A Semi-elliptical Crack Modeling and Fracture Constraint on Failure Diagram

2011 ◽  
Vol 11 (11) ◽  
pp. 2006-2011 ◽  
Author(s):  
J.B. Ariatedja ◽  
O. Mamat
1962 ◽  
Vol 29 (4) ◽  
pp. 651-654 ◽  
Author(s):  
G. R. Irwin

The crack stress-field parameter K and crack-extension force G at boundary points of a flat elliptical crack may be derived from knowledge that normal tension produces an ellipsoidal crack opening. Rough correction procedures can be employed to adapt this result for application to a part-through crack in a plate subjected to tension. Experimental measurements suggest this adapted result has a useful range of accuracy.


2011 ◽  
Vol 25 (5) ◽  
pp. 1674-1686 ◽  
Author(s):  
L. Rubio ◽  
B. Muñoz-Abella ◽  
G. Loaiza

2018 ◽  
Vol 24 (6) ◽  
pp. 1821-1848 ◽  
Author(s):  
Yuan Li ◽  
CuiYing Fan ◽  
Qing-Hua Qin ◽  
MingHao Zhao

An elliptical crack subjected to coupled phonon–phason loadings in a three-dimensional body of two-dimensional hexagonal quasicrystals is analytically investigated. Owing to the existence of the crack, the phonon and phason displacements are discontinuous along the crack face. The phonon and phason displacement discontinuities serve as the unknown variables in the generalized potential function method which are used to derive the boundary integral equations. These boundary integral equations governing Mode I, II, and III crack problems in two-dimensional hexagonal quasicrystals are expressed in integral differential form and hypersingular integral form, respectively. Closed-form exact solutions to the elliptical crack problems are first derived for two-dimensional hexagonal quasicrystals. The corresponding fracture parameters, including displacement discontinuities along the crack face and stress intensity factors, are presented considering all three crack cases of Modes I, II, and III. Analytical solutions for a penny-shaped crack, as a special case of the elliptical problem, are given. The obtained analytical solutions are graphically presented and numerically verified by the extended displacement discontinuities boundary element method.


2000 ◽  
Author(s):  
Z. C. Xia

Abstract A mathematical analysis of failure developments for tubular hydroforming under combined internal pressure and end feeding is presented in this paper. Under considerations are two distinct failure modes, namely the bursting and the wrinkling. Bursting is an instability phenomenon where the tube can’t sustain any more tensile loading. Splitting usually follows due to extreme deformations in the bursting area. Wrinkling is due to high compression load, which deteriates the qulity of the final product. The deformation theory of plasticity is utilized in this study that takes into account of material anisotropy. The governing equations for the onset of both failure modes are established. The results are presented as Hydroforming Failure Diagram in the End Feed – Internal Pressure space. A parametric study of the failure criteria for a variety of materials and process parameters is performed. It is shown that the material anisotropy plays a significant role. The results provide guidelines for product designers and process engineers for the avoidance of failure during hydroforming. The validity and applicability of current study are also discussed.


Sign in / Sign up

Export Citation Format

Share Document