1、西安石油大學碩士學位論文含氫環(huán)境中管線鋼性能退化規(guī)律研究姓名：趙穎申請學位級別：碩士專業(yè)：材料加工工程指導教師：王榮20040514Subject：Investigationsonthepropertiesdegradationregularitiesofpipelinesduringexposureto建hydrogenabsorbedenvironmentMajor：ProcessingEngineeringofMaterialN鈺

2、me：確a。Yi毯(Signa協(xié)re)j滔L墜唑!Instructor：WangRong(Signature)。。。‘’1。。。‘‘。。。”’’?！籄BSTRACTInthecorrosiveenvironment，hydrogenwillbepermeatedintothepipelinebycmhodicreactionhydrogenandelectrochemicalprotectionItwillcausehydrogene

3、mbrittlement，whichresultsinthedegradationofthepropertiesandisthesourceoffractureOnthebasisofsuchbackground，tensiletestsandslowstrainratetests(8SRT)wereusedtoinvestigatethemechanicalbehaviorsofX70pipelinesteelafterelectro

4、chemicalhydrogenchargingElectro—chemicalmethodswereusedtoinvestigatetheanodicdissolutionofX70pipelinesteelinthesimulatednearneutralsoilsolutionmS4100％C02solution)andNS4solutionafterelectro—chemicalhydrogenchargingTensile

5、testresultsofprechargedsmoothspecimensshowthathydrogenhasliRleinfluenceonthetensilestrengthofX70pipelinesteelanddecreasestheplasticityofX70pipelinesteel，therebythefractureductilityandthefracturestrengthreduceconsiderabl甄

6、theplasticpropertiesdecreasesuccessivelyasthehydrogenconcentrationC—increaseAttheslowstrainratetension(SSRT)condition，dynamicelectrochemicalcharging謝mhydrogendecreasestheplasticityofthesmoothspecimensofX70pipelinesteelco

7、nsiderablyTheUnotchedspecimensofX70pipelinesteelwereusedtochargewithhydrogenin05mol／LI12S04solution，andthenextendedinairtofractureforobtainingthenotchfracturetoughnessThecriticalcurrentdensitytocausehydrogendamageis50mA／

8、cmzThecorrespondingcriticalhydrogenconcentrationis097810～Whenthehydrogenconcentrationislessthan0978x10每thenotchfracturetoughnessincreasesllg％。Whenthehydrogenconcentrationismorethan0978xt0～，thenotchfracturetoughnessdecrea

9、seswiththelinearrelationshipofthehydrogenconcentrationCo，ie，Kc(H)2906w1773CoOntheslowstrainratetensiontestswithdynamicallychargingwithhydrogeninO。5mol／L1t2S04solution，thenotchfracturetoughnessdecreaseswithexponent／a／fimc