Microstructure　evolution　has　been　investigated　for　magnetic　pulse　welding　of　dissimilar　aluminium　and　magnesium　alloys　using　optical　microscopy,　laser　confocal　microscopy　and　electron　backscatter　diffraction.　The　welded　joints　were　made　with　discharge　voltages　of　4　kV,　4.5　kV　and　5　kV　and　they　are　characterised　by　the　aluminium　region,　the　weld　interface　and　the　magnesium　region.　The　interfacial　waves　become　more　regular　and　much　smoother　with　increasing　discharge　voltage　from　4　kV　to　5　kV.　The　grains　were　extremely　refined　and　the　grain　size　became　larger　with　increasing　distance　to　the　weld　interface　at　a　discharge　voltage　of　5　kV.　The　gradual　grain　refinement　closer　to　the　weld　interface　can　be　attributed　to　dynamic　recrystallization.　Different　recrystallization　behaviour　was　observed　for　the　aluminium　region　and　the　magnesium　region　near　the　weld　interface.　The　occurrence　of　the　extension　twinning　{1　0　(1)　over　bar　2}　in　the　dynamic　recrystallized　grains　indicating　twin　related　dynamic　recrystallization　behaviour　in　the　magnesium　region　near　the　weld　interface.　(C)　2015　The　Society　of　Manufacturing　Engineers.　Published　by　Elsevier　Ltd.　All　rights　reserved.