2024.