Prediction method for propagating crack length of carbon-fiber-based composite double cantilever beam using its electromechanical behavior and particle filter

In order to develop the life prediction method under creep-fatigue loading for gas turbine combustion transition piece, creep-fatigue tests were carried out on both as-received and aged Ni-based superalloy Nimonic 263. Crack initiation and propagation behaviors for the smooth specimen were observed. An unique relationship was obtained between life fraction and the maximum surface crack length under triangular wave shape loading tests, except the results for the trapezoidal wave loading tests. The latter results were due to the over estimation of the surface crack length at the crack initiation. These were caused from an oxide film break during straining. In the case of removing the oxide film before the measurement of surface crack, the relationship between life fraction and the maximum surface crack length obtained as unique relationship regardless of triangular and trapezoidal strain wave shapes. Using the life prediction method proposed, which is based on maximum surface crack length, the damage of combustion transition piece materials in service was evaluated.

Download Full-text

Complete analytical solutions for double cantilever beam specimens with bi-linear quasi-brittle and brittle interfaces

International Journal of Fracture ◽

10.1007/s10704-018-0324-5 ◽

2018 ◽

Vol 215 (1-2) ◽

pp. 1-37 ◽

Cited By ~ 1

Author(s):

Leo Škec ◽

Giulio Alfano ◽

Gordan Jelenić

Keyword(s):

Cantilever Beam ◽

Analytical Solutions ◽

Double Cantilever Beam

Download Full-text

Double Cantilever Beam Measurement and Finite Element Analysis of Cryogenic Mode I Interlaminar Fracture Toughness of Glass-Cloth/Epoxy Laminates

Journal of Engineering Materials and Technology ◽

10.1115/1.1345527 ◽

2000 ◽

Vol 123 (2) ◽

pp. 191-197 ◽

Cited By ~ 38

Author(s):

Y. Shindo ◽

K. Horiguchi ◽

R. Wang ◽

H. Kudo

Keyword(s):

Fracture Toughness ◽

Finite Element Analysis ◽

Finite Element ◽

Cantilever Beam ◽

Double Cantilever Beam ◽

Mode I ◽

Interlaminar Fracture Toughness ◽

Element Analysis ◽

Interlaminar Fracture ◽

Delamination Crack

An experimental and analytical investigation in cryogenic Mode I interlaminar fracture behavior and toughness of SL-E woven glass-epoxy laminates was conducted. Double cantilever beam (DCB) tests were performed at room temperature (R.T.), liquid nitrogen temperature (77 K), and liquid helium temperature (4 K) to evaluate the effect of temperature and geometrical variations on the interlaminar fracture toughness. The fracture surfaces were examined by scanning electron microscopy to verify the fracture mechanisms. A finite element model was used to perform the delamination crack analysis. Critical load levels and the geometric and material properties of the test specimens were input data for the analysis which evaluated the Mode I energy release rate at the onset of delamination crack propagation. The results of the finite element analysis are utilized to supplement the experimental data.

Download Full-text