溫度、應(yīng)力加速試驗對螺旋壓縮彈簧應(yīng)力松弛行為的影響.pdf

1、天津大學(xué)碩士學(xué)位論文溫度、應(yīng)力加速試驗對螺旋壓縮彈簧應(yīng)力松弛行為的影響姓名：尹西岳申請學(xué)位級別：碩士專業(yè)：材料學(xué)指導(dǎo)教師：師春生201112ABSTRACTThestressrelaxationisoneofthemostimportantformoffailuresforthesprmginsetwiceItaffectstheefficiencyofthemachineandthepreclsmn，sensitivity，stabi

2、lit、randreliabilityoftheinstrumentsTherefore，itissignificanttoresearchthestressrelaxation，investigatethemechanismoftherelaxationandforecastthescINlcelifeofspringatroomtemperatureThispaperinvestigatedthestressrelaxationof

3、thequenchedtemperedspringandthenormalizedspringmadeof60Si2Mnatdifferenttemperatures，differentloadsanddifferenttestdurationsunderstaticloadsThestressrelaxationtestingwascarrledoutwithadynamicspringtestingmachineandthestre

4、ssesrelaxationdataatdifferenttempcraturesandunderdifferentloadswerecollectedautomaticallyTheservicelivesofthetwodifferentspringsatroomtemperaturewerepredictedaccordingtothetheoryoftemperatureacceleratedstressrelaxationTh

5、eeffectSofthetemperature，loadandtestdurationonthemicrohardness，macroscopicresidualstress，latticedistortionandmicrostructureofthequenchedtemperedspringandthenormalizedspringwereinvestigatedusinghardnesstester，residualstre

6、ssinstrument，XRD，OM，SEMandTEMMeanwhile，themechanismOtstressrelaxationwasdiscussedTheresultsshowthatthestressrelaxationcurvesofspringwerecomposedot僦ostageswithdifferentrelaxationratesTherelaxationrateofthefirststagewaslar

7、gerthanthesecondstage，howeverthetimeofdurationofthefirststagewasshortthanthesecondoneTheloadlossratesoftenyearsforthequenchedtemperedspringandthenornlalizedspringatroomtemperaturearepredictedasO8％and297％，respectively，ind

8、icatingthatthespringwithquenched_temperedmlcrostmctu。epresentsbetterantirelaxationperformanceThemicrohardnessofspringschangedalittleduffngthestressrelaxationatlowtemperatureThemacroscopicresidualstressrelaxationofsprings

9、playsanimportantroleinthestressrelaxationofspringXRDanalysisshowsthatthemicrostresswhichinducedlatticedistortiondoesnotplayadecisiveroleinthewholerelaxationprocess，butthemacroscopicinternalstressinthespringsplaysanimport