Prediction of fatigue life of spot welding connections subjected to unidirectional dynamic shear load

Transcription

1 mme.modares.ac.ir * - - golabi-s@kashanu.ac.ir87757 *. ST DIN55. C-G -.. ASME ST 9 4 : 9 : 9 4 : Predictionoffatiguelifeofspotweldingconnectionssubjectedto unidirectionaldynamicshearload AliHabibizadeh Sa'idGolabi * -DepartmentofMechanicalEngineering,NajafAbadBranch,IslamicAzadUniversity,NajafAbad,Iran -DepartmentofMechanicalEngineering,UniversityofKashan,Kashan,Iran P.O.B.87757Kashan,Iran,golabi-s@kashanu.ac.ir ARTICLEINFORMATION ABSTRACT OriginalResearchPaper Received5July4 AcceptedSeptember4 AvailableOnlineOctober4 Keywords: Fatiguelife Resistancespotwelding Finiteelement Fatiguetestmachine Disjoiningofspotweldsinsteelsheetsbecauseoffatiguefailureisoneofthemainreasonsfor noiseinusedcars.fatiguelifeofspotweldingconnectionsofststeelsheets,usedincar industry,withmmnuggetdiameterandsubjectedtouniaxialdynamicshearloadisstudiedand determinedinthisresearch. Sheetthicknessandotherspotwelding parameters includingweld pitchareconsideredandcomparedaccordingtoc-g standard utilizing the test sample selectedaccordingtodin55standard.abaqusandfe-safesoftwareisusedforstaticand fatiguelifeanalysisrespectively.togeneratestress-numberoflifecycle(s-n)diagram,the equivalent fully reversed load is determined using Goodman and Gerber theories since the appliedloadisunidirectional.theresultantfiniteelementresultswereverifiedexperimentallyby fatigue test machine designed and manufactured during this study by the authors. The finite elementresults showed goodagreementwith Gerbercriterionanditwasconcludedthatwith increaseinsheetthickness,bothstaticstrengthandfatiguelifewouldbeincreased.theresults also indicate that the weld pitch has no effect on fatigue life. Stress life graph for mm nugget diameterspotweldonstsheetisthemostimportantoutputofthisresearchthatcanbeused inautomobileindustry..[] Pleasecitethisarticleusing: : A.Habibizadeh,S.Golabi,Predictionoffatiguelifeofspotweldingconnectionssubjectedtounidirectionaldynamicshearload,ModaresMechanicalEngineeringVol.4,No. 5,pp.-8,5(InPersian)

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