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11 个结果
  • 简介:WiththemodifiedAlmenmethod,theforminganddevelopmentprocessofresidualstressinathermalsprayedcoatinghasbeenobtained.Thetestresultsidentifythattheresidualstressinacoatingisdependoncoatingmaterialproperties,techniqueandcoatingthickness.Thepaperpaysmuchattentiontothehysteresisbetweenthecoatingtemperatureandresidualstressinthecoatingorbetweentheappliedstressandthestrainofthecoating,andconfirmsthatthefactisresultedfromthe"GasFix"characterofathermalsprayedcoating.

  • 标签: 热喷涂 涂层 残余应力 动力学 滞后现象
  • 简介:NondestructivetestofweldresidualstressesbyacoustoelastictechniqueJiaoFujie;ZhangWenjunandYuanZhikang(ShanghaiUniversityofEngi...

  • 标签: acoustoelasticity WELD RESIDUAL STRESS ULTRASONIC measurement
  • 简介:Thisstudydevelopedasequentialcouplingfiniteelementproceduretopredictresidualstressesofsteelpipeswithlongitudinalwela\circumferentialweldandspiralweld.Theresultsshowthattheresidualstressinheataffectedzone(HAZ)ishigherthanthatinweldforspiralweldpipe.Forthecircumferentialweldpipeandspiralweldpipe,theresidualstressininnersurfaceishigherthanthatinoutersurface.However,forthespiralweldpipe,theresidualstressininnersurfaceissmallerthanthatinoutersurface.Thehoopresidualstressofcircumferentialweldpipeishigherthanthatoflongitudinalweldpipe,whiletheaxialresidualstressofcircumferentialweldpipeissmallerthanthatoflongitudinalweldpipe.Thehoopstressesforcircumferentialweldpipeandaxialstressforlongitudinalweldpipehaveexceededtheyieldstrengthofbasemetal.Withtheincreaseofhelixangle,thehoopstressdecreaseswhiletheaxialstressincreases.Forthespiralpipe(α=30°to50°),boththehoopstressandaxialstressarerelativelysmall.Thespiralpipe(helixanglerangingfrom30°to50°)ishelpfultoreducestresscorrosioncracking(SCC)anditisrecommendedtomanufacturethesteelpipe.

  • 标签: 焊接残余应力 钢管 环向应力 轴向应力 类型 螺旋焊缝
  • 简介:MagneticBarkhausennoise(MBN)isaphenomenonofelectromagneticenergyduetothemovementofmagneticdomainwallsinsideferromagneticmaterialswhentheyarelocallymagnetizedbyanalternatingmagneticfields.AccordingtoFaraday’slawofelectromagneticinduction,thenoisecanbereceivedbythecoilattachedtothesurfaceofthematerialbeingmagnetizedandthenoisecarriesthemessageofthecharacteristicsofthematerialsuchasstresses,hardness,phasecontent,etc.Basedonthecharacteristicofthenoise,researchingabouttherelationshipbetweentheresidualstressintheweldingassemblyandthenoisearecarriedout.Furthermore,dataprocessisperformedbyRMS(RootMeanSquare)equationandPowerSpectrumanalysis.

  • 标签: Barkhausen噪音 磁域 残差应力 能量光谱
  • 简介:Whenmeasuringresidualstressofcoarse-grainaluminumalloyusingX-raydiffractionmethod,thediffractionprofileshowstwopeaksandpositionofmeasured2dwillbechanged,whichleadtoaninaccuratemeasurementresult.Hence,inthispaper,somemethodswereemployedtoimprovethemeasurementaccuracy.Duringthemeasuringprocess,differentparameters(diameterofirradiatedarea,Ψ-oscillationrangeandexposuretime)wereselectedandprofilepeakshiftmethodwasutilized.Moreover,whenthe20ofprofileswasdetermined,differentcalculationmethodswereusedtocalculatetheresidualstress.TheresultsshowthatdiameterofirradiatedareaandΨ-oscillationrangehavesignificantinfluenceonthemeasuringresult.Forstressvaluecalculateddirectlyfromthetestequipment,crosscorrelationmethodismoreaccuratethantheabsolutepeak.Furthermore,anothertwocalculationmethodsofslopewith2θ-sin~2Ψande-sin~2Ψwereusedtocalculatethestressbasedonparameters(2θ,ε)obtainedfromcrosscorrelationmethod.Itisconcludedthat20-sin~2Ψmethodcanfurtherimprovethemeasurementaccuracy.

  • 标签: X射线衍射法 残余应力 铝合金 粗晶 测定 测量精度