FLUCTUATING STRESS - ITESCAM：脉动应力- itescam

FLUCTUATING STRESSVariable loading is often characterized by an amplitude component σa as ordinate a

FLUCTUATINGSTRESS a Variableloadingisoftencharacterizedbyanamplitudecomponentσas m ordinateandasteadycomponentasabscissa.Definedintermsof σ __ximumstress__xandminimumstressσminthecoordinatesareasfollows: σ Thedesigner’sfatiguediagramisdepictedinFig.29.12. am Ifoneplotscombinationsandσthatpartitionpartsurvivalfrompartfailure, σ Sut afailurelocusisdefined.Propertiessuchasulti__tetensilestrength_,yield SySyc strengthintension_,yieldstrengthincompression_,enduran__strength SeSfm _,orfatiguestrength_appearasaxisinter__pts.Intherangeinwhichσ isnegativeandfatiguefractureisathreat,thefailurelocusistakenasa horizontallineunlessspecificexperimentaldataallowanotherlocus.Inthe m rangeinwhichσispositive,thepreferredlocusisGerberorA__E-Elliptic.The Good__nandSoderberglocih__e