Session: MF-01-01 Application of Fracture Mechanics in Failure Assessment I

Paper Number: 61684

Start Time: Wednesday, July 14, 2021, 09:00 AM

61684 - Stress Intensity Factor Predictions at Clad Interfaces 

When a crack crosses a clad to plate interface, there is a further requirement to assess the material interface location, in terms of fatigue crack growth behaviour and crack extension by ductile tearing, beyond the typically considered surface and deepest point locations. However, typical solutions for elastic stress intensity factor (K_I), such as those in R6, only consider the surface and deepest point locations and do not account for any interactions at such material interfaces. Subsequently, the assessment may look to describe the interface region by the maximum of the surface or deepest point values or it may be argued to be the value from either the surface or deepest point, depending on which is geometrically closer. This has the potential to lead to overly conservative interpretations in terms of K_I and K_J, as well as the fracture toughness and growth laws used.

The work presented here investigates the influence of the clad to plate interface on stress intensity factor under elastic (K_I) and elastic-plastic (K_J) conditions for a number of defect geometries, loading conditions and material properties. The results seek to provide guidance on the suitability of K_I and K_J solutions for the surface and deepest points, to describe the interface region when a crack crosses a clad boundary.

Presenting Author: William Brayshaw Jacobs

Authors:

William Brayshaw Jacobs
Peter James Jacobs
Ben Pellereau Rolls-Royce