Institute of Physics of Materials AS CR, v. v. i. > Projects > Description of short fatigue crack growth in large scale yielding conditions
Description of short fatigue crack growth in large scale yielding conditions
Investigator | prof. Mgr. Tomáš Kruml, CSc. |
Number of Project | 18-03615S |
Agency | Grantová agentura České republiky |
Duration | 2018-01-01 - 2020-12-31 |
Anotace |
The prediction of residual fatigue life of structures or components with cracks requires knowledge about the crack growth rate. Theory and experimental procedures for the measurement of the crack growth rate in the small scale yielding conditions at the crack tip is well established. However, the kinetics of crack growth rate in condition of a non-negligible plasticity around the crack tip has been studied to much lesser extent. Recently, a large set of short fatigue crack growth rate data measured in the applicant’s laboratory were reanalysed. This comparison revealed that the plastic part of the J-integral (and not the total J-integral) is the parameter governing the short crack growth rate in large scale yielding conditions. Moreover, crack growth rate data from all analysed materials lie on a unique curve. This remarkable observation suggests that the crack growth rate is determined by the extent of energy spent to plastic deformation at the crack tip, irrespective of the other materials properties. In this project, we want to critically assess this hypothesis. |