Home > Search Results: keywords:"short fatigue cracks"
Search:
Search Tips :: Advanced Search
Search collections:
Sort by: Display results: Output format:
National Repository of Grey Literature 3 records found  Search took 0.00 seconds. 
Two-Parameter Approach for Short Cracks at Notches
 Seitl, Stanislav ; Hutař, Pavel ; Knésl, Zdeněk
A two parameter constraint-based fracture mechanics method is applied to the behavior of microstructurally and mechanically short fatigue cracks. A short crack in the vicinity of a grain boundary and a crack which is engulfed by the plastic strain field of a notch are studied as examples. The different levels of stress constraint are quantified by using the T-stress and the Q parameter. The corresponding calculations are performed by using a finite element method (ANSYS system). The influence of the T values on the propagation of short fatigue cracks is analyzed. The size of the plastic zone and the crack closure are significantly affected by the level of constraint. The influence of constraint on small fatigue crack growth kinetic is studied under the assumption that the controlling variable for the rate of propagation of the fatigue crack is the size of the plastic zone.
Detailed record
Quantitative Assessment of the T-stress in Short Fatigue Crack Propagation
 Seitl, Stanislav ; Knésl, Zdeněk
Two parameter constrained based fracture mechanics is applied to quantitative assessment of microstructurally short fatigue cracks propagation. The different levels of a stress constraint are quantified by T-stress. Corresponding calculations are performed by finite element method (ANSYS system). The values of the T-stress are numerically estimated as a function of material properties, location and orientation of the short crack with respect to the grain boundary. The influence of constraint on small fatigue crack growth kinetic is discussed. It is shown that the level of constraint of the near-tip fields for microstructurally short fatigue cracks may influence the fatigue crack rate substantially.
Detailed record
Evalution of Q-parameter in the case of microstructurally short fatigue cracks
 Seitl, Stanislav
The paper presents evaluation of the elastic-plastic Q-parameter in the case of microstructurally short fatigue cracks, i.e. for cracks for which the crack size is comparable to the scale of the characteristic microstructural dimension such as the grain size. The microstructurally short crack is modelled as a crack with its tip in the vicinity of an interface between two different materials (elastic one and steel 12060), see Fig.1. Q-parameter is calculated by means of direct use of finite element results, namely the difference from the T = 0 reference solution, see Eq.5. Q-parameter is determined as a function of the crack orientation with respect to the interface, the crack length and the ratio of Young's modulus of both materials, see. Fig.1.
Detailed record

Interested in being notified about new results for this query?
Subscribe to the RSS feed.
Digital Repository :: Search :: Submit :: Personalize :: Help
Powered by Invenio v1.1.2
Maintained by admin.invenio@techlib.cz
This site is also available in the following languages:
Česky  English