简介:DeepcryogenictreatmenttechnologyofelectrodesisputforwardtoimproveelectrodelifeofresistancespotweldingofaluminumalloyLF2.Deepcryogenictreatmentmakeselectrodelifeforspotweldingaluminumalloyimprove.Thespecificresistivityofthedeepcryogenictreatmentelectrodesistestedandexperimentalresultsshowthatspecificresistivityisdecreasedsharply.ThetemperaturefieldandtheinfluenceofdeepcryogenictreatmentontheelectrodetiptemperatureduringspotweldingaluminiumalloyisstudiedbynumericalsimulationmethodwiththesoftwareANSYS.Theaxisymmetricfiniteelementmodelofmechanical,thermalandelectricalcoupledanalysisofspotweldingprocessisdeveloped.Thenumericalsimulationresultsshowthattheinfluenceofdeepcryogenictreatmentonelectrodetiptemperatureisverylarge.
简介:ThefatiguepropertyofAZ31magnesiumalloyanditsTIGweldedjointswereinvestigated.Theultrasonicpeeningtreatment(UPT)wasusedtoimprovethefatiguepropertyoftheTIGweldedjoints,whichwastreatedattheweldtoebytheUPTprocess.ThetestresultsshowthatthefatiguestrengthofthebasemetalofAZ31magnesiumalloysis57.8MPa,andthoseofthefilletjointandthetransversecrossjointarerespectively20.0MPaand17.2MPaat2×106cycles.ThefatiguestrengthsoftwokindsofweldedjointstreatedbytheUPTarerespectively30.3MPaand24.7MPa,whichhavebeenimprovedby51.5%and43.6%,respectively.Thefatiguelifeofthefilletjointspecimensisprolongedbyabout2.74timesandthefatiguelifeofthetransversecrossjointspecimensisprolongedbyabout1.05timeswhenthestressrangeisat40.0MPa.