Crack linkup: An experimental analysis
Tóm tắt
TheT
ɛ
*
integral was used to assess stable crack growth and crack linkup in 0.8 mm thick 2024-T3 aluminum tension specimens with multiple site damage (MSD) under monotonic and cyclic loads. TheT
ɛ
*
values were obtained directly from the recorded moiré fringes on the fracture specimens with and without MSD. TheT
ɛ
*
resistance curves of these fracture specimens of different geometries were in excellent agreement with each other. The results suggest thatT
ɛ
*
is a material parameter which can be used to characterize crack growth and linkup in the absence of large overloading.T
ɛ
*
based crack growth and net-section-yield based crack linkup criteria for MSD specimens are proposed. The crack tip opening angle (CTOA) criterion can also be used to correlate crack growth larger than 2 mm.
Tài liệu tham khảo
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