调质q690d钢焊接性能分析及热影响区组织预测-analysis of welding performance of quenched and tempered q690d steel and prediction of microstructure in heat affected zone.docx

下载文档 降价啦

22
0
约5.87万字
约 90页
2018-08-07 发布于上海
举报
版权申诉
保障服务

调质q690d钢焊接性能分析及热影响区组织预测-analysis of welding performance of quenched and tempered q690d steel and prediction of microstructure in heat affected zone.docx

1、本文档共90页，可阅读全部内容。
2、有哪些信誉好的足球投注网站（book118）网站文档一经付费（服务费），不意味着购买了该文档的版权，仅供个人/单位学习、研究之用，不得用于商业用途，未经授权，严禁复制、发行、汇编、翻译或者网络传播等，侵权必究。
3、本站所有内容均由合作方或网友上传，本站不对文档的完整性、权威性及其观点立场正确性做任何保证或承诺！文档内容仅供研究参考，付费前请自行鉴别。如您付费，意味着您自己接受本站规则且自行承担风险，本站不退款、不进行额外附加服务；查看《如何避免下载的几个坑》。如果您已付费下载过本站文档，您可以点击这里二次下载。
4、如文档侵犯商业秘密、侵犯著作权、侵犯人身权等，请点击“版权申诉”（推荐），也可以打举报电话：400-050-0827(电话支持时间：9:00-18:30)。

调质q690d钢焊接性能分析及热影响区组织预测-analysis of welding performance of quenched and tempered q690d steel and prediction of microstructure in heat affected zone

AbstractWeldingplaysanimportantroleduringthehighstrengthlowalloysteel,suchasQ690Disprocessedintotheengineeringstructurewhoseservicelifeiscloselyrelatedwiththemicrostructureandpropertyoftheweldingjoints.Tocontroltheweldmentquality，therefore,themicrostructureandpropertypredictionoftheweldingjointsbecomesahotstudytopic.Thisthesiswasconcentratedontheweldabilityinvestigationandmicrostructureandpropertypredictionbynumericalsimulationof10mmthicknessQ690Dplates.TheGleeble-1500Dthermal-mechanicaltesterandL78-RITAquenchingdilatometerwereemployedtofinishthethermalsimulationtestsofQ690Dsteel,meanwhile,theSH-CCTdiagramwasobtained.Aftermulti-passesweldingbyGMAWmethod,themicrostructureoftheweldmentwasobservedbyOMandSEM.Thehardness,tensileandimpacttestswereimplementedtoinvestigatethemechanicalproperties;ThetemperaturedistributionofweldingprocessforQ690DsteelwassimulatedbyANSYS.Forthesimulatedcontinuouscoolingtransformationofcoarsegrain,thecriticalformationt8/5ofbainite,proeutectoidferriteandpearlitewere4s,500s,1200srespectively;Whenthet8/5wasattherangeof4.4~30s,themicrostructurewerelathmartensiteandbainite,and100%bainitewasobtainedwhent8/5wasrangedat60~200s;Thegrainsofparentmetalwererefinedatapeaktemperaturerangeof880~1150℃,whilethegrainswerecoarseningwhenpeaktemperatureisupto1150℃;Thefractionofferriteat880℃washighenoughtodecreasethehardness;Whenthepeaktemperatureofsecondthermalcyclewas800℃,thegrainswerepartlyrefinedattheboundaryandbainitewasobtained.Themicrostructureinweldingzonewasmainlyacicularferrite,andlathmartensitemixedbybainitewereobtainedintheheataffectedzone(HAZ)ofQ690Dweldment;TherealsoexistedasoftenzoneintheHAZ;The-20℃impactvalueofweldingzonewasoverto100J,whenvalueofHAZwasapproximately50J;Theincreasingcurrentdecreasedtheimpactvalueoffusionzone;Thetensilestrengthofallweldmentswasover780MPawhichmeetperformancerequirements.OnthebasisofweldingthermalcyclesimulationresultsandSH-CCTdiagram,thewidthandmicrostructuredistributiononHAZofallweldingpasseswereaccuratelypredictedthro