Based on cycle strain damage prediction of the crack growth behavior of elliptic surface crack
According to the low cycle fatigue strain damage,a unit average damage parameter over the cyclic plastic zone along the crack extending direction is defined,and a new fatigue crack growth rate prediction model (LCF-FCGM) is established.Then combined with Newman-Raju formula,simulation of the fatigue crack growth problem of a half elliptic surface crack in tension plate under cyclic loading is fulfilled.The fatigue crack growth rate curve of Al 7075-T6 alloy predicted by LCF-FCGM agrees well with that obtained from the corresponding test.Assuming that the shape of the surface crack front keeps elliptic and is controlled by two critical points: the deepest point and the surface point,a numerical approach based on materials low cycle fatigue properties is developed to analyze the configuration evolution of surface cracks during fatigue crack growth.The new approach is well applied to Al 7075-T6 alloy surface cracked plate,and six different initiate crack shapes are discussed and all reflect the same phenomenon of round first to oval again,which are consistent with the test results.
fatigue crack propagation low-cycle fatigue damage Newman-Raju formula elliptic surface crack Al 7075-T6 alloy
LONG CHEN LIXUN CAI KAIKAI SHI
School of Mechanics and Engineering,Southwest Jiaotong University,Chengdu,Sichuan 610031,China
国际会议
北京
英文
1-10
2013-06-16（万方平台首次上网日期，不代表论文的发表时间）