简介：ThemicrostructureandtensilepropertiesofSn-9Znsolderunderdifferentcoolingandagingconditionwerestudied.Duringsolidification,thedistributionofZn-richphasesandgrainsizeinthemicrostructureofSn-9Znsolderweredecidedbythecoolingrate.TheZn-richphaseinSn-9Znsolderunderfurnacecooling,aircoolingandwatercoolingmediawasseparatelyexistedascoarsendendriticandneedlelikeshape,fineneedlelikeshapeandveryfinerod-likeshape,respectively.Afteraging,thecoarsendendriticwasbrokenandthecoarsenneedlelikeZn-richphasewaspartlychangedintofinedistributionofZn-richphaseforSn-9Znsolderwithfurnacecooling,andtherod-likeZnphaseintheSn-9ZnsolderunderwatercoolingwaschangedtoconglomeratedZnwithneedleshape.DuringtensiletestingonSn-9Znsolder,tensilestrengthandductilityreachedthebestwithwatercooling,butdecreasedwithagingeffect.Meanwhile,theductilityofsolderwithaircoolingandthestrengthofsolderwithfurnacecoolingincreasedwithaging.Thefracturemodewasductileandwasindependentofcoolingmediaandagingeffect.Thesizeanddepthofdimplesdecreasedfromwater,furnacetoaircooling.Afteraging,numberandsizeofdimplesincreasedonthesolderwithfurnacecoolingandaircooling.ThechangeonthesizeofdimplesfortheSn-9Znsolderunderdifferentcoolingconditionandwithagingeffectwasaccordancetothetensileproperties.

简介：ThediffusionbondingofAZ3\BMgalloyandQ235steelwasinvestigatedwithaZn-5AIalloyasinterlayerandunderdifferentholdingtimerangingfrom3to1200s.Themicrostructureandphasecompositionsofbondedjointswerecharacterizedbyscanningelectronmicroscopy(SEM),energydispersivespectrometer(EDS)andX-raydiffraction(XRD)methods.TheshearstrengthofMgalloy/steeljointswasmeasuredbytensiletester.Itwasfoundthatthemicrostructureofbondedjointsevolveddramaticallyalongwiththeprolongationofholdingtime.Undertheholdingtimeof3s,themainpartofjointwascomposedofMgZn2phaseanddispersedAl-richsolidsolutionparticles.Whenincreasedtheholdingtimemorethan60s,theexcessivesolutionofAZ3\Bintotheinterfacialreactionarealedtotheformationofcoarsephaseandeutecticmicrostructure,andalsothecomplexFe-AlandMg-Al-ZnIMCsattransitionlayerclosedtoQ235steelside.Accordingtothetensiletestingcharacterizations,thejointsobtainedunderholdingtimeof3sexhibitedthebestshearstrengthof84MPa,andthefractureoccurredattheintermediarypartofjointwheretheflexibleAl-richsolidsolutionparticlescouldhelptoimpedethemicrocrackpropagations.Withprolongingtheholdingtimeto600s,theshearstrengthofjointswasdeterioratedenormouslyandthefracturepositionwasshiftedtothetransitionlayerpartclosedtoQ235steel.