In this paper,a methodology integrating crystal plasticity(CP),the eXtended finite element method(XFEM)and the cohesive zone model(CZM)is developed for an Al-Cu-Mg alloy to predict fatigue crack propagation(FCP)across...In this paper,a methodology integrating crystal plasticity(CP),the eXtended finite element method(XFEM)and the cohesive zone model(CZM)is developed for an Al-Cu-Mg alloy to predict fatigue crack propagation(FCP)across grain boundary(GB)of Al-Cu-Mg alloy during stageІІ.One GB model is incor-porated into FCP constitutive law to describe grain interaction at GB.A bicrystal containing GB is built up to simulate FCP behavior through L participated GBs.Modelling features including GB characteristic,cumulative plastic strain(CPS)distribution and crystal slipping evidence can be identified.The numer-ical results are compared with published experimental data to check the accuracy of model.This work demonstrates that the combination of CP containing GB constitutive laws,XFEM and CZM is a promising methodology in predicting twist angle-controlled crack deflection through GBs.展开更多
Previous studies,including ASME and RCC-MR standards,did not consider the influence of environmental factors on the ratcheting boundary of the material,and only a unified ratcheting boundary was proposed.In this paper...Previous studies,including ASME and RCC-MR standards,did not consider the influence of environmental factors on the ratcheting boundary of the material,and only a unified ratcheting boundary was proposed.In this paper,thermal aging was taken into consideration,and the effect of thermal aging time on the ratcheting boundary of 316 LN austenitic stainless steel was characterized by the efficiency diagram rule.The results show that,when the secondary ratio U is small,there is no significant difference in ratcheting boundary between the original material and the thermal aged material.When the secondary ratio U is large,the ratcheting boundary of the material presents a slight upward trend with the increase of thermal aging time.Compared with ASME and RCC-MR standards,it is found that RCC-MR is conservative.Based on the evolution of the efficiency index V with the number of cycles,it is more conservative and reasonable to choose the stage when the efficiency index V develops into a constant.展开更多
基金supported by the National Natural Science Foun-dation of China(51901073).Qi Zhao was Visiting Scholar to the Soete Laboratory at Ghent University and supported by China Scholarship Council when this work is done.The authors wish to express their gratitude to Van Lang University,Vietnam for finan-cial support for this research.
文摘In this paper,a methodology integrating crystal plasticity(CP),the eXtended finite element method(XFEM)and the cohesive zone model(CZM)is developed for an Al-Cu-Mg alloy to predict fatigue crack propagation(FCP)across grain boundary(GB)of Al-Cu-Mg alloy during stageІІ.One GB model is incor-porated into FCP constitutive law to describe grain interaction at GB.A bicrystal containing GB is built up to simulate FCP behavior through L participated GBs.Modelling features including GB characteristic,cumulative plastic strain(CPS)distribution and crystal slipping evidence can be identified.The numer-ical results are compared with published experimental data to check the accuracy of model.This work demonstrates that the combination of CP containing GB constitutive laws,XFEM and CZM is a promising methodology in predicting twist angle-controlled crack deflection through GBs.
基金the National Natural Science Foundation of China(Grant No.51435012)。
文摘Previous studies,including ASME and RCC-MR standards,did not consider the influence of environmental factors on the ratcheting boundary of the material,and only a unified ratcheting boundary was proposed.In this paper,thermal aging was taken into consideration,and the effect of thermal aging time on the ratcheting boundary of 316 LN austenitic stainless steel was characterized by the efficiency diagram rule.The results show that,when the secondary ratio U is small,there is no significant difference in ratcheting boundary between the original material and the thermal aged material.When the secondary ratio U is large,the ratcheting boundary of the material presents a slight upward trend with the increase of thermal aging time.Compared with ASME and RCC-MR standards,it is found that RCC-MR is conservative.Based on the evolution of the efficiency index V with the number of cycles,it is more conservative and reasonable to choose the stage when the efficiency index V develops into a constant.
