TheWeibullstressparameterscalibrationuponthetoughnessscalingmodelbetweencrackshavingdifferentconstraintOriginalResearchArticle

Anextensiveinvestigationhasbeencarriedoutonthesensitivityparametersdeterminationdescribingthefracturebehaviourofthebodywithacrackwithrespecttothecharacterchangeofthetruestress–straincurvewiththedominantregionofLuedersdeformation.ThispaperpresentstheconsiderationonthechangejudgementoftheJ-integralandtheconstraintasthebaseparametersoftwo-parameterfracturemechanics.TheWeibullstressmodelforcleavagefractureoriginallyproposedbyBeremingrouprequirescalibrationoftwomicromechanicsparameters(m,σu).TheWeibullstressσwseemstobeaparameterforthepredictionofcleavagefailureofcrackedbodiesandthestudyisfocusedontheassessmentoftheeffectsofconstraintlossonthecleavagefracturetoughness(Jc).ToquantifytheeffectsoftheconstraintvariationonthecleavagefracturetoughnesstheformofthetoughnessscalingmodelbasedontheWeibullstressσwisinvestigated.LocalmaterialparametershavebeencalculatedfromBereminapproachandthecalibrationisperformedonvariousapproaches.Methodsarebasedontheweakestlinkassumptionandtheincrementalfractureprobability,whichdependsnotonlyonthemaximumprincipalstress,butalsoontheequivalentplasticstrain.Thefractureresistancehasbeenassessedusingdatafromstatictestsofthreepointbendspecimens.