The stress and strain field and the low cycle fatigue life of a structure member with holes are calculated theoretically and investigated experimentally.The calculated results show that it is reliable to calculate the...The stress and strain field and the low cycle fatigue life of a structure member with holes are calculated theoretically and investigated experimentally.The calculated results show that it is reliable to calculate the stress and strain field of a member with holes by using the shell structural elasto plastic finite element program,which has been designed and developed by the author.The satisfactory results are obtained from LCF life prediction of a member with holes by the advanced local stress and strain method.The calculation and tests show that the stress concentration of the tensile plane member is intensified and the fatigue life reduces drastically when its holes are densified in the direction perpendicular to that of tensile;the stress concentration is mitigated slightly but the fatigue life is also shortened when they are densified in the tensile direction.展开更多
Criteria for calculating low cycle fatigue strength of DZ22 superalloy under complex stress condition are considered.The fatigue life of the material under complex stresses can be predicted according to the criteria,p...Criteria for calculating low cycle fatigue strength of DZ22 superalloy under complex stress condition are considered.The fatigue life of the material under complex stresses can be predicted according to the criteria,provided its straight axial strengths and any straight axial S—N curve are available.For DZ22 as a kind of directionally solidified high temperature alloy,the low cycle fatigue comparative tests have been made between the uniaxial tension compression and tension torsion at 850℃ and show that the results of tests and calculations are in good agreement.展开更多
文摘The stress and strain field and the low cycle fatigue life of a structure member with holes are calculated theoretically and investigated experimentally.The calculated results show that it is reliable to calculate the stress and strain field of a member with holes by using the shell structural elasto plastic finite element program,which has been designed and developed by the author.The satisfactory results are obtained from LCF life prediction of a member with holes by the advanced local stress and strain method.The calculation and tests show that the stress concentration of the tensile plane member is intensified and the fatigue life reduces drastically when its holes are densified in the direction perpendicular to that of tensile;the stress concentration is mitigated slightly but the fatigue life is also shortened when they are densified in the tensile direction.
文摘Criteria for calculating low cycle fatigue strength of DZ22 superalloy under complex stress condition are considered.The fatigue life of the material under complex stresses can be predicted according to the criteria,provided its straight axial strengths and any straight axial S—N curve are available.For DZ22 as a kind of directionally solidified high temperature alloy,the low cycle fatigue comparative tests have been made between the uniaxial tension compression and tension torsion at 850℃ and show that the results of tests and calculations are in good agreement.
