1420鋁鋰合金的激光焊接.pdf

1、國內圖書分類號：TG665單位代碼：學號：密級：審‘79262010005$200213015公開北京工業(yè)大學碩士學位論文英文并列題目L』塹量B塑星L墜l盥gQ墅!壘2Q△墜型衛(wèi)噍塑型魚生墜l!!塾型叢△U三叢研究生姓名壘擅直專業(yè)：光堂互捏研究方向：邀盤撾魁加王導師姓名：肖苤遺職稱：塑援論文報告提交日期：!Q蛭生旦塹目學位授予日期授予單位名稱和地址：I￡塞王些友芏韭夏立翹田匡堊巫園!業(yè)呈北京工業(yè)大學工學碩士學位論文Abstract142

2、0Aluminumlithiumalloyswelding、Ⅳi也hi曲powerlaserarestudiedsystematicallyinthispaperFirstlythethresholdoflaserdeeppenetrationweldingfor1420Al—LialloyandtheparametersthathaveeffectOnthresholdarestudiedinexperimentsTheresults

3、showthatthethresholdusingYAGlaserisobviouslylowerthanthatusingC02laserbecauseofthedifferentabsorptionisfromlaserwavelengthFurthermore，tIleoxidationfilmonthesurfaceof1420A1Lialloyisbenefittoincreasingtheabsorptionandreduc

4、ingthethresholdTherearelargenumberofalloyelements晰mlowermeltingandboilingpointssuchasMgandLiin1420A1LialloySOthethresholdof1420A1一LialloyislowerthancommonaluminumalloysSecondlytheweldabilitiesof1420AlLialloyarestudiedint

5、hispaperItisfoundthatthemainproblemduringtheprocessoflaserweldingof1420AI—LialloyisthattheweldporositywhichmainlyproducedbytheoxidationfilmPreweldtreatmentisakeyfactortoeliminateweldpores，poreratioCallbedecreasedbyremovi

6、ngeachsurfacefilmofO。05mmthickness，iftheremovingthicknessislargerthanO15ram，noporesarediscoveredintheweldFinallythebuttweldingexperimentsarecarriedoutwithdifferentprocessingparametersTheresultofjoint’Squalityandmicrostru

7、ctureareobservedbyopticalandscanningelectronmicroscopeTheinfluenceofmechanicalpropertiesonweldjointsisinvestigatedTheresultsoftensiletestshowthattheyieldstrengthofweldingjointswithoptimizedprocessingparametersandpreweldt