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金属学报(英文版) 1999
EFFECTS OF MICROSTRVCTURE ON FATIGUE CRACK GROWTH BEHMIOR IN Ni-BASE SUPERALLOY GH586Keywords: superalloy,GH586,fatigue,crack,growth,threshold,grain,size,γ'-distribution Abstract: 1.IntroductionInmetalsandalloys,thenearthresholdfatiguecrackgrowthisfrequentlytermed'microstructurallysensitive'.Thisisduebothtotheappearanceofthefracturesllrface,whichisoftenfaceted,andtotilelargevariationsincrackgrowthratewhichcanbeobtainedbyalteringparameterssllchasgrainsize,yieldstrength,ortherelativeproportionsanddistributionsofphasesinthemicrostructure1].Thisimpliesthatsignificantimprotremelltintotalfatiguelifecouldbeachievedbychangingthemicrostructureofalloys.Therefore,itwouldbeveryadv…
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