A　novel　Er-doped　Mg-Zn-Al　solder　was　developed　by　using　ultrasonic　vibration　technology.　The　inclusions　in　the　solder　were　analyzed.　The　microstructure　of　the　solder　and　its　soldering　lap　joint　was　investigated,　and　the　shear　strength　of　the　joint　was　measured.　It　was　found　that　the　inclusions　in　the　solder　decreased　greatly,　the　alpha-Mg　phase　and　Al3Er　compound　were　broken　up　into　granular　structure　after　ultrasonic　vibration　treatment.　The　alpha-Mg　phase　and　Al3Er　compound　in　the　soldered　joint　showed　similar　structure　as　that　of　the　original　solder.　The　average　shear　strength　of　the　soldered　joints　by　using　the　ultrasonic　treated　filler　metal　was　almost　1.25　times　as　large　as　that　soldered　by　the　traditional　one.　(C)　2014　Elsevier　B.V.　All　rights　reserved.